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Quatermass II is a British science-fiction serial, originally broadcast by BBC Television in 1955. It is the second in the Quatermass series by writer Nigel Kneale, and the first of those serials to survive in its entirety in the BBC archives. It is also the earliest surviving complete British science-fiction television
production. The serial sees Professor Bernard Quatermass of the British
Experimental Rocket Group being asked to examine strange meteorite showers. His investigations lead to his uncovering a conspiracy involving alien infiltration at the highest levels of the British Government. As some of Quatermass's closest colleagues fall victim to the alien influence, he is forced to use his own unsafe rocket prototype, which recently caused a nuclear disaster at an Australian testing range, to prevent the aliens from taking over mankind. Although sometimes compared unfavourably to the first and third Quatermass serials, Quatermass II was praised for its allegorical concerns of the damaging effects of
industrialisation and the corruption of governments by big business. It is
described on the British Film Institute's "Screenonline" website as "compulsive viewing." (Full article...)
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Mona Lisa (La Joconde) is a half-length portrait of a woman by Leonardo da Vinci which was probably completed between 1503 and 1506, with further refinement continuing until 1517. Though the painting is thought to be of
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Bioelectromagnetics
Bioelectromagnetics, also known as bioelectromagnetism, is the study of the interaction between electromagnetic fields and biological entities. Areas of study include electrical or electromagnetic fields produced by living cells, tissues or
organisms; for example, the cell membrane potential and the electric currents that flow in nerves and muscles, as a result of action potentials. Others include
animal navigation utilizing the geomagnetic field; potential effects of man-made sources of electromagnetic fields like mobile phones; and developing new
therapies to treat various conditions. The term can also refer to the ability of living cells, tissues, and organisms to produce electrical fields and the response of cells to electromagnetic fields.
Biological phenomena
Short-lived electrical events called action potentials occur in several types of animal cells which are called excitable cells, a category of cell include neurons, muscle cells, and endocrine cells, as well as in some plant cells. These action potentials are used to facilitate inter-cellular communication and activate intracellular processes. The physiological phenomena of action potentials are possible because voltage-gated ion channels allow the resting potential caused by electrochemical gradient on either side of a cell membrane to resolve.
Bioelectromagnetism is studied primarily through the techniques of
electrophysiology. In the late eighteenth century, the Italian physician and
physicist Luigi Galvani first recorded the phenomenon while dissecting a frog at a table where he had been conducting experiments with static electricity.
Galvani coined the term animal electricity to describe the phenomenon, while contemporaries labeled it galvanism. Galvani and contemporaries regarded muscle activation as resulting from an electrical fluid or substance in the nerves. Some usually aquatic animals have acute bioelectric sensors providing a sense known as electroreception while migratory birds navigate in part by orienteering with respect to the Earth's magnetic field. In an extreme application of
electromagnetism the electric eel is able to generate a large electric field outside its body used for hunting and self defense through a dedicated electric organ.
Thermal effects
Most of the molecules in the human body interact weakly with electromagnetic fields in the radiofrequency or extremely low frequency bands.[citation needed] One
such interaction is absorption of energy from the fields, which can cause tissue to heat up; more intense fields will produce greater heating. This can lead to biological effects ranging from muscle relaxation (as produced by a diathermy
device) to burns.Many nations and regulatory bodies like the International Commission on Non-Ionizing Radiation Protection have established safety guidelines to limit EMF exposure to a non-thermal level. This can be defined as either heating only to the point where the excess heat can be dissipated, or as a fixed increase in temperature not detectable with current instruments like 0.1°C.
[citation needed] However, biological effects have been shown to be present for these
non-thermal exposures;[citation needed] Various mechanisms have been proposed to
explain these,1 and there may be several mechanisms underlying the differing
phenomena observed. Biological effects of weak electromagnetic fields are the subject of study in magnetobiology.[citation needed]
Behavioral effects
Many behavioral effects at different intensities have been reported from exposure to magnetic fields, particularly with pulsed magnetic fields. The specific pulseform used appears to be an important factor for the behavioural effect seen; for example, a pulsed magnetic field originally designed for
spectroscopic MRI was found to alleviate symptoms in bipolar patients, while another MRI pulse had no effect. A whole-body exposure to a pulsed magnetic field was found to alter standing balance and pain perception in other studies.
TMS and related effects
A strong changing magnetic field can induce electrical currents in conductive tissue such as the brain. Since the magnetic field penetrates tissue, it can be generated outside of the head to induce currents within, causing transcranial magnetic stimulation (TMS). These currents depolarize neurons in a selected part of the brain, leading to changes in the patterns of neural activity. In repeated pulse TMS therapy or rTMS, the presence of incompatible EEG electrodes can result in electrode heating and, in severe cases, skin burns. A number of scientists and clinicians are attempting to use TMS to replace
electroconvulsive therapy (ECT) to treat disorders such as severe depression. Instead of one strong electric shock through the head as in ECT, a large number of relatively weak pulses are delivered in TMS therapy, typically at the rate of about 10 pulses per second. If very strong pulses at a rapid rate are delivered to the brain, the induced currents can cause convulsions much like in the original
electroconvulsive therapy. Sometimes, this is done deliberately in order to treat depression, such as in ECT.
Health effects of artificial electromagnetic fields
and current use in medical therapy
While health effects from extremely low frequency (ELF) electric and magnetic fields (0 to 300 Hz) generated by power lines, and radio/microwave frequencies (RF) (10 MHz - 300 GHz) emitted by radio antennas and wireless networks have been well studied, the intermediate range (IR) used increasingly in modern telecommunications (300 Hz to 10 MHz) has been studied far less. Direct effects of electromagnetism on human health have been difficult to prove, and
documented life threatening interferences from electromagnetic fields are limited to medical devices such as pacemakers and other electronic implants.2
However, a number of studies have been conducted with artificial magnetic fields
and electric fields to investigate for example their effects on cell metabolism,
apoptosis and tumor growth.3 Electromagnetic radiation in the intermediate
frequency range has found a place in modern medical practice for the treatment of bone healing and for nerve stimulation and regeneration; it is now also
approved as a novel cancer therapy in form of Tumor Treating Fields, which are alternating electric fields in the frequency range of 100–300 kHz. Since some of these methods involve magnetic fields that invoke electric currents in biological tissues and others only involve electric fields, they are strictly speaking
electrotherapies albeit their application modi with modern electronic equipment have placed them in the category of bioelectromagnetic interactions.
2Electromagnetic fields & public health: Intermediate Frequencies (IF). Information sheet February 2005. World Health Organization. Retrieved Aug 2013.
3Wartenberg, M., Wirtz, N., Grob, A., Niedermeier, W., Hescheler, J., Peters, S. C. and Sauer, H. (2008), "Direct current electrical fields induce apoptosis in oral mucosa cancer cells by NADPH oxidase-derived reactive oxygen species". Bioelectromagnetics, 29: 47–54. doi:
References
Organizations
•The Bioelectromagnetics Society (BEMS)
•European BioElectomagnetics Association (EBEA)
•Society for Physical Regulation in Biology and Medicine (SPRBM) (formerly the Bioelectrical Repair and Growth Society, BRAGS)
•International Society for Bioelectromagnetism (ISBEM)
•The Bioelectromagnetics Lab at University College Cork, Ireland
•Institute of Bioelectromagnetism
•Vanderbilt University, Living State Physics Group, archived page
•Ragnar Granit Institute.
•Institute of Photonics and Electronics AS CR, Department of Bioelectrodynamics.
Books
•Becker, Robert O.; Andrew A. Marino, Electromagnetism and Life, State University of New York Press, Albany, 1982. ISBN 0-87395-561-7.
•Becker, Robert O.; The Body Electric: Electromagnetism and the Foundation of Life, William Morrow & Co, 1985. ISBN 0-688-00123-8.
•Becker, Robert O.; Cross Currents: The Promise of Electromedicine, the Perils of Electropollution, Tarcher, 1989. ISBN 0-87477-536-1.
•Binhi, V.N., Magnetobiology: Underlying Physical Problems. San Diego: Academic Press, 2002. ISBN 0-12-100071-0.
•Brodeur Paul; Currents of Death, Simon & Schuster, 2000. ISBN 0-7432-1308-4. •Carpenter, David O.; Sinerik Ayrapetyan, Biological Effects of Electric and Magnetic Fields, Volume 1 : Sources and Mechanisms, Academic Press, 1994. ISBN 0-12-160261-3.
•Carpenter, David O.; Sinerik Ayrapetyan, Biological Effects of Electric and Magnetic Fields : Beneficial and Harmful Effects (Vol 2), Academic Press, 1994. ISBN 0-12-160261-3.
•Chiabrera A. (Editor), Interactions Between Electromagnetic Fields and Cells, Springer, 1985. ISBN 0-306-42083-X.
•Habash, Riadh W. Y.; Electromagnetic Fields and Radiation: Human Bioeffects and Safety, Marcel Dekker, 2001. ISBN 0-8247-0677-3.
•Horton William F.; Saul Goldberg, Power Frequency Magnetic Fields and Public Health, CRC Press, 1995. ISBN 0-8493-9420-1.
•Mae-Wan, Ho; et al., Bioelectrodynamics and Biocommunication, World Scientific, 1994. ISBN 981-02-1665-3.
•Malmivuo, Jaakko; Robert Plonsey, Bioelectromagnetism: Principles and Applications of Bioelectric and Biomagnetic Fields, Oxford University Press, 1995. ISBN 0-19-505823-2.
•O'Connor, Mary E. (Editor), et al., Emerging Electromagnetic Medicine, Springer, 1990. ISBN 0-387-97224-2.
Journals
•Bioelectromagnetics, Wiley, 1985–present, (ISSN 0197-8462) •Bioelectrochemistry, Elsevier, 1974–present, (ISSN 1567-5394)
•International Journal of Bioelectromagnetism, ISBEM, 1999–present, (ISSN 1456-7865)
•BioMagnetic Research and Technology archive (no longer publishing) •Biophysics, English version of the Russian "Biofizika" (ISSN 0006-3509)
•Radiatsionnaya Bioliogiya Radioecologia ("Radiation Biology and Radioecology", in Russian) (ISSN:0869-8031)
External links
•A brief history of Bioelectromagnetism, by Jaakko and Plonsey. •Direct and Inverse Bioelectric Field Problems
•Human body meshes for MATLAB, Ansoft/ANSYS HFSS, Octave (surface meshes from real subjects, meshes for Visible Human Project)
Magnetobiology
Magnetobiology is the study of biological effects of mainly weak static and low-frequency magnetic fields, which do not cause heating of tissues.
Magnetobiological effects have unique features that obviously distinguish them from thermal effects; often they are observed for alternating magnetic fields just in separate frequency and amplitude intervals. Also, they are dependent of
simultaneously present static magnetic or electric fields and their polarization. Magnetobiology is a subset of bioelectromagnetics. Bioelectromagnetism and
biomagnetism are the study of the production of electromagnetic and magnetic fields by biological organisms. The sensing of magnetic fields by organisms is known as magnetoreception.
Biological effects of weak low frequency magnetic fields, less than about 0.1
millitesla (or 1 Gauss) and 100 Hz correspondingly, constitutes a physics problem. The effects look paradoxical, for the energy quantum of these
electromagnetic fields is by many orders of value less than the energy scale of an elementary chemical act. On the other hand, the field intensity is not enough to cause any appreciable heating of biological tissues or irritate nerves by the induced electric currents.
An example of magnetobiological effects is the magnetic navigation by migrant animals. It is established that some animals are able to detect small variations of the geomagnetic field on the order of tens of nanoteslas to find their seasonal habitats.
Reproducibility
The results of magnetobiological experiments are poorly reproducible. 10–20% of publications report failed attempts to observe magnetobiological effects. In the majority of experiments, success depended on a rare happy coincidence of suitable electromagnetic and physiological conditions. Many of the experiments await confirmation by independent studies.
Safety standards
Practical significance of magnetobiology is conditioned by the growing level of the background electromagnetic exposure of people. Some electromagnetic fields at chronic exposures may pose a threat to human health. World Health Organization considers enhanced level of electromagnetic exposure at working places as a stress factor. Present electromagnetic safety standards, worked out by many national and international institutions, differ by tens and hundreds of times for certain EMF ranges; this situation reflects the lack of research in the area of magnetobiology and electromagnetobiology. Today, the most of the standards take into account biological effects just from heating by
electromagnetic fields, and peripheral nerve stimulation from induced currents.
Medical approach
Practitioners of magnet therapy attempt to treat pain or other medical conditions by relatively weak electromagnetic fields. These methods have not yet received clinical evidence in accordance with accepted standards of evidence-based medicine. Some institutions recognize the practice as a pseudoscientific one. Other institutions, such as NASA, use magnet technology for biological
Possible causes of the effects
In magnetobiology, theory is lagging far behind experiment. The nature of
biological effects of weak electromagnetic fields remains unclear as yet, despite numerous experimental data. The following suggested causes of
magnetobiological phenomena are frequently discussed:
1. Crystallization of iron-bearing magnetic nanoparticles in tissues of the organism,
2. Dependence of some biochemical free-radical reactions on the magnetic field magnitude,
3. Possible existence of long-lived rotational states of some molecules inside
protein structures,
4. Magnetically induced changes in physical/chemical properties of liquid
water.
Explanation of the physical nature of biological effects of weak magnetic fields is a fundamental scientific problem.
Profile scientific journals
•Bioelectromagnetics
•Electromagnetic Biology and Medicine
•Biomedical Radioelectronics
•Biophysics
Further reading
•Presman A.S. Electromagnetic Fields and Life, Plenum, New York, 1970.
•Kirschvink J.L., Jones D.S., MacFadden B.J. (Eds.) Magnetite Biomineralization and Magnetoreception in Organisms. A New Biomagnetism, Plenum, New York, 1985.
•Binhi V.N. Magnetobiology: Underlying Physical Problems. — Academic Press, San Diego, 2002. — 473 p. — ISBN 0-12-100071-0
•Binhi V.N., Savin A.V. Effects of weak magnetic fields on biological systems: Physical aspects. Physics – Uspekhi, V.46(3), Pp.259–291, 2003.
Biophysics
Biophysics is an interdisciplinary science using methods of, and theories from,
physics to study biological systems.4 Biophysics spans all levels of biological
organization, from the molecular scale to whole organisms and ecosystems. Biophysical research shares significant overlap with biochemistry,
nanotechnology, bioengineering, agrophysics, and systems biology. It has been suggested as a bridge between biology and physics.
Overview
Molecular biophysics typically addresses biological questions similar to those in
biochemistry and molecular biology, but more quantitatively. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA, RNA and protein biosynthesis, as well as how these interactions are regulated. A great variety of techniques is used to answer these questions.
Fluorescent imaging techniques, as well as electron microscopy, x-ray
crystallography, NMR spectroscopy and atomic force microscopy (AFM) are often used to visualize structures of biological significance. Conformational change in structure can be measured using techniques such as dual polarisation interferometry and circular dichroism. Direct manipulation of molecules using
optical tweezers or AFM can also be used to monitor biological events where forces and distances are at the nanoscale. Molecular biophysicists often consider complex biological events as systems of interacting units which can be
understood through statistical mechanics, thermodynamics and chemical
kinetics. By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are often able to directly observe, model or even manipulate the structures and interactions of individual molecules or complexes of molecules.
In addition to traditional (i.e. molecular and cellular) biophysical topics like
structural biology or enzyme kinetics, modern biophysics encompasses an
extraordinarily broad range of research, from bioelectronics to quantum biology
involving both experimental and theoretical tools. It is becoming increasingly common for biophysicists to apply the models and experimental techniques derived from physics, as well as mathematics and statistics (see
biomathematics), to larger systems such as tissues, organs (e.g. see
cardiophysics), populations and ecosystems. Biophysics is now used extensively in the study of electrical conduction in single neurons, as well as neural circuit analysis in both tissue and whole brain.
Focus as a subfield
Generally, biophysics does not have university-level departments of its own, but has presence as groups across departments within the fields of molecular
biology, biochemistry, chemistry, computer science, mathematics, medicine,
pharmacology, physiology, physics, and neuroscience. What follows is a list of examples of how each department applies its efforts toward the study of
biophysics. This list is hardly all inclusive. Nor does each subject of study belong exclusively to any particular department. Each academic institution makes its own rules and there is much overlap between departments.
•Biology and molecular biology - Almost all forms of biophysics efforts are included in some biology department somewhere. To include some: gene regulation, single protein dynamics, bioenergetics, patch clamping,
biomechanics.
•Structural biology - Ångstrom-resolution structures of proteins, nucleic acids, lipids, carbohydrates, and complexes thereof.
•Biochemistry and chemistry - biomolecular structure, siRNA, nucleic acid structure, structure-activity relationships.
•Computer science - Neural networks, biomolecular and drug databases.
•Computational chemistry - molecular dynamics simulation, molecular docking,
quantum chemistry
•Bioinformatics - sequence alignment, structural alignment, protein structure prediction
•Mathematics - graph/network theory, population modeling, dynamical systems,
phylogenetics.
•Medicine and neuroscience - tackling neural networks experimentally (brain slicing) as well as theoretically (computer models), membrane permitivity, gene therapy, understanding tumors.
•Pharmacology and physiology - channelomics, biomolecular interactions, cellular membranes, polyketides.
•Physics - negentropy, stochastic processes, covering dynamics.
•Quantum biophysics involves quantum information processing of coherent states, entanglement between coherent protons and transcriptase components, and replication of decohered isomers to yield time-dependent base substitutions. These studies imply applications in quantum computing.
•Agronomy and agriculture
Many biophysical techniques are unique to this field. Research efforts in biophysics are often initiated by scientists who were traditional physicists, chemists, and biologists by training.
Notes
•Perutz MF (1962). Proteins and Nucleic Acids: Structure and Function. Amsterdam: Elsevier. ASIN B000TS8P4G.
•Perutz MF (1969). "The haemoglobin molecule". Proceedings of the Royal Society of London. Series B 173 (31): 113–40. Bibcode: 1969RSPSB.173..113P.
doi: 10.1098/rspb.1969.0043. PMID 4389425.
•Dogonadze RR, Urushadze ZD (1971). "Semi-Classical Method of Calculation of Rates of Chemical Reactions Proceeding in Polar Liquids". J Electroanal Chem 32 (2): 235–245. doi: 10.1016/S0022-0728(71)80189-4.
•Volkenshtein M.V., Dogonadze R.R., Madumarov A.K., Urushadze Z.D. and Kharkats Yu.I. Theory of Enzyme Catalysis.- Molekuliarnaya Biologia (Moscow), 6, 1972, pp. 431–439 (In Russian, English summary. Available translations in Italian, Spanish, English, French)
•Rodney M. J. Cotterill (2002). Biophysics : An Introduction. Wiley. ISBN 978-0-471-48538-4.
•Sneppen K, Zocchi G (2005-10-17). Physics in Molecular Biology (1 ed.).
Cambridge University Press. ISBN 0-521-84419-3.
•Glaser, Roland (2004-11-23). Biophysics: An Introduction (Corrected ed.). Springer. ISBN 3-540-67088-2.
•Hobbie RK, Roth BJ (2006). Intermediate Physics for Medicine and Biology (4th ed.). Springer. ISBN 978-0-387-30942-2.
•Cooper WG (2009). "Evidence for transcriptase quantum processing implies entanglement and decoherence of superposition proton states". BioSystems 97 (2): 73–89. doi: 10.1016/j.biosystems.2009.04.010. PMID 19427355.
•Cooper WG (2009). "Necessity of quantum coherence to account for the
spectrum of time-dependent mutations exhibited by bacteriophage T4". Biochem. Genet. 47 (11–12): 892–910. doi: 10.1007/s10528-009-9293-8. PMID 19882244. •Goldfarb, Daniel (2010). Biophysics Demystified. McGraw-Hill. ISBN 0-07-163365-0.
External links
•Biophysical Society
•Journal of Physiology: 2012 virtual issue Biophysics and Beyond
•bio-physics-wiki
•Link archive of learning resources for students: biophysika.de (60% English, 40% German)
Electrical brain stimulation
Electrical brain stimulation (EBS), also referred to as focal brain
stimulation (FBS), is a form of electrotherapy and technique used in research
and clinical neurobiology to stimulate a neuron or neural network in the brain
through the direct or indirect excitation of its cell membrane by using an electric current. It is used for research or for therapeutical purposes.
History
Electrical brain stimulation was first used in the first half of the 19th century by pioneering researchers such as Luigi Rolando [citation needed](1773–1831) and Pierre
Flourens [citation needed](1794–1867), to study the brain localization of function,
following the discovery by Italian physician Luigi Galvani (1737–1798) that
nerves and muscles were electrically excitable. The stimulation of the surface of the cerebral cortex by using brain stimulation was used to investigate the motor cortex in animals by researchers such as Eduard Hitzig (1838–1907), Gustav Fritsch (1838–1927), David Ferrier (1842–1928) and Friedrich Goltz (1834– 1902). The human cortex was also stimulated electrically by neurosurgeons and
neurologists such as Robert Bartholow (1831–1904) and Fedor Krause (1857– 1937).
In the following century, the technique was improved by the invention of the
stereotactic method by British neurosurgeon pioneer Victor Horsley (1857– 1916), and by the development of chronic electrode implants by Swiss
neurophysiologist Walter Rudolf Hess (1881–1973), José Delgado (1915-2011) and others, by using electrodes manufactured by straight insulated wire that could be inserted deep into the brain of freely-behaving animals, such as cats and monkeys. This approach was used by James Olds (1922–1976) and
colleagues to discover brain stimulation reward and the pleasure center.
American-Canadian neurosurgeon Wilder Penfield (1891–1976) and colleagues at the Montreal Neurological Institute used extensively electrical stimulation of the brain cortex in awake neurosurgical patients to investigate the motor and
sensory homunculus (the representation of the body in the brain cortex according to the distribution of motor and sensory territories).
Process
Two-photon excitation microscopy has shown that microstimulation activates neurons sparsely around the electrode even at low currents (as low as 10 μA) up to distances as far as four millimeters away. This happens without particularly selecting other neurons much nearer the electrode's tip. This is due to activation of neurons being determined by whether they do or do not have axons or
dendrites that pass within a radius of 15 μm near the tip of the electrode. As the current is increased the volume around the tip that activates neuron axons and dendrites increases and with this the number of neurons activated. Activation is most likely to be due to direct depolarization rather than synaptic activation.
Therapeutic applications
Examples of therapeutic EBS are:
•Cranial electrotherapy stimulation (CES) •Deep brain stimulation (DBS)
•Transcranial direct current stimulation (tDCS) •Electroconvulsive therapy (ECT)
•Functional electrical stimulation (FES) •Magnetic seizure therapy (MST)
•Vagus nerve stimulation (VNS)
Strong electric currents may cause a localized lesion in the nervous tissue, instead of a functional reversible stimulation. This property has been used for neurosurgical procedures in a variety of treatments, such as for Parkinson's disease, focal epilepsy and psychosurgery. Sometimes the same electrode is used to probe the brain for finding defective functions, before passing the lesioning current (electrocoagulation).
Electroconvulsive therapy
Electroconvulsive therapy Intervention ICD-10-PCS GZB ICD-9-CM 94.27 MeSH D004565 OPS-301 code: 8-630 MedlinePlus 007474Electroconvulsive therapy (ECT), formerly known as electroshock, is a standard psychiatric treatment in which seizures are electrically induced in anesthetized patients for symptom remission. Its mode of action is unknown. The use of electroconvulsive therapy evolved out of convulsive therapy. Long before electric shocks were being administered to induce seizures, doctors were using other drugs and methods to induce seizures as a means of treatment for severe
depression and schizophrenia. Today, ECT is used as a treatment for clinical depression that has not responded to other treatment, and sometimes for mania
and catatonia. It was first introduced in 1938 by Italian neuropsychiatrists Ugo Cerletti and Lucio Bini, and gained widespread popularity as a form of treatment in the 1940s and 1950s.5
In popular culture, it is usually depicted as a painful procedure, but in western countries ECT is usually administered under anesthetic with a muscle relaxant.6
Electroconvulsive therapy can differ in its application in three ways: electrode placement, frequency of treatments, and the electrical waveform of the stimulus. These three forms of application have significant differences in both adverse side effects and symptom remission. After treatment, drug therapy is usually
continued, and some patients receive maintenance ECT. In the United Kingdom and Ireland, drug therapy usually is continued during ECT.
About 70 percent of ECT patients are women, since they are at twice the risk of depression than are men.7 Although a large amount of research has been carried
out, the exact mechanism of action of ECT remains elusive, and ECT on its own does not usually have a sustained benefit. There is usually a risk of memory loss
with ECT. It is deemed by the World Health Organization, that obtaining the written, informed consent of the patient is necessary before ECT is
administered.8 In the United Kingdom, around a third of patients who are
receiving ECT haven't consented to it. They are deemed by the legal system as being too mentally ill to provide consent and ECT is still provided since the legal system feels it's in their best self-interest.9 Likewise is the case when ECT is
often administered on adolescents.10 Psychiatrists and other mental health
professionals differ on when and if ECT should be used as a first-line treatment or if it should be reserved for patients who have not responded to other
interventions such as medication and psychotherapy. ECT is considered one of the least harmful treatment options available for severely depressed pregnant women.11
5Psychology Frontiers and Applications – Second Canadian Edition (Passer, Smith, Atkinson, Mitchell, Muir)
6http://psychcentral.com/lib/5-outdated-beliefs-about-ect/00011255
7http://umm.edu/health/medical/reports/articles/depression
8World Health Organisation (2005). WHO Resource Book on Mental Health, Human Rights and Legislation. Geneva, 64.
9http://www.bbc.co.uk/news/health-23414888
10http://www.annals-general-psychiatry.com/content/12/1/17
History
As early as the 16th century, agents to induce seizures were used to treat psychiatric conditions. In 1785, the therapeutic use of seizure induction was documented in the London Medical Journal. Convulsive therapy was introduced in 1934 by Hungarian neuropsychiatrist Ladislas J. Meduna who, believing
mistakenly that schizophrenia and epilepsy were antagonistic disorders, induced seizures first with camphor and then metrazol (cardiazol). Ladislas Meduna is thought to be the father of convulsive therapy. In 1937, the first international meeting on convulsive therapy was held in Switzerland by the Swiss psychiatrist Muller. The proceedings were published in the American Journal of Psychiatry and, within three years, cardiazol convulsive therapy was being used worldwide. Italian Professor of neuropsychiatry Ugo Cerletti, who had been using electric shocks to produce seizures in animal experiments, and his colleague Lucio Bini
developed the idea of using electricity as a substitute for metrazol in convulsive therapy and, in 1937, experimented for the first time on a person. It was known early on that inducing convulsions aided in helping those with severe
schizophrenia. Cerletti had noted a shock to the head produced convulsions in dogs. The idea to use electroshock on humans came to Cerletti when he saw how pigs were given an electric shock before being butchered to put them in an anesthetized state. Cerletti and Bini practiced until they felt they had the right parameters needed to have a successful human trial. Once they started trials on patients they found that after 10-20 treatments the results were significant. Patients had much improved. A positive side effect to the treatment was retrograde amnesia. It was because of this side effect that patients could not remember the treatments and had no ill feelings toward it. ECT soon replaced metrazol therapy all over the world because it was cheaper, less frightening and more convenient.12 Cerletti and Bini were nominated for a Nobel Prize but did
not receive one. By 1940, the procedure was introduced to both England and the US. In Germany and Austria it was promoted by Friedrich Meggendorfer.
Through the 1940s and 1950s, the use of ECT became widespread.
12Cerletti, U (1956). "Electroshock therapy". In AM Sackler et al. (eds) The Great Physiodynamic
In the early 1940s, in an attempt to reduce the memory disturbance and
confusion associated with treatment, two modifications were introduced: the use of unilateral electrode placement and the replacement of sinusoidal current with brief pulse. It took many years for brief-pulse equipment to be widely adopted.13
In the 1940s and early 1950s ECT was usually given in "unmodified" form, without muscle relaxants, and the seizure resulted in a full-scale convulsion. A rare but serious complication of unmodified ECT was fracture or dislocation of the long bones. In the 1940s psychiatrists began to experiment with curare, the muscle-paralysing South American poison, in order to modify the convulsions. The introduction of suxamethonium (succinylcholine), a safer synthetic
alternative to curare, in 1951 led to the more widespread use of "modified" ECT. A short-acting anesthetic was usually given in addition to the muscle relaxant in order to spare patients the terrifying feeling of suffocation that can be
experienced with muscle relaxants.
The steady growth of antidepressant use along with negative depictions of ECT in the mass media led to a marked decline in the use of ECT during the 1950s to the 1970s. The Surgeon General stated there were problems with electroshock therapy in the initial years before anesthesia was routinely given, and that "these now-antiquated practices contributed to the negative portrayal of ECT in the popular media." The New York Times described the public's negative perception of ECT as being caused mainly by one movie. "For Big Nurse in One Flew Over the Cuckoo's Nest, it was a tool of terror, and, in the public mind, shock therapy has retained the tarnished image given it by Ken Kesey's novel: dangerous, inhumane and overused".
In 1976, Dr. Blatchley demonstrated the effectiveness of his constant current, brief pulse device ECT. This device eventually largely replaced earlier devices because of the reduction in cognitive side effects, although as of 2012 some ECT clinics still were using sine-wave devices.14 The 1970s saw the publication of the
first American Psychiatric Association (APA) task force report on
electroconvulsive therapy (to be followed by further reports in 1990 and 2001). The report endorsed the use of ECT in the treatment of depression. The decade also saw criticism of ECT.15 Specifically critics pointed to shortcomings such as
noted side effects, the procedure being used as a form of abuse, and uneven application of ECT. The use of ECT declined until the 1980s, "when use began to increase amid growing awareness of its benefits and cost-effectiveness for
treating severe depression". In 1985 the National Institute of Mental Health and
National Institutes of Health convened a consensus development conference on ECT and concluded that, while ECT was the most controversial treatment in psychiatry and had significant side-effects, it had been shown to be effective for a narrow range of severe psychiatric disorders.
13Kiloh, LG, Smith, JS, Johnson, GF (1988). Physical Treatments in Psychiatry. Melbourne: Blackwell Scientific Publications, 190–208. ISBN 0-86793-112-4
14Leiknes KA, et al (2012) Contemporary use and practice of electroconvulsive therapy worldwide. Brain Behav. 2(3):283-344
15See Friedberg, J (1977). "Shock treatment, brain damage, and memory loss: a neurological perspective". American Journal of Psychiatry 134:1010–1014; and Breggin, PR (1979)
Due to the backlash noted previously, national institutions reviewed past
practices and set new standards. In 1978, The American Psychiatric Association released its first task force report in which new standards for consent were introduced and the use of unilateral electrode placement was recommended. The 1985 NIMH Consensus Conference confirmed the therapeutic role of ECT in certain circumstances. The American Psychiatric Association released its second task force report in 1990 where specific details on the delivery, education, and training of ECT were documented. Finally in 2001 the American Psychiatric Association released its latest task force report. This report emphasizes the importance of informed consent, and the expanded role that the procedure has in modern medicine.
Mechanism of action
Despite decades of research, the exact mechanism of action of ECT remains elusive. Ladislas J. Meduna believed that chemically induced seizures, brought on by drugs, could change the chemical makeup of the brain of a patient with schizophrenia. Modern electroconvulsive therapy operates under a similar
hypothesis, though in modern practice a therapeutic clonic seizure is induced by electrical current via electrodes placed on an anesthetized, unconscious patient. It is known that the central nervous system is regulated by small electrical
current; disrupting or "restarting" that current by induced seizure (colloquially, "jumpstarting the brain"), has shown positive effects in patients with severe
depression or schizophrenia.
Peter Breggin, an outspoken and controversial critic of evidence-based psychiatry, claims that ECT induces "a closed-head injury caused by an
overwhelming current of electricity sufficient to cause a grand mal seizure" and that the improvements in mood seen in patients receiving ECT are resultant from brain damage.16 Such claims are rejected as wholly unsubstantiated by the
consensus of the scientific and medical community.
There is a vast body of literature on the effects of ECT in animals; however, though human and animal brains are very similar, animal models of depression
are widely acknowledged to parallel only limited aspects of depressive illness, a uniquely human disease. Some suggest pruning of normally dense synaptic
connections in the hippocampus, a richly connected area deep in the temporal lobe vital in controlling both mood and memory, seen in animal studies may play a role in its effectiveness.
16Dr. Peter Breggin for Huffington Post. February 9, 2008. Brain-Disabling Treatments in Psychiatry: Drugs, Electroshock and the Psychopharmaceutical Complex
Selection of patients for ECT
Experts disagree on whether ECT is an appropriate first-line treatment or if it should be reserved for patients who have not responded to other interventions such as medication and psychotherapy.
The American Psychiatric Association 2001 guidelines give the primary
indications for ECT among patients with depression as a lack of response to, or intolerance of, antidepressant medications; a good response to previous ECT; and the need for a rapid and definitive response (e.g. because of psychosis or a risk of suicide). The decision to use ECT depends on several factors, including the severity and chronicity of the depression, the likelihood that alternative treatments would be effective, the patient's preference and capacity to consent, and a weighing of the risks and benefits.17
Some guidelinesWikipedia:Avoid weasel words recommend cognitive behavioral therapy or other psychotherapy before ECT is used. However, treatment
resistance is widely defined as lack of therapeutic response to two
antidepressants at adequate doses for an adequate duration and with good
compliance. The APA states that at times patients will prefer to receive ECT over alternative treatments, but commonly the opposite will be the case.
The APA ECT guidelines state that severe major depression with psychotic features, manic delirium, or catatonia are conditions where there is a clear
consensus favoring early ECT. The UK's National Institute for Health and Clinical Excellence 2003 (NICE) guidelines recommended ECT for patients with severe depression, catatonia, or prolonged or severe mania. It did not recommend the use of ECT as a maintenance therapy in depressive illness as "the long-term benefits and risks ... had not been clearly established":5–6 and those
recommendations were unchanged in the 2010 update.:526 The 2001 APA
guidelines support the use of ECT for relapse prevention.
The 2001 APA ECT guidelines say that ECT is rarely used as a first-line treatment for schizophrenia, but is considered after unsuccessful treatment with
antipsychotic medication, and may also be considered in the treatment of
patients with schizoaffective or schizophreniform disorder. The 2003 NICE ECT guidelines do not recommend ECT for schizophrenia, and this has been
supported by meta-analytic evidence showing no or little benefit versus placebo, or in combination with antipsychotic drugs, including Clozapine.
The NICE 2003 guidelines state that doctors should be particularly cautious when considering ECT treatment for women who are pregnant and for older or younger people, because they may be at higher risk of complications with ECT. The 2001 APA ECT guidelines say that ECT may be safer than alternative
treatments in the infirm elderly and during pregnancy, and the 2000 APA depression guidelines stated that the literature supports the safety for mother and fetus, as well as the efficacy during pregnancy.
17Lisanby, S.H. (2007) Electroconvulsive Therapy for Depression Volume 357, No. 19, pp. 1939– 1945
ECT has been used in selected cases of depression occurring in the setting of
multiple sclerosis, Parkinson's disease, Huntington's chorea, developmental delay, brain arteriovenous malformations and hydrocephalus.
Efficacy
Non-clinical patient characteristics
About 70 percent of ECT patients are women. This is almost entirely due to women being at twice the risk of depression. Older and more affluent patients are also more likely to receive ECT. The use of ECT is not as common in ethnic minorities.
Degree of effectiveness and risks
Scientific papers and articles reviewing studies of ECT effectiveness have reached conflicting conclusions.
A meta-analysis done on the effectiveness of ECT in unipolar and bipolar
depression was conducted in 2012. Findings showed that although patients with unipolar depression and bipolar depression responded very differently to other medical treatments both groups responded equally as well to ECT. Overall remission rate for patients with unipolar depression was 51.5% and 50.9% in those with bipolar depression. The severity of each patient’s depression was assessed at the same baseline in each group.
In 2003, The UK ECT Review group published a systematic review and meta-analysis comparing ECT to placebo and antidepressant drugs. This meta-meta-analysis demonstrated a large effect size (high efficacy relative to the mean in terms of the standard deviation) for ECT versus placebo, and versus antidepressant drugs.
In 2006, a research article by Dr. Colin A. Ross found that no studies had ever shown that ECT was more effective than a placebo (sham ECT) treatment as of 1 month posttreatment.
In 2008, a meta-analytic review paper found in terms of efficacy, "a significant superiority of ECT in all comparisons: ECT versus simulated ECT, ECT versus placebo, ECT versus antidepressants in general, ECT versus TCAs and ECT versus MAOIs."
In 2010, a paper by Dr. John Reed and Dr. Richard Bentall found that ECT was only minimally more effective than a placebo during the treatment period, and that there was no difference in effect after the treatment period. In light of this finding, and the risk of side-effects, the authors concluded that the use of ECT "cannot be scientifically justified".
A 2011 paper in the Journal of Psychiatric Nurses Association reported that ECT was effective.18
Surveys of public opinion, the testimony of former patients, legal restrictions on its use and disputes as to the efficacy, ethics and adverse effects of ECT within the psychiatric and wider medical community indicate that the use of ECT remains controversial. This is reflected in the recent vote by the United States Food and Drug Administration's (FDA's) Neurological Devices Advisory Panel to recommend that FDA maintain ECT devices in the Class III device category for high risk devices except for patients suffering from catatonia. This may result in the manufacturers of such devices having to do controlled trials on their safety and efficacy for the first time.19 In justifying their position, panelists referred to
the memory loss associated with ECT and the lack of long-term data.
Duration of effect
ECT on its own does not usually have a sustained benefit. Half those who remit then relapse within six months. This is similar to the rate of relapse after
discontinuing antidepressant medication, and it has been suggested that it is due to the severity and chronicity of pre-existing illness for which ECT is generally used.20 The relapse rate in the first six months is reduced by the use of
psychiatric medications or further ECT, but remains high.
Probability of remission
The 1999 U.S. Surgeon General's Report on Mental Health summarized
psychiatric opinion at the time about the effectiveness of ECT. It stated that both clinical experience and published studies had determined ECT to be effective (with an average 60 to 70 percent remission rate) in the treatment of severe depression, some acute psychotic states, and mania. Its effectiveness had not been demonstrated in dysthymia, substance abuse, anxiety, or personality
disorder. The report stated that ECT does not have a long-term protective effect against suicide and should be regarded as a short-term treatment for an acute episode of illness, to be followed by continuation therapy in the form of drug treatment or further ECT at weekly to monthly intervals.21
18http://jap.sagepub.com/content/17/3/217.short
19Duff Wilson for the New York Times. January 28, 2011 F.D.A. Panel Is Split on Electroshock Risks
20Sackeim HA, Haskett RF, Mulsant BH, Thase ME, Mann JJ, Pettinati HM, Greenberg RM, Crowe RR, Cooper TB, Prudic J.(2001) Continuation pharmacotherapy in the prevention of relapse following electroconvulsive therapy: a randomized controlled trial. JAMA. 2001 Mar 14;
285(10):1299–307.
A 2004 large multicentre clinical follow-up study of ECT patients in New York — describing itself as the first systematic documentation of the effectiveness of ECT in community practice in the 65 years of its use — found remission rates of only 30 to 47 percent, with 64 percent of those relapsing within six months. However, when patients with co-morbid personality disorders or who were suffering from schizoaffective disorder were removed from the analysis, the remission rates climbed to 60-70%.
Related experimental therapeutics
Recent research has investigated whether implantable devices such as those used in DBS (deep brain stimulation) could result in clinical improvements for patients with treatment-resistant depression. However, in North America, DBS has not been authorized as an approved, effective therapy for treatment-resistant depression.
Adverse effects
Aside from effects in the brain, the general physical risks of ECT are similar to those of brief general anesthesia; the U.S. Surgeon General's report says that there are "no absolute health contraindications" to its use.:259 Immediately
following treatment, the most common adverse effects are confusion and
memory loss. The state of confusion usually disappears after a few hours. It can be tolerated by pregnant women who are not suffering major complications. It can be used with diabetic or obese patients, and with caution in those whose cancers are in remission or under control. It can be used in some
immunocompromised patients. It must be used very cautiously in people with epilepsy or other neurological disorders because by its nature it provokes small tonic-clonic seizures, and so would likely not be given to a person whose epilepsy is not well controlled. Some patients experience muscle soreness after ECT. This is due to the muscle relaxants given during the procedure and rarely due to muscle activity. ECT, especially if combined with deep sleep therapy, may lead to brain damage if administered in such a way as to lead to hypoxia or anoxia in the patient.22 The death rate due to ECT is around 4 per 100,000 procedures.23 There
is evidence and rationale to support giving low doses of benzodiazepines or else low doses of general anesthetics which induce sedation but not anesthesia to patients to reduce adverse effects of ECT.
22E. Wilson 2003 Psychiatric abuse at Chelmsford Private Hospital, New South Wales, 1960-1980s. In C. Coleborne and D. MacKinnon Madness in Australia: histories, heritage and the
asylum. Queensland: 121-34
23Gelder, M., Mayou, R., Geddes, J. (2006) Psychiatry. 3rd edition. Oxford: Oxford University Press
Effects on memory
It is the purported effects of ECT on long-term memory that give rise to much of the concern surrounding its use. The acute effects of ECT can include amnesia, both retrograde (for events occurring before the treatment) and anterograde (for events occurring after the treatment).24 Memory loss and confusion are more
pronounced with bilateral electrode placement rather than unilateral, and with outdated sine-wave rather than brief-pulse currents. The use of either constant or pulsing electrical impulses also varied the memory loss results in patients. Patients who received pulsing electrical impulses as opposed to a steady flow seemed to incur less memory loss. A 2007 study on the long term effects of ECT showed that global cognitive impairment followed all forms of ECT in varying extent. The vast majority of modern treatment uses brief pulse currents.
Research by Harold Sackeim has shown that excessive current causes more risk for memory loss, and using right-sided electrode placement may reduce verbal memory disturbance. It was his '07 study that also showed global cognitive impairment in all forms of ECT, including the most benign[citation needed].
Retrograde amnesia is most marked for events occurring in the weeks or months before treatment, with one study showing that although some people lose
memories from years prior to treatment, recovery of such memories was
"virtually complete" by seven months post-treatment, with the only enduring loss being memories in the weeks and months prior to the treatment. Anterograde memory loss is usually limited to the time of treatment itself or shortly
afterwards. In the weeks and months following ECT these memory problems gradually improve, but some people have persistent losses, especially with bilateral ECT. One published review summarizing the results of questionnaires about subjective memory loss found that between 29% and 55% of respondents believed they experienced long-lasting or permanent memory changes. In 2000, American psychiatrist Sarah Lisanby and colleagues found that bilateral ECT left patients with more persistently impaired memory of public events as compared to RUL ECT.
Some studies have found that patients are often unaware of cognitive deficits induced by ECT. For example, in June 2008, a Duke University study was
published assessing the neuropsychological effects and attitudes in patients after ECT. Forty-six patients participated in the study, which involved
neuropsychological and psychological testing before and after ECT. The study documented substantial cognitive impairment after ECT on a variety of memory tests, including "verbal memory for word lists and prose passages and visual memory of geometric designs." Based on their findings, the authors issued the following recommendation:
24Benbow, SM (2004) "Adverse effects of ECT". In AIF Scott (ed.) The ECT Handbook, second edition. London: The Royal College of Psychiatrists, pp. 170–174.
When ECT is provided to adolescents, the potential impact of such cognitive changes should be discussed with the patients and their parents or guardians in terms of implications for not only the patient's emotional functioning but cognitive functioning as well, particularly upon his or her academic
performance. In summary, we argue that an individual cost-benefit analysis should be made in light of the implications of the potential benefits versus costs of ECT upon improving emotional functioning and the impact that potential memory changes may have on real-world functioning and quality of life.
Severe memory loss from ECT is described in an autobiographical book, Doctors of Deception: What They Don't Want You to Know about Shock Treatment.
Controversy over long-term effects on general
cognition
According to prominent ECT researcher Harold Sackeim, "despite over fifty years of clinical use and ongoing controversy", until 2007 there had "never been a large-scale, prospective study of the cognitive effects of ECT." In this first-ever large-scale study (347 subjects), Sackeim and colleagues found that at least some forms (namely bilateral application and outdated sine-wave currents) of ECT "routine[ly]" lead to "adverse cognitive effects," including global cognitive deficits and memory loss, that persist for up to six months after treatment,
suggesting that the induced deficits may be permanent. The authors also warned that their findings did not suggest that right-unilateral ECT did not also lead to chronic cognitive deficits.
Harold Sackeim can be seen in a videotaped deposition briefly discussing the findings of this study and why, in his opinion, earlier studies had failed to find evidence of long-term harm from ECT. Despite over fifty years of clinical use, Sackeim states that prior to 2001, "the field itself never really had an opportunity to have a discussion about patients who have complaints about long-term
memory loss." In this video clip, Sackeim also reveals that at a California ECT conference with 200 practitioners present, when polled as to whether they think ECT can lead to chronic cognitive deficits, two-thirds raised their hands. Sackeim says this was "almost a watershed moment for the field", and was the "first time publicly that the field itself said 'no' to the position that it can't happen."
In July 2007, a second study was published concluding that ECT routinely leads to chronic, substantial cognitive deficits, and the findings were not limited to any particular forms of ECT. The study, led by psychiatrist Glenda MacQueen and colleagues, found that patients treated with ECT for bipolar disorder show
marked deficits across multiple cognitive domains. According to the researchers, "Subjects who had received remote ECT had further impairment on a variety of learning and memory tests when compared with patients with no past ECT. This degree of impairment could not be accounted for by illness state at the time of assessment or by differential past illness burden between patient groups." Despite the findings of chronic, global cognitive deficits in post-ECT patients, MacQueen and colleagues suggest that it is "unlikely that such findings, even if confirmed, would significantly change the risk–benefit ratio of this notably effective treatment."
Six months after the publication of the Sackeim study documenting routine, long-term memory loss after ECT, prominent ECT researcher Max Fink published a review in the journal Psychosomatics concluding that patient complaints of memory loss after ECT are "rare" and should be "characterized as somatoform disorders, rather than as evidence of brain damage, thus warranting
psychological treatment for such disorders." Based on his findings, Fink suggests that, "Instead of endorsing these reports as the direct consequence of ECT,
especially in patients who have recovered from their depressive illness, lost their suicidal drive, and have improved social functioning, is it not more useful to accept the complaint as a somatoform disorder, explore the basis in the
individual's history and experience, and offer appropriate supportive treatment?" A number of reviews of the literature and other articles continue to characterize ECT as safe and effective. For example, in June 2009, Portuguese researchers published a review on the safety and efficacy of ECT in an article entitled, Electroconvulsive Therapy: Myths and Evidences. In their review, the researchers conclude that ECT is an "efficient, safe and even life saving
treatment for several psychiatric disorders." In 2008, Yale researchers published a review on the safety and efficacy of ECT in elderly patients. According to the authors, "ECT is well established as a safe and effective treatment for several psychiatric disorders." And in a June 2009 article published in the Journal of ECT, Iranian researchers observe that, "Despite the wide consensus over the safety and efficacy of electroconvulsive therapy (ECT), it still faces negative publicity and unfavorable attitudes of patients and families."
Breggin, chief editor of the journal Ethical Human Psychology and Psychiatry, is a leading critic of ECT who believes the procedure is neither safe nor effective. In a published article reviewing the findings of Harold Sackeim's 2007 study on the cognitive effects of ECT, Breggin accuses Max Fink and other pro-ECT researchers of having a history of "systematically covering up damage done to millions of [ECT] patients throughout the world." He disagrees with the position that findings of chronic, global cognitive deficits should have no bearing on the risk-benefit ratio of ECT, and he believes it's important to address the "actual impact of these losses on the lives of individual patients." In his 2007 paper, a section is entitled Destroying Lives, and in it, Breggin writes, "Even when these injured people can continue to function on a superficial social basis, they
nonetheless suffer devastation of their identities due to the obliteration of key aspects of their personal lives. The loss of the ability to retain and learn new material is not only humiliating and depressing but also disabling. Even when relatively subtle, these activities can disrupt routine activities of living."
A study published in 2004 in the Journal of Mental Health reported that 35 to 42% of patients responding to a questionnaire reported ECT resulted in loss of intelligence.25 The study also reported, "There is no overlap between clinical and
consumer studies on the question of benefit."
Doctors of Deception: What They Don't Want You to Know About Shock Treatment reports before-and-after IQ testing of persons receiving ECT, including the author, that show 30 to 40 point losses.
Effects on brain structure
Considerable controversy exists over the effects of ECT on brain tissue, although a number of mental health associations — including the American Psychiatric Association — have concluded that there is no evidence that ECT causes
structural brain damage. A 1999 report by the U.S. Surgeon General states, "The fears that ECT causes gross structural brain pathology have not been supported by decades of methodologically sound research in both humans and animals". However, not all experts agree that ECT does not cause brain damage, and two studies have been published since 2007 finding that at least some forms of ECT may result in widespread, persisting, generalized cognitive dysfunction, which might support claims that ECT causes brain damage.
25Philpot M, Collins C, Trivedi P, Treloar A, Gallacher S, Rose D: Eliciting users' views of ECT in two mental health trusts with a user-designed questionnaire. Journal of Mental Health 13(4): 403–413, 2004
Peter Breggin, a psychiatrist, has published books and journal reviews of the literature purporting to show that ECT routinely causes brain damage as
evidenced by a considerable list of studies in humans and animals. In particular, Breggin asserts that animal and human autopsy studies have shown that ECT routinely causes 'widespread pinpoint hemorrhages and scattered cell death.' According to Breggin, the 1990 APA task force report on ECT ignored much of the scientific literature pointing out the negative effects of electroshock therapy. For example, in 1952 Hans Hartelius conducted and published an animal study on cats entitled Cerebral Changes Following Electrically Induced Convulsions in which a double-blind microscopic pathology examination showed that it was possible to distinguish the 8 shocked animals from the 8 non-shocked animals with remarkable accuracy based on statistically significant structural changes to the brain, including vessel wall changes, gliosis, and nerve cell changes. Based on the detection of shadow cells and neuronophagia, Hartelius determined that there was irreversible damage to neurons associated with electroshock.
Proponents argue that the addition of hyperoxygenation and refinement in
technique in the last thirty years has made ECT safe, and a majority of published reviews in recent decades have reflected this position. A 2004 study was
designed to evaluate whether modern ECT techniques lead to identifiable brain damage, In the study: "Twelve adolescent Macaca mulatta, the initial subjects in an ongoing study of the cognitive and anatomic effects of ECT and magnetic seizure therapy, were divided into cohorts of three and matched for age, weight, and sex. Each cohort was housed in a group. Within each cohort, the monkeys were randomly assigned to ECT, magnetic seizure therapy, or sham. All staff not involved in the delivery of the interventions were masked to group assignment. This study was approved by the Institutional Animal Care and Use Committee of New York State Psychiatric Institute. Interventions were performed 4 days per week for 6 weeks. A 5-week recovery period was interposed before the last intervention week to permit maturation of possible neuropathological effects. Animals were euthanized 3 days after the last intervention." Their brains were compared to monkeys undergoing anesthesia alone. According to the
researchers, "None of the ECT-treated monkeys showed pathological findings." Many expert proponents of ECT maintain that the procedure is safe and does not cause brain damage. Dr. Charles Kellner, a prominent ECT researcher and
former chief editor of the Journal of ECT, stated in a 2007 interview that, "There are a number of well-designed studies that show ECT does not cause brain
damage and numerous reports of patients who have received a large number of treatments over their lifetime and have suffered no significant problems due to ECT." Dr. Kellner cites a study purporting to show an absence of cognitive impairment in eight subjects after more than 100 lifetime ECT treatments. Dr. Kellner stated "Rather than cause brain damage, there is evidence that ECT may reverse some of the damaging effects of serious psychiatric illness."
