The past 15-20 years has witnessed an impressive convergence of animal and human subject studies concerning brain mechanisms storing "emotional memory," defined here as explicit memory for emotionally arousing events. Extensive evidence implicates stress hormones and the amygdala as key, interacting components of an endogenous 'memory modulating'mechanism. Our recent research also uncovered significant sex and sex hormone influences on these mechanisms. Here we propose to further investigate the neural underpinnings of emotional memory with a combination of basic and applied studies, broadly divided into 3 parts. The first will investigate sex/stress hormone influences on emotional memory, including in patients deprived of sex hormones for cancer treatment. The second will examine neurohormonal underpinnings of intrusive recollections that occur after emotional events, and examine whether sex hormones influence the development of intrusive recollections in recently traumatized women. The third will utilize a method we have recently developed for selectively disrupting both emotional memory and amygdala effective connectivity (namely, a targeted dose of the anesthetic sevoflurane) to further dissect amygdala contributions to emotional memory in healthy humans. Collectively, these studies should provide broad new insight into neural mechanisms of emotional memory storage, and into sex influences thereto. They should also help minimize the gap that still exists between basic and applied studies of emotional memory.

Public Health Relevance

Research like ours into brain mechanisms of emotional memory, and sex influences on those mechanisms, has immediate, strong relevance for understanding and treating many disorders of emotional memory, most notably Posttraumatic Stress Disorder (PTSD) and clinical depression. Our research involving sex/stress hormone interactions in memory will also help us understand, and treat, the severe memory deficits commonly experienced in cancer patients who are deprived of sex hormones as part of their therapy.

National Institute of Health (NIH)
National Institute of Mental Health (NIMH)
Research Project (R01)
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Biobehavioral Mechanisms of Emotion, Stress and Health Study Section (MESH)
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Simmons, Janine M
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University of California Irvine
Other Basic Sciences
Schools of Arts and Sciences
United States
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Nielsen, Shawn E; Ahmed, Imran; Cahill, Larry (2014) Postlearning stress differentially affects memory for emotional gist and detail in naturally cycling women and women on hormonal contraceptives. Behav Neurosci 128:482-93
Petersen, Nicole; Kilpatrick, Lisa A; Goharzad, Azaadeh et al. (2014) Oral contraceptive pill use and menstrual cycle phase are associated with altered resting state functional connectivity. Neuroimage 90:24-32
Nielsen, Shawn E; Segal, Sabrina K; Worden, Ian V et al. (2013) Hormonal contraception use alters stress responses and emotional memory. Biol Psychol 92:257-66
Nielsen, Shawn E; Ahmed, Imran; Cahill, Larry (2013) Sex and menstrual cycle phase at encoding influence emotional memory for gist and detail. Neurobiol Learn Mem 106:56-65
Ertman, Nicole; Andreano, Joseph M; Cahill, Larry (2011) Progesterone at encoding predicts subsequent emotional memory. Learn Mem 18:759-63
Andreano, Joseph M; Cahill, Larry (2010) Menstrual cycle modulation of medial temporal activity evoked by negative emotion. Neuroimage 53:1286-93
Cahill, Larry (2010) Sex influences on brain and emotional memory: the burden of proof has shifted. Prog Brain Res 186:29-40
Ferree, Nikole K; Cahill, Larry (2009) Post-event spontaneous intrusive recollections and strength of memory for emotional events in men and women. Conscious Cogn 18:126-34
Segal, Sabrina K; Cahill, Larry (2009) Endogenous noradrenergic activation and memory for emotional material in men and women. Psychoneuroendocrinology 34:1263-71
Andreano, Joseph M; Arjomandi, Hamidreza; Cahill, Larry (2008) Menstrual cycle modulation of the relationship between cortisol and long-term memory. Psychoneuroendocrinology 33:874-82