The amygdala: vigilance and emotion

Abstract

Here we provide a review of the animal and human literature concerning the role of the amygdala in fear conditioning, considering its potential influence over autonomic and hormonal changes, motor behavior and attentional processes. A stimulus that predicts an aversive outcome will change neural transmission in the amygdala to produce the somatic, autonomic and endocrine signs of fear, as well as increased attention to that stimulus. It is now clear that the amygdala is also involved in learning about positively valenced stimuli as well as spatial and motor learning and this review strives to integrate this additional information. A review of available studies examining the human amygdala covers both lesion and electrical stimulation studies as well as the most recent functional neuroimaging studies. Where appropriate, we attempt to integrate basic information on normal amygdala function with our current understanding of psychiatric disorders, including pathological anxiety. Molecular Psychiatry (2001) 6, 13-34.

Synaptic Gating and ADHD: A Biological Theory of Comorbidity of ADHD and Anxiety

“…On the other hand, impaired synaptic gating by PFC at the accumbens level allows greater access to conditioned amygdala reactions and the anxiety (or aggression) described in some ADHD children. Davis and Whalen (2001) have comprehensively reviewed animal and human literature concerning the role of the amygdala in fear conditioning. They found that the basolateral amygdala is involved in negative and positive affect, as well as spatial and motor learning.…”

Dissociable relations between amygdala subregional networks and psychopathy trait dimensions in conduct‐disordered juvenile offenders

“…The BLA receives information from multiple brain systems and is a site of integration with cortical territories, including those that regulate socioemotional functions [Bzdok et al, 2013; Ghashghaei and Barbas, 2002; LeDoux, 2007; Pessoa, 2011; Sah et al, 2003]. It contributes greatly to the perception, evaluation, and memory formation of emotionally salient events [Davis and Whalen, 2001; LeDoux, 2007; Moul et al, 2012]. The CMA, in contrast, is less heavily integrated with cortical circuits, though its thalamic and insular connections do allow for cortical crosstalks that seemingly shape early information processing [Bienkowski and Rinaman, 2013; Bzdok et al, 2013; Ghashghaei and Barbas, 2002; Keifer et al, 2015; Pessoa, 2011; Sah et al, 2003].…”

“…The CMA, in contrast, is less heavily integrated with cortical circuits, though its thalamic and insular connections do allow for cortical crosstalks that seemingly shape early information processing [Bienkowski and Rinaman, 2013; Bzdok et al, 2013; Ghashghaei and Barbas, 2002; Keifer et al, 2015; Pessoa, 2011; Sah et al, 2003]. It is the primary output site of the amygdala, and orchestrates behavioral and physiological aspects of emotion processing and associative learning via its projections to the brainstem, cerebellum, and hypothalamus [Davis and Whalen, 2001; LeDoux, 2007; Moul et al, 2012]. Noteworthy, recent theories ascribe some of the cognitive and affective deficits in psychopathy to chronic BLA hypoactivity and exaggerated CMA function, which may speculatively be reflected in BLA and CMA functional connectivity [Moul et al, 2012].…”

Predator threat induces behavioral inhibition, pituitary-adrenal activation and changes in amygdala CRF-binding protein gene expression

“…The amygdala is a medial temporal lobe structure that is important in identifying and interpreting cues that are associated with threatening stimuli (Davis and Whalen, 2001;Amaral, 2002;LeDoux, 2003). Considerable evidence implicates the amygdala in conditioned and unconditioned fear responses (Blanchard and Blanchard, 1972;LeDoux, 2000;Davis and Whalen, 2001;Amaral, 2003;Kalin et al, 2004), and human functional imaging studies have demonstrated increased amygdala activation in some patients with anxiety and depressive disorders (Drevets, 2003;Rauch et al, 2003).…”

“…Considerable evidence implicates the amygdala in conditioned and unconditioned fear responses (Blanchard and Blanchard, 1972;LeDoux, 2000;Davis and Whalen, 2001;Amaral, 2003;Kalin et al, 2004), and human functional imaging studies have demonstrated increased amygdala activation in some patients with anxiety and depressive disorders (Drevets, 2003;Rauch et al, 2003). Furthermore, evidence supports a role for the amygdala CRF system in mediating anxiety and fear.…”