[Emotion, amygdala, and autonomic nervous system].

Area of Science:

• Neuroscience
• Psychophysiology

Context:

• Emotion is linked to physical and visceral changes regulated by the autonomic nervous system (sympathetic and parasympathetic).
• Understanding emotional states requires monitoring autonomic nervous activity.

Purpose:

• To visualize the neurocircuitry of emotion and identify brain regions regulating emotional stress-induced autonomic activation.
• To explore the role of the amygdala and sex steroids in modulating autonomic responses.

Summary:

• Immediate early genes (IEGs) like c-Fos and viral transneuronal labeling (e.g., pseudorabies virus) visualize emotion neurocircuitry.
• Comparing IEG expression with viral tracing data helps deduce central regulatory sites for stress-induced autonomic activation.
• Key regions identified include the limbic system, hypothalamus, and brainstem nuclei, with the amygdala playing a crucial role.

Impact:

• Identifies specific brain regions within the limbic system, hypothalamus, and brainstem involved in emotional stress and autonomic control.
• Highlights the amygdala's complex role in processing emotional information and its projections to the hypothalamus and sympathetic system.
• Suggests that sex steroids, via receptors in the medial amygdala, may influence autonomic nervous system activity during emotional states.