Reality monitoring in anosognosia for hemiplegia.
Anosognosia for hemiplegia (AHP) is a lack of awareness about paralysis following stroke. Recent explanations use a 'forward model' of movement to suggest that AHP patients fail to register discrepancies between internally- and externally-generated sensory information. We predicted that this failure would impair the ability to recall from memory whether information is internally- or externally-generated (i.e., reality monitor). Two experiments examined this prediction. Experiment 1 demonstrated that AHP patients exhibit a reality monitoring deficit for non-motor information (i.e., perceived vs. imagined drawings), whilst hemiplegic controls without anosognosia (nonAHP) perform like age-matched healthy volunteers (HVs). Experiment 2 explored if this deficit occurs when AHP patients discriminate performed, imagined, or observed movement. Results showed impaired reality monitoring for movements in AHP and nonAHP patients relative to HVs. Findings suggest that reality monitoring processes not directly related to movement, together with a failure to reality monitor movements, contribute to the pathogenesis of AHP.
Jenkinson
Paul M
PM
School of Psychology, Research Institute for Life Course Studies, University of Keele, Staffordshire ST5 5BG, UK. p.m.jenkinson@psy.keele.ac.uk
Edelstyn
Nicola M J
NM
Drakeford
Justine L
JL
Ellis
Simon J
SJ
D000368:Aged; D000377:Agnosia / Q000523:psychology*; D001288:Attention; D001364:Awareness; D001828:Body Image; D003469:Culture; D004192:Discrimination, Psychological; D005260:Female; D007839:Functional Laterality; D006429:Hemiplegia / Q000523:psychology*; D006801:Humans; D007092:Imagination; D007600:Judgment; D007699:Kinesthesis; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D010364:Pattern Recognition, Visual; D011597:Psychomotor Performance; D011936:Reality Testing; D020521:Stroke / Q000523:psychology