Brain structure amygdala

Collection of interconnected subcortical and cortical brain structures (including hypothalamus, amygdala, and hippocampus) integrating multimodal intero- and exteroceptive information to produce coherent neuroendocrine and behavioral output, and to support memory functions. 

The amygdala is perhaps the best-studied, and most strongly implicated, brain structure in anxiety and fear. Electrical stimulation of the amygdala produces fear-like behavioral and physiological responses in animals, and increases the suggestive experience of fear in human subjects. Additionally, amygdala stimulation leads to corticosterone secretion and HPA-axis activation in animals, probably via outputs to the hypothalamus and the bed nucleus of the stria terminalis. It has been suggested... 

Note The limbic system is made up of several brain structures, including the hippocampus, amygdala, and basal forebrain (Figure 1.3b). 

A variety of brain structures seem to be essential for aversive memories. In the following, I will briefly introduce the hippocampus and amygdala involvement, without disregarding the importance, for instance, of the cerebellum for eye-blink conditioning (Thompson et al. 1997, 2000 Medina et al. 2002) and the insular cortex for conditioned taste aversion (e.g. Berman and Dudai 2001). 

AD is defined by both neuropathologic and clinical criteria. Neu-ropathologically, AD destroys neurons in the cortex and limbic structures of the brain, particularly the basal forebrain, amygdala, hippocampus, and cerebral cortex. These areas are responsible for higher learning, memory, reasoning, behavior, and emotional control. Anatomically, four major alterations in brain structure are seen ... 

The results presented in different reports point to particular brain structures that have been found to be anatomically affected in autistic persons. These are the cerebellum, the amygdala and the hippocampus [43, 47, 48]. 

The hypothalamus and amygdala, prominently associated with both testosterone and serotonin, play a key role in aggressive responses to situations in which efforts at dominance are frustrated. He notes that low serotonin levels have been found in the hypothalamus and the amygdala in aggressive animals, and that testosterone action in both of these brain structures has been shown to increase aggression in various animal species. ... 

The determination of fhe embryonic "critical period of development" for the brain structures involved in learning and memory processes in mice is based on the original work by Rodier (1976). This study identified fhe embryonic time frames for peak neurogenesis and neuroepithelial proliferation for cerebral corfex, hippocampus, septum, amygdala, corpus striatum, thalamus, hypothalamus, cerebellum, and olfactory bulb as the period from embryonic day E14 fhrough E17. Rodier documented almost 40 years ago that the specific time of the central nervous system (CNS) insult is an important factor in subsequent effects on both anatomy and behavior. Therefore, this early work established what we refer to as the embryonic "critical period of development." The report suggested that the behavioral effects of toxicants such as benzo(a)pyrene (B(a)P) are similar in both rats and mice. This study was one of the first to demonstrate that mice could be used successfully as subjects in a variety of behavioral evaluation experiments. 

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