Flashcards in Limbic System Deck (55):
Where does the septal area project?
hypothalamus and brainstem & cingulate gyrus
Where does the cingulate gyrus receive input?
anterior nucleus of thalamus & septal area
What is the name for the anterior portion of the parahippocampal gyrus?
The entorhinal area, uncus and amygdala all share what function(s)?
olfactory & limbic functions
What nucleus is located immediately beneath the uncus?
Where do the mammillary bodies receive input?
Where do mammillary bodies project?
anterior nucleus of the thalamus
Fibres comprising the fornix arise from what structure
What nuclei are included in the septum pellucidum?
What connects septal area to the hypothalamus and brainstem?
medial forebrain bundle
What connects mammillary nuclei to the anterior thalamic nucleus?
How many cell layers in the hippocampal gyrus?
How many cell layers in the dentate gyrus?
What is the subiculum?
region of cortex at the top margin of the parahippocampal gyrus
immediately below dentate gyrus
What is the alveus?
collection of fibres covering surface of hippocampus
axons of neurons whose cell bodies are located in the subiculum and hippocampus
Describe the structures of the fornix and where they are derived
Alveus fibres covering surface of hippocampus aggregate as fimbriae of fornix --> crura -->body --> columns
Where is the hippocampus located?
floor of inferior horn of lateral ventricle
What type of cortex is the hippocampus?
What are the three layers of the hippocampus?
What type of cortex is the dentate gyrus?
What are the three layers of the dentate gyrus?
What comprises the hippocampal formation?
parahippocampal gyrus (subiculum)
What are two sources of axons leaving the hippocampal formation? (contribute to alveus)
What do the dentate granular cell projections contribute to?
local circuit connections within the hippocampal formation
What are the two divisions of the amygdala?
ventrolateral (basolateral) division
What division of the amygdala is associated with the limbic system?
ventrolateral (basolateral) division
What is associated with the dorsomedial division of the amygdala?
Where does CNI project directly to cortex?
dosomedial division of amygdala
Where does the septal region communicate?
True or False: The cingulate gyrus is continuous with the parahippocampal gyrus.
Where are the majority of fibres in the fornix derived from?
cells in the subiculum
Where do fibres of the fornix project to?
anterior thalamic nucleus
septal nuclei (precomissural bundle)
Where do fibres of the basolateral nucleus of the amygdala project to?
stria terminalis - projects to hypothalamus and septal nuclei
Where does the septal nucleus project?
hypothalamus & autonomic nuclei of stem & cord (medial forebrain bundle)
The mammillary bodies are reciprocally connected to to the anterior thalamic nucleus via what tract?
Where does the anterior thalamic nucleus project?
Where does the cingulate gyrus project?
association areas of frontal, parietal, temporal and possibly occipital cortex
parahippocampal gyrus (cingulum)
What procedure results in Kluver-Bucy syndrome?
bilateral temporal lobectomy
What are the S&S of Kluver-Bucy syndrome?
excessive sexual activity
inability to learn new tasks
impairment of ability to form new memories
What results from stimulation of the amygdala?
expression of fear and rage, arrest reaction (animals)
feelings of anxiety (humans)
What is Korsakoff's syndrome?
inability to form new memories
How does Korsakoff's syndrome occur? IN what conditions is it seen?
damage or degeneration particularly in mammillary bodies and dorsomedial thalamus
Aspects of limbic function related to emotional states are based on what structure?
Aspects of limbic function related to memory are based on what structure(s)?
What happened to HM when he had medial temporal lobe removed bilaterally?
unable to transfer short term to long term memory
spatial orientation compromised
DIAGRAM THE COMPONENTS AND CONNECTIONS OF THE LIMBIC SYSTEM
What is the difference between the source of input for fibres of the subiculum vs hippocampus?
subiculum - hypothalamus, septal nucleus, ATN
hippocampus - septal nucleus
Input from other cortical regions project to what layer of the neocortex
outer granular layer
input from thalamic relay nuclei project to what layer of the neocortex
inner granular layer
output from outer pyramidal layer of neocortex go to
other cortical regions
output from inner pyramidal layer of neocortex go to
brain & SC
What is the WADA test?
medical test to test for speech dominance
What are aphasias?
disruptions in speech
What are Betz cells?
large cells found ONLY in the primary motor cortex (precentral gyrus of frontal lobe)