Task 5 Flashcards
what does the limbic system contain of ?
- amygdala
-> emotional system - hippocampus
-> memory system - connection between
-> central limbic structures
-> olfactory system - mediational role between
-> cerebral cortex
-> brainstem motor control system
what is the allocortex?
- hig end side of the limbic system
- unus
-> rhinencephalon
-> connects the primary olafactory cortex with amydala & hippocampus - ictus
-> ventral part of the cingulate gyrus
what is the hypothalamus?
- low-end side of the limbic system
- interacts with the autonomic centres
-> responsible for instinctive behaviour - considered the top of the autonomous motor system hierarchy
- generates motivational states
what is the memory system?
circuit of papez
- FORNIX fibres are leaving the hippocampus
- can be traced to the mammarily bodies
- new fibre bundle goes anterior to the nucleus of the thalamus
-> via the cingulate cortex
-> to the HIPPOCAMPUS
What is the emotional system?
- starts in the caudal medial amygdala
- goes via the striaterminalis
- terminates in the
-> septal nuclei
-> hypothalamus
what is the amygdala?
- involved in the emotional system of the limbic system
- extended amygdala
-> caudal & medial nuclei
-> bed nucleus of the stria terminalis
-> main output
-> controls the generation of emotion
what is the rhiencephalon?
uncus
= medial part of the parahippocampal gyrus
= olfactory cortex
-> evolutionary olfactory cortex characterised objects as good and bad (by remembering their odors)
what is the striatum?
- ancient binding link between
-> olfaction
-> the fundamental autonomous action pattern
What is the connection to the Default Mode network?
- functional division
-> emotional system
-> memory system - hippocampal-diencephalic circuit
-> extends into cerebral cortex
-> via parahippocampal gyrus, ictus, Posterior cingulate gyrus
-> holds the first major hub of the DMN - temporo-amygdala-orbitofrontal network
-> leads to the anterior cingulate cortex
-> second major hub of the DMN
-> centred on amygdala and extends via orbito-insular cortex
what is limbic arousal?
- activation of sympathetic nervous system
- resistant to habituation
- gut feeling
- stimulation of the limbic midbrain areas (CGA & VTA)
-> motivational consequences - strong positive or negative effects
- hypothalamus
What is non-limbic arousal ?
- stimulating the ascending reticular activating system (ARAS)
- novel & unexpected stimulus
- can show habituation effects
- no motivational consequences
- brainstem
what is sham-rage?
- cat-rage behaviours without obvious target
- occurs when both cerebral hemispheres (= cortex, white matter, and basal ganglia) are removed from cats
- occurs as long as the caudal hypothalamus is intact
=> expression of coordinated emotional behaviours does not necessarily include cortical processes
What is the crucial difference between electrical stimulation at the level of brainstem and of hypothalamus?
- brain stimulation
-> some behaviour occurs - hypothalamus stimulation
-> induces motivation
-> if leasioned lethal lack of motivation
what is the central theory?
information about emotional stimulus
- via the hypothalamus & thalamus
-> evaluation of emotional wuality
- descending projections to brainstem & spinal cord
-> bodily response
- cortex
=> thalamocortical pathway = enables conscious feeling
what are networks that control the physiological expression of emotional states?
- endocrine system
= hormone release - autonomic motor system
= changes in physiological control systems - musculoskeletal system
= mediates overt behaviours
