Limbic System Flashcards
(52 cards)
Generally describe the limbic system:
The limbic system is a term used for a number of interconnected cortical regions and subcortical structures that function to serve a number of survival mechanisms.
List 5 cortical structures that are included in the Limbic lobe:
- septal area
- cingulate area
- parahippocampal gyrus
- hippocampus
- other related cortical areas (orbitofrontal cortex and prefrontal cortex)
Describe the septal area:
area surrounding end of rostrum of corpus callosum
What are the associated subcortical nuclei of the limbic system?
- amygdala
- hypothalamus
- septal nuclei
- anterior thalamic group
where is the amygdala located?
located deep to the uncus
Where is the septal nuclei located?
deep to septal cortical region; near the fornix and anterior commisure
List the 4 nerve fiber pathways of the limbic system:
- mamilothalamic tract
- fornix
- stria terminalis
- medial forebrain bundle
The limbic lobe connections are organized as a complex loop. The mamillary bodies connect to the ______________________ via the mamillothalamic tract.
anterior thalamic group
The anterior thalamic group connects to the __________________.
cingulate gyrus
the cingulate gyrus connects to the __________________________.
parahippocampal gyrus
the parahippocampal gyrus connects to the ________________________.
hippocamus
the hippocamus connects to the _______________________ and _______________________ via the ____________.
mamillary bodies
and septal region
via the fornix
Describe the route of the limbic lobe:
mamillary bodies –> anterior thalamic group (via mamilothalamic tract) –> cingulate gyrus –> cingulate gyrus –> parahippocampal gyrus –> hippocampus –> mamillary bodies AND sepatal region (via fornix)
How is the amygdala connected to the limbic circuit?
by way of the connections to the septal region and the hypothalamus via stria terminalis
What are the two afferents of the limbic system?
- cortex
2. reticular formation
In the limbic system, the afferent cortex projects:
to all parts of limbic lobe, amygdala and hypothalamus
In the limbic system, the afferent reticular formation projects:
to all parts of limbic lobe, amygdala and hypothalamus
In the limbic system list two of the efferent locations:
- limbic lobe
2. amygdala
In the limbic system the limbic lobe is efferent and projects to:
all parts of the cortex by way of thalamic gating
and to the hypothalamus and reticular formation
In the limbic system the amygdala is efferent and projects to:
dorsomedial thalamic nucleus, which in turn projects to prefrontal cortex (medial forebrain bundle)
in the limbic system the amygdala is efferent and projects to the brainstem reticular formation nuclei both directly and indirectly via the:
hypothalamus (medial forebrain bundle)
The limbic system generates behaviors necessary for:
preservation of the individual and the species (e.g., motivation, emotion, learning and memory).
In the limbic system, the relationship of anatomy to function is only partially known, but suffice it to say that the influence this system has on the hypothalamus and the autonomic nervous system is very powerful. Lesions of the hippocampus and amygdala must be ____________ to result in major deficits of normal behavior.
bilateral
In the limbic system, unilateral stimulation, however, may result in ____________ behavior.
abnormal