ABSTRACT
Humans as well as honey bees need to remember important events to survive. Given limitations of cognitive capacity, however, they also need to forget those moments that are least important. For it is essential in a competitive environment to allocate scarce attentional and memory resources to critical events rather than to the mundane. To be successful when threatened by hungry carnivores, our early mammalian ancestors could not be lost in thought considering the pleasures of the last meal. Similarly, for insects with brains the size of that of a honey bee, not too much memory can be allocated to remembering beautiful sunsets (McGaugh, 1990). The way that motivational and affective reactions to environmental stimuli and outcomes modulate memory seems to be one solution to the problem of remembering critical life events and forgetting the trivial. In the following pages we consider evidence from the personality and motivational literature that suggests that arousal, an intensity component of motivation, has a critical role in modulating the processes involved in the storage and retrieval of information. We propose that high levels of arousal facilitate the detection and long term retention of information but at a seeming cost of inhibiting immediate access to that information. We suggest that because many manipulations of affect and mood are also manipulations of arousal that supposed mood effects upon memory may be accounted for partly by the effect of arousal upon memory. We conclude that some of the controversy surrounding the effects of mood upon memory can be resolved by a proper appreciation of the effects of arousal upon memory.
