The article ‘Delusions: A
suitable case for imaging?’ by Hadyn Ellis discusses the possibility and
opportunities for using imaging technology for furthering research and
understanding into the nature of delusions associated with recognition and
identification. The belief is that with
using the imaging technologies that are available to hospitals and researchers,
that there could be a link detected between the theoretical processes of
identification and emotional arousal when viewing a familiar face. The type of technology that would be used
would be both spatial and temporal imaging.
The paper is mainly concerned with how these technologies and techniques
can be applied to helping clarify different types of Delusional
Misidentification and the related phenomena, such as covert face
recognition. It is hope also that, in
the process of learning about Delusional Misidentification, it would shed
further light on the process that goes into face, voice, and object
recognition.
The main problem that the
article is addressing, however, is that while there is research backing up the
idea that there should be neuroimaging of people suffering from delusions done,
and that the technology is available, the imaging community has yet to embrace
the ideas and the imaging is not being done.
Ellis is arguing for the imaging community to begin taking the scans of
the delusional people not just for the sake of treating the delusions, but also
in helping to come up with a way to treat and prevent it in others, and also as
a means of learning more about how the mind develops the ability to recognize
and identify voices, objects, and faces. Further, Ellis states that even if the imaging
doesn’t prove to be consistent with the models that have been designed around
the delusional states, the imaging would provide new ways of understanding face
processing which is valuable in and of itself.
The crux of the main
argument that Ellis is making is that whilst the models of the Delusional
Misidentification patients seem sound and to work, there are a few holes in the
models that cannot be explained or solved without the help and use of imaging studies. Ellis goes on to outline the only published
case of an imaging study performed by Lebert and their associates in 1994 which
revealed that there were gross hemispheric changes in blood flow and reductions
in right parietal activity. This was
held constant with a later study by Ellis that showed that there were slower
responses in patients that were shown two faces tachistoscopically in the left
field of vision, but that there was no difference in the right. Ellis then goes on to argue that while these
results are good, they are not enough to go on, and that there needs to be a
more sophisticated and systematic method and means of investigation. Ellis states that there are many fMRI studies
that have revealed the role that the lateral fusiform gyrus and the temporal
cortex plays in facial processing, and that even with this information, there
are no systematic imaging processes or studies being done to further this model
or the line of work in neuropsychiatry in relation to the delusional states, even
though the equipment is readily available and there has been marked signs that
such a procedure and study would be pertinent.
In conclusion, Ellis makes a
very good point about the lack of imaging research and studies that are being
done on those who have delusional misidentification problems. There is no reason why the imaging studies
could not be performed in the manner that Ellis is recommending, especially
since the equipment is already available and there is data to show that such
studies would be good to have. The weak
spot in the argument, however, is not lack of data on Ellis’ part, but rather
too much in a technical form. Ellis is
very thorough in researching statistics and methods and past models, however,
the amount of raw data that is used in this article makes it difficult, or at
least tedious, to read and get to the point that Ellis is trying to make.
Bibliography
Ellis, H. (2007). ‘Delusions: A suitable case for imaging?’ in International Journal of
Psychophysiology, No.63, pp.
146-151.
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