Specific attentional impairments and complex visual hallucinations in eye disease.
OBJECTIVE
To test the prediction by the Perception and Attention Deficit (PAD) model of complex visual hallucinations that cognitive impairment, specifically in visual attention, is a key risk factor for complex hallucinations in eye disease.


METHODS
Two studies of elderly patients with acquired eye disease investigated the relationship between complex visual hallucinations (CVH) and impairments in general cognition and verbal attention (Study 1) and between CVH, selective visual attention and visual object perception (Study 2). The North East Visual Hallucinations Inventory was used to classify CVH.


RESULTS
In Study 1, there was no relationship between CVH (n=10/39) and performance on cognitive screening or verbal attention tasks. In Study 2, participants with CVH (n=11/31) showed poorer performance on a modified Stroop task (p<0.05), a novel imagery-based attentional task (p<0.05) and picture (p<0.05) but not silhouette naming (p=0.13) tasks. Performance on these tasks correctly classified 83% of the participants as hallucinators or non-hallucinators.


CONCLUSIONS
The results suggest that, consistent with the PAD model, complex visual hallucinations in people with acquired eye disease are associated with visual attention impairment.
Graham
G
G
Clinical Psychology Programme, University of Teesside, Middlesbrough, UK.
Dean
J
J
Mosimann
U P
UP
Colbourn
C
C
Dudley
R
R
Clarke
M
M
Collerton
D
D
D000368:Aged; D000369:Aged, 80 and over; D001288:Attention / Q000502:physiology*; D010054:Brief Psychiatric Rating Scale; D003072:Cognition Disorders / Q000150:complications* / Q000523:psychology; D003430:Cross-Sectional Studies; D005128:Eye Diseases / Q000150:complications* / Q000523:psychology; D005260:Female; D006212:Hallucinations / Q000209:etiology* / Q000523:psychology; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D012307:Risk Factors