杏仁核，Amygdala，或叫杏仁體，Amygdaloid body，左右各一，形似杏仁（Almond，扁桃樹(shù)的果仁）。杏仁核屬于大腦內(nèi)部的基底核（Basal ganglia）。位于顳葉海馬的更深面，部分與尾狀核尾相連。杏仁核是邊緣系統(tǒng)（the limbic system）的皮質(zhì)下中樞部分，與行為、情緒、記憶等有關(guān)。
The amygdala is a complex structure of cells nestled in the middle of
the brain, a roughly almond-shaped mass of gray matter inside each cerebral hemisphere, adjacent to the hippocampus (which is associated with memory
formation). It is part of the limbic system and plays a key role in
processing emotions and emotional reactions.
杏仁核（amygdala），位于前顳葉背內(nèi)側(cè)部，海馬體（hippocampus）和側(cè)腦室下角頂端稍前處。主要通過(guò)外側(cè)嗅紋、終紋和腹側(cè)杏仁傳出通路，與額葉內(nèi)側(cè)、眶額回、隔區(qū)、無(wú)名質(zhì)、視前區(qū)、海馬體、下丘腦、丘腦、紋狀體、顳蓋皮質(zhì)、島蓋皮質(zhì)、頂蓋皮質(zhì)、顳極、運(yùn)動(dòng)皮質(zhì)及腦干網(wǎng)狀結(jié)構(gòu)等有雙向交互聯(lián)系。
杏仁核是大腦基底神經(jīng)核的一個(gè)重要核團(tuán)，為邊緣系統(tǒng)的組成部分，含有13個(gè)大小不等的核團(tuán)。按照其位置與功能分為基底外側(cè)核群、皮質(zhì)內(nèi)側(cè)核群、杏仁前區(qū)和皮質(zhì)杏仁移行區(qū)4部分。
杏仁核的神經(jīng)網(wǎng)絡(luò)
杏仁核的傳入纖維主要起始于嗅球（Olfactory bulb）及嗅前核、基底前腦Meynert核的膽堿能神經(jīng)元、腦干、中腦腳間核、臂旁核、腦橋藍(lán)斑（Locus Coeruleus）、中腦中縫核（Nucleus Raphe mediale）及腹側(cè)背蓋、下丘腦的腹內(nèi)側(cè)核（The ventromedial nucleus of the hypothalamus）、丘腦中線(xiàn)核群及丘腦腹后內(nèi)側(cè)核（Ventroposteromedial nucleus of thalamus）等。
杏仁核的大部分傳出纖維與傳入纖維呈往返聯(lián)系，一般認(rèn)為杏仁核通過(guò)兩條路徑傳出信號(hào)：終紋通路（stria terminalis），起自皮質(zhì)內(nèi)側(cè)核，呈弓形彎于尾核內(nèi)側(cè)緣與丘腦之間，向前終止于終紋核（stria terminalis）、下丘腦（尤其是室旁核、視上核）、視前區(qū)及隔核；腹側(cè)杏仁核傳出徑路（ventral amygdalofugal pathway）主要起自基底外側(cè)核，纖維多且散在，有些向內(nèi)側(cè)止于終紋床核的內(nèi)側(cè)部；有些向前止于視前區(qū)、下丘腦（腹內(nèi)側(cè)核）、丘腦背內(nèi)側(cè)核，繼而到額前皮質(zhì)及其他皮質(zhì)聯(lián)絡(luò)區(qū)。此外，杏仁核內(nèi)部還有十分復(fù)雜的固有纖維聯(lián)系。
（labeled in blue）
The amygdala is a very well studied part of the limbic system and forms part of the mesial temporal lobe. The amygdala is a complex grey matter structure located anterior and superior to the temporal horn of the lateral ventricle and head of the hippocampus. The anterior extension of the amygdala is identified by the entorhinal sulcus. Both the amygdala and the hippocampus are derived from the telencephalon. In 1997, Gloor classified the amygdala into three large groups of nuclei: basolateral,corticomedial (phylogenetically the oldest), central group.
（Amygdalar enlargement in patients with temporal lobe epilepsy） 杏仁核的生理功能 When
we perceive something threatening, the thalamus sends sensory information tothe amygdala, which triggers a fear response. The amygdala activates thesympathetic nervous system, initiating our fight-or-flight reaction. It also
signals the hippocampus to store memories of the fearful event so we can avoid
similar threats in the future.
Memory Formation An
area in which the amygdala is most prominent is the formation of memories,
especially those that are emotional. As
the amygdala is remarkably close to, and forms connections with the hippocampus
(a memory structure of the brain), these two often work together to make
memories more memorable.
Emotion LearningThe amygdala plays a distinctive role in mediating many aspects of
emotional learning as well as emotional behavior. An emotion the
amygdala is particularly responsible for is controlling fear. Aggression The amygdala is the most important part of the limbic system for many emotions, including aggression. FearThe amygdala’s role in psychopathy has been a major topic of study in
neuroscience for many years. Historically, the amygdala was believed to
be the “fear center” of the brain, responsible for experiences and
behaviors related to fear (Kiehl, 2006).
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