Lecture 13: The Limbic Brain Flashcards
Which structures are part of Broca’s “Limbic lobe”?
Cingulate cortex and hippocampus.
Where is the cingulate cortex located?
The cortex around the corpus callosum.
What function did Broca link the Limbic structures with?
He didn’t.
What function did Papez link the Limbic structures with?
Emotion.
Which structures are in “The Papez Circuit”?
Cingulate cortex Which projects to Hippocampus Which projects to Hypothalamus Which projects to Anterior nuclei of thalamus And back again.
What is the debate regarding the Papez circuit?
The structures are anatomically connected but there is debate whether they are functionally connected.
What is the name of the bundle of axons that project from the hippocampus to the hypothalamus?
The fornix.
What are the 6 brain structures associated with the Limbic Brain?
Cingulate cortex Hippocampus Amygdala Hypothalamus Insula Nucleus Accumbens
Can Harry Actually Hide Inside Nagini
Other than Phineas Gage, what is another real life scenario that implicated the Limbic system with emotion?
The frontal lobotomy. Resulted in blunting if emotional responses and loss of emotional component of thoughts.
What is Kluver-Bucy syndrome?
Caused by damage to the temporal lobes, particularly the amygdala, the condition results in an absence of emotional responses (fear, rage and aggression cease to exist), hypersexuality, visual agnosia and a compulsion to be overly attentive. First seen in monkeys after removal of temporal lobes, same symptoms also in humans.
The human amygdala is a complex of what?
Nuclei.
Which part of the amygdala receives inputs from many sensory circuits?
The basolateral nuclei.
Do outputs from the amygdala reach the thalamus or the hypothalamus?
Both. And more structures.
If there is a lesion in the amygdala, is the ability to recognise fear in facial expressions or in voices lost?
Cannot recognise fear in facial expressions but can recognise fear in voices.
What are the stages of the process that occurs when conditioning the amygdala to associate a sound with pain?
- Auditory and somatosensory cortices send signals to the basolateral nuclei of the amygdala
- Signals are then sent to central nucleus of the amygdala
- Efferents from the central nucleus go to the hypothalamus (resulting in autonomic response), to the Periaqueductal gray matter in the brain stem (resulting in behavioural response) and to the cerebral cortex (resulting in an unpleasant emotional experience).
What is the function of the circuit loops that connect the cerebellum and basal ganglia with the limbic brain?
To modulate motivation and drive-related behaviours.
Pleasurable experiences are preceded by increased release of what neurotransmitter in the ventral striatum?
Dopamine.
The cingulate cortex of the limbic brain forms a loop with which part of the cerebellum?
Vermis.
Which structure in the brain is associated with homeostasis, reproduction and emotional behaviours?
The hypothalamus.
How does the hypothalamus control hormone production?
Via the pituitary gland.
Which lobes do you have to peel back to be able to see the insula?
The frontal and temporal lobes.
Is the anterior or posterior insula a cortical centre for pain?
The anterior insula.
What is the central insula associated with?
Language.
What does the posterior insula perhaps play a role in? Why?
Might play a role in pain evaluation because it is connected to the amygdala.
