Anxiety is a feeling of apprehension, dread or fear. A moderate amount of short term anxiety can enhance concentration and memory. However, when the anxiety is chronic and low level, such as that arising from an unhappy marriage or an unfulfilling job, cognitive impairment can result from a dulling of the senses. One consequence of this is impaired memory.

One target of chronic anxiety on the brain, evidence suggests, is the hippocampus -a pair of structures that play a key role in the transformation of experiences and perceptions into enduring memories. Studies suggest that prolonged anxiety can kill or retard the growth and activity of cells in the hippocampus.