The Limbic System Flashcards
What is the simple role of the limbic system?
Regulates our emotional and behavioural responses, particularly responses needed for survival
The five F’s of the limbic system: Feeding, fighting, fleeing, feeling and ‘romance’
Give a rough idea of where the limbic system is created.
The initial cortical regions around the brainstem.
Is deep within the brain, above the brainstem and below the cerebral cortex.
What did Charles Darwin note about emotion?
That emotion is similar between different species and humans of different cultures and populations.
This suggests that primary emotion has an evolutionary basis.
What did Paul Broca argue about the limbic system?
Believed the limbic system was mainly olfactory and that our sense of smell had a crucial impact on how we generate and regulate emotions.
The included the oflactory bulb, tract and tubercule in the limbic system.
What is important to note about the location of the olfactory areas of the brain?
Are in close proximity to the amygalda, is likley due to olfactory strong ifluence over primitive emotions is mammalian groups.
What are the different anatomical regions of the olfactory system and what is there function?
The olfactory bulb - deep to the cribiform plate, receptor neurone from the olfactory epithelium synpase with olfactory bulb neurones (formation of the cranial nerve)
The olfactory tract - connects bulb to cortex
The optic tubercule - role in motor guided motivational behaviour
The piriform cortex - processes and codes olfactory information (decides what you are smelling - good/bad)
The entorhinal cortex - links normal odor perception and memory.
What is the role of the optic chiasm?
Allows afferent information from the optic nerve to cross the the contrlateral side.
What is the histological classification of the pyriform cortex (part of the olfactory system)?
Paleocortex
Made of three distinct layers, this is a more ancient style of organisation.
What is the histological classification of the primary motor and visual cortex?
Neocortex
Six histological layers
This is the dominant type of histology associated with higher cognitive function
What is the histological classification of the hippocampus?
The archicortex
What is the role of the hypothalamus?
How does this link to sham rage?
Controls the ANS
Role in emotion
When the hypothalamus is lesioned sham rage occurs.
What is the Papez circuit?
Why is it important in the development of the limbic system?
First person to suggest the limbic system (extras such as hypothalamus alongside the olfactory system) were involved in emotional control based on anatomical circuit tracing and patients with lesions
The papez circuit is:
1. Hippocampus
2. Fornix
3. Mammillary bodies (posterior hypothalamus)
4. Mammillothalamic tract
5. Anterior thalamic nucleus
6. Cingulate cortex
7. Hippocampus
Harry Found Megan, Megan Agitated Catherine Horribly.
What are the different functions of the hypothalamus, hippocampus and the thalamus?
All are componenets of the limbic system
The hypothalamus - regulates the ANS and emotion (causes sham rage)
The hippocampus - also has a role in memory
The thalamus - relays motor and sensory information to cortex
What is the cingulate cortex?
Located just above the corpus callosum.
Part of the limbic system, links emotions, reward and punishment system to behavioural outputs, links limbic system to the rest of the cortex.
What is the corpus callosum?
White matter that links the two cerebral hemispheres of the brain.
What are the different roles of the neocortex, cingulate cortex and the hypothalamus in emotion?
Neocortex - emotional colouring, thoughts and ideas associated with emotion, blue =sad
Cingulate cortex - emotional experience - what we determine the emotion as
Hypothalamus - physical response through the ANS, increase HR etc
Give the basic location of the amygalda.
Is located within the medial temporal lobe, just anterior to the hippocampus.
Bilateral structure.
What is the function of the amygdala?
Is associated with anger, violence, fear and anxiety
What might suppression or removal of the amygdala cause?
Unable to recognise or conceptualise fear
Mellowing on personality.
Kluver-Bucy disease - hyperorality, hypersexuality, disinhibited behaviour, describe as having no fear of consequences.
Describe the location of the hippocampus.
Is located in the medial temporal lobe, just posterior to the amygdala, loops round as the fornix posterior then superior to the thalamus to become the mammillary bodies posterior to the thalamus.