CHAPTER 4: DISCUSSION
4.5 Future Directions
Some of the limitations mentioned above could potentially be addressed by future
mediational model such as the one described in the current paper could provide a
wealth of information regarding the process of neurodegeneration and how that relates
specifically to cognition and functional outcome. The current study demonstrates that it
is possible to delineate a specific relationship leading from neuroanatomy to cognition
and finally to functional abilities. Adding an understanding of how these processes
evolve over time could have important implications for treatments that might allow
individuals to optimize their level of functioning. Despite the obvious benefit of such a
research project, clear obstacles to such research would include the difficulty of
obtaining sufficient neuroimaging data and limiting loss of subjects over time. For that
reason, cross sectional designs that include degree of dementia as a variable could also
provide important clues regarding the process of neurodegeneration and how it relates
to cognition and IADLs.
While the current study examined WMI within a small area of the DLPFC and
treated it as an isolated structure, future studies could look at white matter pathways
connecting significant brain areas in an effort to better understand the process of
degeneration. In other words, the research could focus more on networks and
connections that might be susceptible to degeneration and attempt to understand how
they are related to cognition and adaptive functioning. Given the relationship
established between WMI in the DLPFC and executive functioning/ IADLs in the current
study, future research could use tractography originating with the DLPFC as a starting
point.
In general, the current study has important implications for future research.
microstructure and to outline a specific relationship leading from neuroanatomy to
cognition and ultimately, ability to perform day to day functioning. As such, other
researchers can be encouraged to employ mediational models in their own research.
Clinically, it is hoped that this research and future research using the same
methodology, may provide important clues for targeted treatment interventions. A better
understanding of the neurodegenerative process and related cognitive decline may
assist in earlier identification of the disease and implementation of treatment with the
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