Animal memory and animal welfare

Retrieved memories of emotionally laden events are likely to influence the ongoing emotional state and behaviour of animals. If animals consciously ex perience memories and/or associated emotions, then recall of aversive or pl easurable events will affect their welfare. Even if they do not, retrieval of these (non-conscious/implicit) memories may result in behaviour such us attempts to escape, that could lead to injury and damage. There is growing evidence that emotionally laden events are more readily stored in memory th an neutral ones, and that the neurophysiological basis of this, involving a cute elevations of the classic stress hormones and the action of the amygda la, is similar in humans and other vertebrate species. Thus, in humans and animals, emotional memories are likely to be stored as priority information and may readily be retrieved in the presence of relevant cues. If so, an i mportant practical goal is to minimize the chances of negative emotional me mories being cued inappropriately, especially for animals in captivity. Dis ruption of memory formation and retrieval is also important in an animal we lfare context. Chronic or very high elevations of stress hormones appear to have both short- and long-term effects on brain structure and function tha t carl interfere with efficient storage of information. Environmental distu rbances, including common husbandry procedures, can also disrupt memory, fo rmation through retroactive interference effects. Elevated stress levels ma y, both increase the chances of retrieval of negative information while ham pering the retrieval of positive or neutral information. These effects may lead to poor learning abilities, selective or disrupted memory retrieval, a nd consequent inappropriate behaviour with adverse welfare consequences. If we understand them, we may be able to recommend housing or husbandry, proc edures that minimize the likelihood of their occurrence.