from all four lists. Both the initial and final recall showed a recency effect. These results violated the predictions of a short-term memory model, where no recency effect would be expected. Koppenaal and Glanzer (1990) attempted to explain these phenomena as a result of the subjects' adaptation to the distractor task, which allowed them to preserve at least some short-term memory capabilities. In their experiment the long-term recency effect disappeared when the distractor after the last item differed from the distractors that preceded and followed the other items (e.g., arithmetic distractor task and word reading distractor task). Thapar and Greene challenged this theory. In one of their experiments, participants were given a different distractor task after every study item. According to Koppenaal and Glanzer's theory, no recency effect would be expected as subjects would not have had time to adapt to the distractor; yet such a recency effect remained in place in the experiment. Another explanation One proposed explanation for recency in a continual distractor condition, and its disappearance in an end-only distractor task is the influence of contextual and distinctive processes. According to this model, recency is a result of the similarity of the final items' processing context to the processing context of the other items and the distinctive position of the final items versus intermediate items. In the end distractor task, the processing context of the final items is no longer similar to that of the other list items. At the same time, retrieval cues for these items are no longer as effective as without the distractor. Therefore, recency recedes or vanishes. However, when distractor tasks are placed before and after each item, recency returns, because all the list items have similar processing context. Synaptic theory Various researchers have proposed that stimuli are coded in short-term memory using transmitter depletion. According to this hypothesis, a stimulus activates a spatial pattern of activity across neurons in a brain region. As these neurons fire, the available neurotransmitters are depleted..This depletion pattern represents stimulus information and functions as a memory trace. The memory trace decays over time as a consequence of neurotransmitter reuptake mechanisms that restore neurotransmitters to prior levels. Relationship with working memory The relationship between short-term memory and working memory is described by various theories, but the two concepts are generally considered distinct. Neither holds information for long, but short-term memory is a simple store, while working memory allows