Limbic Systems 1 Flashcards
(19 cards)
Give an overview of the anatomy of the limbic system: cortical regions
prefontal
cingulate
insula
parahippocampal gyrus
Give an overview of the anatomy of the limbic system: subcortical regions
hippocampus
basal ganglia
amygdala
Describe the neurological pathways using: norepinepherine
projects from LOCUS CERULEUS in pons to cortex
additional selectivity under stress
Describe the neurological pathways using: dopamine
projects from VENTRAL TEGMENTUM in midbrain to PFC and basal ganglia
PFC projection promotes motivationally based behavior
Describe the neurological pathways using: serotonin
RAPHE NUCLEUS to extensive cortical areas
mood, sleep/wake cycles
Describe the neurological pathways using: acetyl choline
septum, nucleus basalis, and diagonal band of Bronca project to thalamus and extensive cortical areas
Where is the hippocampus located?
near the medial temporal lobe surface
bulges into lateral ventricle
Describe the connections of the hippocampus
sensory, assaciation, cingulate, and prefrontal cortex
What are the functions of the hippocampus?
declarative/episodic memory
- mediates the recording of episodic memories
- Identifies common features between episodes
- Links these common episodes in a memory space
What is declarative memory
memories which can be consciously recalled, facts/knowledge
Distinguish between episodic and semantic memory
Episodic- specific autobiographical memories or events, auto-noetic
Semantic- non-contextual content of experience or knowledge about the world, noetic consciousness
Describe the rold or the hippocampus and vmPFC in forming and consolodating declarative memory.
Hippocampus encodes and consolidates episodic moments and projects them to wide areas of cortex (semantic facts)
PFC- working memory/short term
Describe the stages of sleep and their EEG correlates.
Non-REM- 4 stages- EEG waves increase in amplitude and decrease in frequency
SWS in last stages of Non-REM
REM- EEG is similar to waking: low amplitude and high frequency
What are the pathways that maintain wakefulness, and how do you fall asleep?
Thalamus- active during waking and REM, inactive during non-REM
Cholinergic pathway
Cortex- processes input from thalamus, monoaminergiv pathway (NE, 5HT, DA)
How is sleep regulated by a circadian cycle?
SCN(suprachiasmatic nucleus) responds to light/dark
Projects to:SPZ (supraventricular zone)
DMH (dorsal medial nuclei of hypothalamus)
When does reactivation of memory occur during sleep?
SWS
When are memories consolidated?
SWS, consolidation of declarative and procedural memory
REM- final consolidation
What role does the septum and diagonal band of Bronca have in memory consolidation during sleep?
Ach regulates activation of memory traces in hippocampus
Waking- increased Ach, increased sensory inpu and encoding in hippocampus
SWS, decreased Ach, increased reactivation of memories in hippocampus and their transfer to neocortex
How is memory consolidation affected in Alzheimers disease?
degeneration of cortex, cholinergic, and other neuromodulatory tracts
inability to consonlidate short term to long term
