Abnormal somatosensory processing in schizophrenia : changes in somatosensory sensitivity on a shortened version of the Kinaesthetic Figural Aftereffects task.
Date
2010-11-10
Authors
Spyrelis, Alexandra
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Abstract
The current study examined somatosensory processing in 32 schizophrenic patients and 32 mentally healthy controls using a shortened version of the Kinaesthetic Figural Aftereffects task (KFA), in order to determine whether the shortened instrument could discriminate significantly (as the original, longer version does) between schizophrenic sufferers and healthy controls in terms of variations of sensory sensitization following satiation, as well as to establish whether it had the same internal consistency as the original version of the instrument. A self-adapted KFA, using a larger estimate block was also used as a repeated measures component, in order to determine whether it would provide evidence for the test-retest reliability of the shortened version of the KFA. A significant difference was found between the two groups in terms of their somatosensory processing, in the expected direction, with the significant majority of controls showing an increase in their post-satiation estimates of stimulus size, while schizophrenic participants showed either no pattern or a reduction in post-satiation estimates, confirming the wealth of findings in this area, and providing some reliability data for the shortened instrument. These findings were discussed within the framework of Meehl’s theory of schizotaxia, as well as that of the sensory gating theory in schizophrenia, as well as sensory integration theories. Methodological limitations of the study as well as apparently contrasting findings with the self-adapted version of the task mean that results should be interpreted with caution. Suggestions for further research were recommended.