Cortisol, a corticosteroid, is produced by the adrenal glands and released when the body responds to stress (McEwen & Sapolosky, 1995).  A major function of cortisol is to reestablish homeostasis, however, at high levels cortisol can lead to cognitive deficits.  This is because cortisol has been found to inhibit the uptake of glucose in hippocampal cells, thereby resulting in a loss of their energy source and contributing to early hippocampal cell death (McEwen & Sapolosky, 1995).  Because the hippocampus is an important area of the brain for learning and memory, significant cell loss in this region will contribute to memory deficits (Lupien, deLeon, deSanti, Convit, Tarhish, Nair, Thakur, McEwen, Haugher, & Meaney, 1998).
        Research has established that corticosteroids can contribute to patients’ reports of memory difficulties (Wolkowitz, Reus, Weingartner, Thompson, Breier, Doran, Rubinow, & Pickar, 1990).  Specifically, Wolkowtiz et al. (1990) found that when depressed patients were given dexamethasone they had elevated levels of cortisol, which were associated with significant memory problems.  This suggests that high levels of cortisol will induce cognitive deficits in depressed patients.
        In terms of cognitive deficits, it is interesting to consider whether specific types of memory will be more or less affected by high levels of cortisol.  PET scan studies have established the role of the hippocampal area in object-location memory (e.g, Milner, Johnsrude, & Crane, 1999; Owen & Milner, 1996).  In Owen and Milner’s PET study (1996), they observed that the right hippocampal region was critical for retrieving information that connected an object with its location.  This finding was confirmed by Milner, Johnsrude, and Crane in 1999 using PET scans for a similar object-location memory paradigm.
        The purpose of this study is to determine whether stress induced in the laboratory will trigger the release of cortisol at levels high enough to impair object-location memory.  A noise and demanding cognitive task paradigm similar to Peters and colleagues (1998) to induce stress in college students will be used to test the following hypotheses: (1) the stressor will cause and increase in cortisol for the experimental group, (2) higher cortisol levels will be associated with lower object-location memory scores, and (3) therefore, stress will be associated with lower object-location memory scores.
 
 

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