What can electrical brain stimulation produce?
Emotional effects
What is the Medial forebrain bundle?
- the tract that rises from the midbrain through the hypothalamus; affected at many self-stimulation sites
What is the Nucleus accumbens?
- Important target for axons of medial forebrain bundle; major component of the reward circuit; release of dopamine here produces very pleasurable feelings
What is decorticate rage?
A sudden intense rage in dogs whose cortex has been removed, suggesting that the cortex inhibits rage
What did James Papez conclude?
that destruction of a set of interconnected brain regions of the limbic system would impair emotional processes
What is Kluver-Bucy syndrome?
characterized by dramatic reduction of fear and anxiety following bilateral amygdala damage
What can classical conditioning elicit?
Can elicit fear, including behaviors and autonomic changes
How can classical conditioning elicit fear?
pairing a stimulus with an aversive(unpleasant) stimulus, like shock
What has studies of fear conditioning identified?
amygdala, located in the temporal lobe, as a key structure in the mediation of fear
Temporal lobe seizures that include the amygdala are preceded by intense fear
What does damage to both amygdalae do to a person?
- Not afraid of spiders or dangerous people
- No startle response
- Only able to recognize emotions other than fear in others
What can fear of love bilaterally affect?
- Increase activity in the insula and anterior cingulate cortex
- Decrease activity in the posterior cingulate and prefrontal cortices
There is no simple, one-to-one relation between a specific emotion and the changed activity of particular brain regions
Exception to the rule: Amygdala and Fear
A study comparing brain activation during sadness, happiness, anger, and fear showed activation where?
In the insula, cingulate cortex, and prefrontal cortex
