Hamann S, Mao H. Positive and negative emotional verbal stimuli elicit activity in the left amygdala. NeuroReport 13: 15-19

Department of Psychology, Emory University, Atlanta, Georgia, United States
Neuroreport (Impact Factor: 1.52). 02/2002; 13(1):15-9. DOI: 10.1097/00001756-200201210-00008
Source: PubMed


The human amygdala's involvement in negative emotion is well established, but relatively little is known regarding its role in positive emotion. Here we examined the neural response to emotionally positive, negative, and neutral words using fMRI. Relative to neutral words, positive and negative emotional words elicited greater activity in the left amygdala. Positive but not negative words elicited activity in dorsal and ventral striatal regions which have been linked in previous neuroimaging studies to reward and positive affect, including caudate, putamen, globus pallidus, and accumbens. These findings provide the first direct evidence that the amygdala is involved in emotional reactions elicited by both positive and negative emotional words, and further indicate that positive words additionally activate brain regions related to reward.

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    • ", 2000 ; Tabert et al . , 2001 ; Hamann and Mao , 2002 ; Cunningham et al . , 2004 ; Herbert et al . "
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    • "The human amygdala mediates interaction between the body and the brain during affective processing. The amygdala supports the perception of fear signals and threat (Zald, 2003; Phelps and LeDoux, 2005) and its activity correlates with emotional intensity rating of affective pictures (Phan et al., 2004), including facial expressions (Hamann and Mao, 2002). "
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    • "An unexpected but intriguing finding is the involvement of the left hippocampus and parahippocampal gyrus, including the amygdala. The amygdala is associated with automatic processing of intense emotional stimuli (Citron, 2012; Wager, Phan, Liberzon, & Taylor, 2003; Hamann & Mao, 2002; Garavan, Pendergrass, Ross, Stein, & Risinger, 2001; Adolphs, Russel, & Tranel, 1999); left amygdala activation facilitates successful encoding of emotional verbal material in the hippocampus (Kensinger & Corkin, 2004; Phelps, 2004; Richardson, Strange, & Dolan, 2004), and concurrent activation of these two regions has been associated with the successful retrieval of emotional memories (Dolcos, LaBar, & Cabeza, 2005). Whereas the hippocampus is typically involved in learning and memory (e.g., Moscovitch, Nadel, Winocur, Gilboa, & Rosenbaum, 2006), its activation along with the parahippocampal gyrus has also been shown in studies employing emotional stimuli such as single emotion words (see Citron, 2012, for a review ; Kuchinke et al., 2005) and music (Mitterschiffthaler, Fu, Dalton, Andrew, & Williams, 2007), in which no memory encoding or retrieval task is involved. "
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