Subcortical Structures Flashcards
Subcortical structures
Not visually identifiable; ID by observable bx; uncontrollable/involuntary motor movements (basal ganglia)
Basal Ganglia
Group of subcortical nuclei (caudate, globus pallidus, putamen, substantia nigra, subthalamic nucleus) located within the white matter in each cerebral hemisphere.
Important role in movement regulation; insult can lead to involuntary/uncontrollable motor movements, such as tremor, chorea, tics, ballism (not paralysis)
Seen in Parkinson’s, Huntington’s, Tourette’s, Wilson Disease, Sydenham chorea
caudate
C-shaped; pear-shaped head & long tail
Globus pallidus
AKA pallidum; wedge-shaped
putamen
half-moon shaped; caudal lateral to caudate & lateral to globus pallidus (pons, pallidus, putamen)
Lenticular Nucleus
Putamen & globus pallidus
Striatum
Putamen & caudate nucleus
Corpus Striatum
Putamen, globus pallidus, & subthalamic nucleus
diencephalon
subcortical nuclear masses that form the central core of the brain: Thalamus Hypothalamus Epithalamus Subthalamus
thalamus
two large, round structures (mostly gray matter) that lie on either side of the 3rd ventricle (almost the size of walnuts)
relays all sensory input (other than the olfactory) to cortex for conscious awareness
perception of crude aspects of pain, temperature and touch
impart pleasantness or noxiousness to sensation
hypothalamus
Location = floor of the third ventricle
Important for autonomic and endocrine functions
Helps to control emotional behaviors
Regulation of body temperature, hunger response, sexual and sleep behavior
Controls the pituitary gland = releases hormones
Epithalamus
Epithalamus = mainly the pineal gland; very small
-the pineal gland regulates the body’s circadian rhythms.
-regulates the distribution of hormones for reproductive systems
Subthalamus
houses nuclei whose fibers project in many areas (connector of sorts)Controls the pituitary gland = releases hormones
limbic system
Complex set of three C-shaped areas with gray/white matter:
Outer Arc
Middle Arc
Inner Arc
Function: emotion & motivation
- affects memory, learning, neuroendocrine levels, autonomic states; Highly interconnctd – insula, frontal lobes, brainstem
Autonomic states controlled by brainstem
Structural components:
- cingulate gyrus
- hippocampal formation
- parahippocampal gyrus
- uncus
- subcallosal gyrus
Collectively control memory, emotion, learning, fight/flight/fear autonomous systems
Limbic system affects regualtion of emotions, impulse control, controlling what we say (conn to frontal lobe – prb solve, thinking)
Indivs w/ addictions (drugs, food, sex) often related to limbic system; Hormonal changes – cravngs, mood swings- related to hyperstim of limbic system
Brain can learn ways to help regulate limbic system responses – pacing, deep breaths, etc
VPM = Ventral Posteromedial
-Relay for taste, temp, touch for head & face
