Involved in taking actions as response to stressful stimuli More involved in negative emotions
Involved in thought as response to stressful stimuli Involved in recalling details
Named in 1819 an almond-shaped cell mass in the temporal lobe, which is now known as the basolateral complex, the amygdala
They observed that lesions to both temporal lobes resulted in profound changes in fear reactivity, feeding, and sexual behavior
His experiments with rhesus monkeys demonstrated the importance of the amygdala in assigning emotional significance to sensory information
Lesions to the amygdala lead to the disappearance of fear responses
They argued for the concept of an extended amygdala where the central and medial nucleus form a continuous structure with the bed nucleus of the stria termnalis
They claim there is no need to refer to the amygdala as a functional nor as a structural unit within the brain
Some of the behavioral symptoms observed in the past could be due to imprecise surgical procedures, however the amygdala is still crucial for the normal regulation of emotions
People with severely impaired amygdaele have difficulty recognizing emotional expressions particularly from faces that are expressing fear
Developed an animal model of fear conditioning describing two distinct amygdala pathways which he called the low road and the high road
Performed research on how emotional arousal influences memory consolidation, where the amygdala appears to play a key role
Claims that the amygdala is not the fear center of the brain. It's an attentional area involved in detecting ambiguous stimuli that are potentially threatening
Main input station of the amygdala
Largest collection of nuclei in the amygdala
Has output connections to the striatum ventrale and the dorsal-medial nucleus of the thalamus
Involved in memory consolidation
Evolutionary newer part of the amygdala and associated with the neocortex
Comprises the lateral nucleus, the basal nucleus, and the accessory basal nucleus
Interacts with the hypothalamus related to appetitive states
Associated with the olfactory system
Evolutionary older part of the amygdala
Main output station of the amygdala
Smallest collection of nuclei in the amgdala
Has outpunt connections to the lateral hypothalamus and the brain stem
Produces automatic emotional responses
These projections connect the amygdala with several other important brain structures.
The shortcut Involved in associative learning
Association areas of the cortex
The long way around Projects only to subcortical structures Similar in form, function, and location as the fornix for the hippocampal pathway
Could be the result of developmental problems, neurotranmitter imbalance or damage.
The amygdala is normally active, but the prefrontal cortex is unable to calm her down.
amnesia hyperphagia hyperorality hypersexuality docility visual agnosia
Bilateral damage to the medial temporal lobes Disruption in recognizing emotional expressions and in emotional learning
Emotions are blunted, impaired, or absent usually caused by.
Term coined by Daniel Goleman When the hippocampus signals a fight or flight situation, the amygdala triggers the HPA axis which hijacks the rational brain.
The idea of a functionally unified limbic system is grounded on historical concepts of brain anatomy. These concepts are no longer considered to be accurate. It's a group of structures loosely working together in relation to memory and emotion and not a completely integrated system as the name would suggest.