Recent research has revealed how cognition and auditory function are inextricably linked with consequent effects on written and verbal communication, social interaction, understanding and other learning that extend beyond the mere processing of sound (Kraus, Strait & Parbery-Clark, 2012). Auditory function describes the different processes involved in the perception, discrimination and processing of auditory stimuli (hearing), which require memory and recognition (listening) in order to make sense and draw meaning from sounds. While hearing relies on a bottom-up process of
unconscious detection of auditory stimuli, so listening relies on top-down process of conscious recall and recognition in order to derive meaning from different sounds. This requires previous knowledge and experience. Over time, streams of auditory
information become associated with actions and understanding and act as the reference to predict, make sense and respond to sound appropriately. It is a highly sensitive and dynamic multi-sensory process that depends on the accurate detection of auditory, visual and kinaesthetic stimuli coordinated through the vestibular function in the ear. Thus, listening and hearing are separate but interdependent processes, essential for the development of good auditory function and by association, cognitive, physical, social, and emotional development.
Auditory function is known to be central to the development of key skills involved in speech and language development (Goswami, Wang, Cruz, Fosker, Mead & Huss, 2010; Jakobsen, Cuddy, & Kilgour, 2003; Magne, 2006; Wong, Skoe, Russo, Dees & Kraus, 2007); literacy (Corriveau & Goswami, 2009; Ziegler & Goswami, 2005), memory (Chan et al., 1998; Ho et al., 2003) and emotional understanding (Banai, Hornickel, Skoe, Nicol, Zecker, & Kraus, 2009; Goswami, 2010). Auditory function has also been shown to be a predictor of future reading ability (Corriveau & Goswami, 2009). These are all areas that correspond to key priorities in mainstream learning support provision outlined in Chapter One.
Critical to the development of auditory function is the ability to rapidly distinguish similarities and differences in signal-based cues such as timbre, harmonics, frequency, pitch and volume over time and in space, through the identification of repeating or sequential patterns that require attention and involve both working and semantic
memory. Parsing these similarities and differences from a stream of sound relies on the ability to identify silence as well as sound. Trevarthen (2000) observes that it is these
millisecond gaps which help to group different elements of the signal into identifiable, predictable patterns of information required for speech and language, reading, spelling, numeracy, emotional understanding and motor control.
2.3.1 The Importance of Early Auditory Learning
Auditory perception develops before birth and is fully functional between 24-28 weeks gestation (Lecanuet, 1996). As a consequence of auditory learning that takes place in utero, centred on the regularity of the mother’s heartbeat and physiological functions (DeNora, 2000), new-borns are able to detect their mother’s voice and have been shown to respond to other environmental and musical sounds heard whilst in the womb
(Lecanuet, 1996). New-borns learn the fundamentals of speech and language through the recognition of prosodic elements in the instinctive sing-song style of communication between parent and infant known as motherese (Fassbender, 1996; Lecanuet,1996; Papousek, 1996; Trehub et al., 1997).
Motherese is characterised by repetitive, rhythmic intonation, undulating pitch sounds of short durations with the melody conveying the message; the latter of which is one of the first elements infants learn to discriminate (Trehub, Bull & Thorpe, 1984).
Rhythmic regularity helps the infant to synchronise their sounds to their parents in “protoconversations” that are fused to a shared inner beat (Trevarthen, 2000, p. 197). By six months old, infants can discriminate emotions in others through vocal, physical and tactile cues and can discern differences in tonality, tempo, pitch and timbre. Trevarthen acknowledges that whilst parent and child are not making music in the traditional sense, he argues it is through the rhythmic and social nature of these early ‘musical’ exchanges that a child learns fundamental discriminatory skills, centred on what he describes as the Intrinsic Motive Pulse (IMP). Trevarthen argues that IMP is at the heart of human innate musicality, driving individual actions and awareness and making music “meaningful, memorable and above all shareable” (p.158), by linking actions to emotions associated with specific objects, people and events. Singing lullabies or nursery rhymes, rocking, clapping or bouncing on a parent’s lap appear to support this cognitive and social development, helping to develop a sensitivity to beat and metre perception in the first year of life. However some evidence suggests this may be an innate skill evident in newborn infants, a few days old (Honing, 2012). This is a key issue, raised in the Introduction to this chapter, as to whether such auditory
Trevarthen (2000) argues that withdrawal of the early interactions between mother and child outlined above or an inability to lock on to the inner beat can lead both infant and mother to exhibit negative emotions and distress. Sensory or physical impairment, social deprivation, postnatal depression or poor quality childcare may also hamper or deprive a child of these vital early social interactions with potential longer-term
ramifications for cognitive development, health and wellbeing discussed further below. Nevertheless, singing, movement and rhythm, simple and innocuous as they seem, appear to be at the heart of the complex processes involved in auditory learning that shape how we think, react, learn and interact with the world.
2.3.2 The Impact of Disrupted Auditory Function
As outlined above, research suggests that children with learning difficulties are often associated with disrupted auditory function or auditory processing disorder (Bradlow, Kraus & Hayes, 2003; Cunningham, Nicol, Zecker, Bradlow & Kraus, 2001; Hayes, Warrier, Nicol, Zecker & Kraus, 2003; Wible, Nicol & Kraus, 2004). Auditory function is vulnerable to disruption as the brain continues to develop into late adolescence. Echoing Trevarthen’s theories, early auditory deprivation is also thought to derive from exposure to excessive noise in the Neonatal Intensive Care Unit (NICU) at a critical point in an infant’s auditory development, outside the normal protection afforded by the mother’s womb. Such deprivation is thought to “alter brain structure and subsequently account for some of the hearing, language and attention deficits often seen in NICU graduates” (McMahon, Wintermark & Lahav, 2012, p.19).
As outlined above, auditory function is a complex process involving bottom-up and top- down processing, such that disruption can occur in a variety of ways at different points, requiring a multi-disciplinary approach to diagnosis and support (Bamiou, Musiek, Luxon, 2001; Chermak, 2001). In contrast to deaf children who experience hearing loss, children with processing difficulties may have perfect hearing. Such difficulties may be manifested in a number of other ways. For example, poor recognition of the incoming signal leads to storage of a poor representation in short and long term memory that in turn results in a mismatch and inability to recognise, predict and recall previously inaccurately stored signals. A lack of synchrony between the ears can lead to difficulty with speech, word recognition and manipulation, rhyming, and sound segmentation (Oglethorpe, 2002), or blending sounds (Bregman, 1993), which can impact upon spelling, reading and literacy. Poor auditory function may be evident in a range of difficulties that appear outwardly less connected to auditory function, namely a lack of
attention, poor handwriting or general clumsiness, through a lack of spatial awareness or poor motor coordination. Misunderstanding instructions as a result of missing emotional cues in the signal, or difficulty in distinguishing the teacher’s voice from another in a noisy classroom, all may impact on social behaviour. Over time constant mismatching slows the process of recognition and recall and leads to the individual being in a constant state of catch-up, which can be exhausting, demotivating and debilitating, leading an individual to withdraw. Alternatively, such mismatching can lead the brain to be in a constant state of alert, seeking information to resolve the mismatch, which can lead to an inability to concentrate, to sit still or act appropriately. Nevertheless, auditory function is known to be plastic and has been shown to be
responsive to training (Gaab, Gabrieli, Deutsch, Tallal & Temple, 2007; Hayes, Warrier, Nicol, Zecker & Kraus, 2003; Nicol & Kraus, 2005; Russo, Hornickel, Nicol, Zecker & Kraus, 2010; Russo, Nicol, Zecker, Hayes & Kraus, 2005; Warrier, Johnson, Hayes, Nicol & Kraus, 2004), with transferable benefits to other learning. It is here where it is argued music may be able to make a positive contribution in supporting the development of good auditory function through the development of similar cognitive and sensory processes involved in both musical learning and auditory-based learning.