Task 5 Flashcards
What main brain structures make up the limbic system?
- Amygdala
- Hippocampus
- Cingulate Gyrus
- Hypothalamus
Which amygdala sub-nucleus has connections to olfactory circuits?
Medial Nucleus
Which amygdala sub-nucleus is the input site for thalamic projections?
Lateral Nucleus
Describe the papez circuit
Hypothalamus -> Anterior Nucleus of the Thalamus -> Cingulate Cortex -> Hippocampus -> Mamillary Bodies -> Repeat
What is a central role of the Hypothalamus?
It judges the emotional salience of a cue and gives an output signal for emotional expression.
Which two subcortical networks are connected to the default mode network?
1) Hippocampal-Diencephalic Circuit
2) Temporo-Amygdala-Orbito-Frontal Network
What is sham-rage?
When certain connections or parts of the brain are removed, but the Hypothalamus stays intact, animals still show emotional behavior, which however is not motivated by rational cues.
What is the gist of James’ Peripheral Feedback Theory?
Feelings result from a set of physiological expressions
“First sweat, then anxiety”
Explain Cannon-Bard’s Central Theory of Emotions.
Emotions are processed by the brain:
Sensory Information -> Thalamus -> Hypothalamus & Cortex
- They first highlighted the importance of the hypothalamus in qualifying emotional cues
What is one deduction we can make from the papez circuit?
That emotional expression is under cortical influence.
What is a disease we can relate to the Papez circuit?
Korsakow Syndrome
What did MacLean come up with?
The visceral brain
- > building on findings of klüver-bucy and cannon-bard: Emotions are a product of the visceral brain
- > Was later redefined as the limbic system
Describe the LeDoux model of emotions
Kind of Dual Process theory:
High road: Thalamus -> Cortex -> Amygdala
Low road: Thalamus -> Amygdala
What is one of the main functions of the Amygdala?
Connecting external stimuli with emotional consequences
What is another name for a genuine smile?
Duchenne Smile
What were Duchenne’s findings in his 1862 experiment?
That many muscles around the eyes, involved in smiling are not easily controlled by free will.
What is a physiological difference between real and fake smiles?
Fake smiles are controlled by the motor cortex and the pyramidal tract, whereas Duchenne smiles are governed by the anterior cingulate gyrus and extrapyramidal pathways.
What is emotional facial paresis?
the ability to voluntarily produce facial expressions, but not when they are an involuntary reaction.
What do we call the disease, in which patients exhibit Duchenne smiles, but can’t produce fake smiles?
Voluntary Facial Paresis
What brain part is necessary for emotional conditioning?
Medial Geniculate Nucleus
What does HPA stand for?
Hypothalamic-Pituitary-Adrenal
What is the endocrine chain reaction in the HPA Axis?
Hypothalamus -> CRH -> Pituitary -> ACTH -> Adrenals -> Cortisol
Explain the Hippocampal cortisol regulation.
The hippocampus has cortisol receptors. If there is too much of it, the hippocampus inhibits the HPA Axis.
What is the Monoamine Hypothesis when it comes to the connection of the Limbic System and Affective Disorders?
Norepinephrine and Serotonin are Monoamines.
- Levels of these neurotransmitters predict mood.
