Summary:
Hallucinations have been documented as a very common non-motor symptom in the
course of Parkinson’s disease (PD). The present study examines whether PD
patients, who report having experienced hallucinations or misperceptions,
declare specific selective attention deficits. We evaluated thirty one
patients, regarding the presence of hallucination or not, and then assessed
their selective attention and visual perception with Ruff 2 & 7 test and HOOPER
plus Judgment of Line Orientation test, respectively.
Between the hallucination-free and hallucination-plus group, none statistically
significant difference noted, as far as the selective attention domain was
concerned. When we further divided the hallucination-plus population in two
subgroups (plus minor and plus formed hallucination), the performance of the
three groups in the selective attention task was comparable, while the
previously noted difference in the object recognition task was obscured [F (2,
28) = 3.01, p=.065]. Interestingly, that new categorisation disclosed a
statistically significant lower performance in the position discrimination test
on behalf of PD patients with formed hallucination [F (2, 28) = 4.20, p= .025].
Our findings did not reveal impaired selective attention as a potential trigger
factor of hallucinations in PD patients, probably because of the sensitivity of
our test in a specific form of selective attention. However, our results
regarding deficits in visuoperceptive and visuospatial tasks were in agreement
with previous studies.
Keywords:
Parkinson's disease, Visual hallucinations, Selective attention, Visuospatial perception , Attentional networks
