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

independent of attention, which is used when attentional resources are
constrained. The relationship between emotion and memory may greatly
depend on context (Clark-Foos & Marsh, 2008). Although this study strongly
supports the idea of a causal relationship between attention and the emotional
enhancement of visual specificity of memory of negative items the fact that we
did not independently manipulate attention means that we cannot rule out
alternative explanations.
The attentional and memory effects found with positive emotional
stimuli from this study are not so easily explained as those with negative
emotional stimuli. The enhancement for the details of positive valence objects
was not consistent with Kensinger’s earlier research which reported no
enhancement in memory for details of positive objects (Kensinger et al,
2007a). The effects of negative emotion on memory may be more resilient than
those of positive emotion and this may explain why we replicated the effects
for negative emotion but had different findings with positive emotion.
However, we have now replicated the effect in 3 studies and 2 stimulus sets.
One possibility is that positive stimuli in our experiment differed with
regard to the level of approach motivation to those in Kensinger’s study.
Approach motivation refers to an urge to move toward an object, whereas
withdrawal motivation refers to an urge to move away from an object. The
level of approach motivation induced by positive emotional stimuli can
determine how this emotion influences attention (Gable & Harmon-Jones,
2008) and this could be a route through which different sets of positive stimuli
differentially influence memory. Our stimuli were pre-rated on valence and
arousal and we have measures on approach motivation from the study phase of
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