Electrophysiological evidence for changes in attentional orienting and selection in functional somatic symptoms

Objective
We investigated changes in attention mechanisms in people who report a high number of somatic symptoms which cannot be associated with a physical cause.
Method
Based on scores on the Somatoform Disorder Questionnaire (SDQ-20; Nijenhuis et al., 1996) we compared two non-clinical groups, one with high symptoms on the SDQ-20 and a control group with low or no symptoms. We recorded EEG whilst participants performed an exogenous tactile attention task where they had to discriminate between tactile targets following a tactile cue to the same or opposite hand.
Results
The neural marker of attentional orienting to the body, the Late Somatosensory Negativity (LSN), was diminished in the high symptoms group and attentional modulation of touch processing was prolonged at mid and enhanced at later latency stages in this group.
Conclusion
These results confirm that attentional processes are altered in people with somatic symptoms, even in a non-clinical group. Furthermore, the observed pattern fits explanations of changes in prior beliefs or expectations leading to diminished amplitudes of the marker of attentional orienting to the body (i.e. the LSN) and enhanced attentional gain of touch processing.
Significance
This study shows that high somatic symptoms are associated with neurocognitive attention changes.

© 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V.
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