PDF (PhD Thesis Susan Chipchase) - Nottingham eTheses ...

information). Touryan, Marian, & Shimamura (2007) found that the memory
for objects embedded in the periphery of a scene was better for negative than
neutral objects, but that associative memory for these items and their peripheral
information was worse for scenes with a negative than neutral object.
Research by Easterbrook (1959) is often cited as providing support for the
proposal that this attentional narrowing is a defensive motivational reaction to
emotional arousal (e.g. Christianson et al., 1991; Kensinger, Garoff-Eaton, &
Schacter, 2006). It is this motivational reaction which is thought to lead to a
focus on central rather than peripheral elements of a scene. Easterbrook (1959)
investigated animal learning and found that an animal which was aroused by
means of food deprivation became less sensitive to information at the periphery
of an event.
iii) Pre-attentive processes
Studies measuring eye movements have shown that visual attention is
drawn preattentively to emotional, over neutral, pictorial stimuli, suggesting
that emotional content is likely to engage attention in early processing stages
(Nummenmaa, Hyona, & Calvo, 2006). This may lead to a difference in the
amount of information encoded from emotional and neutral stimuli. The
possibility of pre-attentive processing of emotional stimuli (as argued by Kern
et al, 2005) has been directly investigated and it was found that although
affective processing of emotional and non-emotional pictures can occur
without overt attention, some resources for covert attention are required (Calvo
& Nummenmaa, 2007). The ability to process the gist of scenes in peripheral
vision is thought to lead to the selective attentional orienting seen with
emotional stimuli but direct fixations on the stimuli are required to enable
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