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

faces or places (Puri & Wojciulik, 2008). Although there was no influence on
performance when participants were cued with just the general category, rather
than a specific example.
ii) Distinctiveness of emotional stimuli
Another possibility is that emotional stimuli may differ to other stimuli
in an experiment with regard to their relative distinctiveness. This concept was
initially discussed in chapter 2 of this thesis, where emotional stimuli were
presented in blocked lists and we argued that some of the difficulty in finding
emotional effects in memory may have been due to this element of the
experimental design. It has been argued that at least some of the memory
effects attributed to emotion were actually due to item distinctiveness
(Schmidt, 2002). Dewhurst & Parry (2000) found an emotional enhancement
for positive and negative words in the number of correct Remember responses,
but not correct Know responses with mixed lists. However, when blocked lists
of positive, negative or neutral words were used Dewhurst & Parry (2000)
found that the emotional enhancement was eliminated. This was due to higher
recognition of neutral items with blocked lists rather than lower recognition of
emotional items. Similar elimination of an emotional enhancement has been
found by presenting emotional pictures in pure rather than mixed lists (Talmi et
al., 2007).
Schmidt & Saari (2007) investigated why distinctiveness of emotional
stimuli may lead to this effect. Possibilities considered include the
interpretation that distinctive/emotional material receives increased processing
relative to common/neutral material; there may be a contrasting memory
representation between distinctive and common information or that the
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