Km. Hartikainen et al., Transient interference of right hemispheric function due to automatic emotional processing, NEUROPSYCHO, 38(12), 2000, pp. 1576-1580
We examined the effects of emotional stimuli on right and left hemisphere d
etection performance in a hemifield visual discrimination task. A group of
18 healthy subjects were asked to discriminate between upright and inverted
triangles (target). Targets were randomly presented in the left or right v
isual hemifield (150 ms target duration). A brief emotional picture (pleasa
nt or unpleasant; 150 ms stimulus duration) or neutral picture selected fro
m the International Affective Picture System was randomly presented either
in the same (47%) or the opposite (47%) spatial location to the subsequent
target. Emotional or neutral stimuli offset 150 ms prior to the subsequent
target. Subjects were instructed to ignore the pictures and respond to the
targets as quickly and accurately as possible. Independent of field of pres
entation, emotional stimuli prolonged reaction times (P < 0.01) to LVF targ
ets, with unpleasant stimuli showing a greater effect than pleasant stimuli
. The current study shows that brief emotional stimuli selectively impair r
ight hemispheric visual discrimination capacity. The findings suggest autom
atic processing of emotional stimuli captures right hemispheric processing
resources and transiently interferes with other right hemispheric functions
. (C) 2000 Elsevier Science Ltd. All rights reserved.