Wednesday, 16 December 2009

Skills and interests

Right, time to focus a little more specifically on what I actually want to do (i.e. which techniques to use) during this PhD.

I want to utilise:
  • Evolutionary computation
  • Neural networks
    • Hence --> evolving neural networks
  • Methodical experimentation rather than "one great big long think"
This lends itself to the idea of heuristically creating or refining a model to fit a certain fitness function (e.g. expected behaviour of the network under certain conditions).


The fields in which I am particularly interested in using these techniques are:

  • Understanding more about Alzheimer's disease
    • Model of robustness of musical memory in AD?
      • Nothing obviously defined in the literature, but it could be over-ambitious to hope to model musical memory sufficiently in the time available for the PhD.
    • Models of progression?
      • Already many models defined -- probably end up refining or combining existing models.
  • OR understanding more about schizophrenia
    • Model of ability of music to calm patients in both AD and schizophrenia?
      • Nothing obviously defined in the literature, but it could be over-ambitious to hope to model musical processing sufficiently in the time available for the PhD.
    • Models of hallucinations?
      • Already many models defined -- probably end up refining or combining existing models.
  • OR investigating the overlap between aspects of AD and schizophrenia
    • Model of potential degenerative processes in both disorders?
      • Degenerative process in schizophrenia postulated in Rund (2009).
      • Possible supporting evidence for reduced cortical synaptic connection in schizophrenia (Hoffman and McGlashan (2001)) and reduced hippocampal synaptic connection in Alzheimer's disease (Duch (2007) and Wallenstein and Hasselmo (1997)) both leading to runaway synaptic modification (Hasselmo (1994)).
      • Would need to show how the runaway synaptic modification follows the same basic pathology but diverges to form the two separate disorders.
      • Needs further reading to investigate the initial feasibility of this hypothesis, or whether it's easy to disprove.
Well, having written all that down, it looks like the above question (modelling degenerative processes in AD and schizophrenia) actually could present quite a good topic. (On an unrelated note, why is it that I can spend a day moping around, staring blankly at some papers and not really getting much done, but as soon as I sit down and start to write here, ideas come flowing forth?)

For the time being, at least, if I read further into the possibility of a neuropathalogical overlap in AD and schizophrenia, I can get an idea for how feasible as a hypothesis this is (at the moment it's not much more than a hunch, having read through a few related papers).

I'll also need to figure out how I'll actually go about testing any hypothesis in this area experimentally, as I still want to make use of the refine-and-repeat evolutionary computation technique for generating candidate networks according to the rules of whatever model I end up using / designing.

References
Rund, B.R. (2009), "Is there a degenerativeprocess going on in the brain of people with schizophrenia?" in Frontiers in Neuroscience.

Wallenstein, G.V. and Hasselmo M.E. (1997), "Are there common neural mechanisms for learning, epilepsy, and Alzheimer's disease?", in Stein and Ludik (1997),  pp. 314--316.

Stein, D.J. and Ludik, J. (1998), Neural Networks and Pyschopathology, Cambridge University Press.

Duch, W. (2007), "Computational Models of Dementia and Neurological Problems", in Methods in Molecular Biology, pp. 305--336.

Hoffman, R.E. and McGlashan, T.H. (2001), "Neural network models of schizophrenia", in Neuroscientist 7(5):441--454.

Hasselmo, M.E.  (1994), "Runaway synaptic modification in models of cortex: Implications for Alzheimer's disease", in Neural Networks 7:13--40.

No comments:

Post a Comment