COGS 17 Lecture Notes - Lecture 2: Basal Ganglia, Cingulate Cortex, Olfactory Bulb
19 May 2018
School
Department
Course
Professor
Lec 1B - Anatomy of the Nervous System, cont.
● Diencephalon (in brainstem) of forebrain:
○ Thalamus
■ Projects to/receives from sensory, motor and arousal systems
■ Divided into many different nuclei. Each Nucleus - cluster of cells with
similar function
○ Hypothalamus
■ Below the thalamus
■ Interface of Neuroendocrine (brain and hormone) system → speaks to
phalagelar system
■ Divided into many different nuclei
■ Communicates to pituitary gland (the “master” gland)
■ Oversees feeding, fleeing, fighting, and sex, and temperature, clock
● Telencephalon: all other forebrain structures
○ Beyond the brainstem
○ Limbic system - motivation
■ Set of subcortical structures that form a border (or limbus) around the
brain stem
■ Thalamus not a part of limbic system
■ Hippocampus - memory (storing cognitive maps)
■ Amygdala (emotion - equally active when reading emotion on someone
else’s face. Social center)
■ Cingulate gyrus - +/- evaluator, a “re-entrant” system
● Functions as an evaluator, re-entrant - receives input from below
and re-enters system
■ Olfactory bulb
● Smell
● Basal ganglion
○ Organizing activity into tasks
○ Not really part of motor system, but more about learning
○ Another re-entrant system - motor information being composed by cerebellum,
moving through pons and up into thalamus - projected into basal ganglia before
moving up into higher cortical areas.
■ Higher cortical areas execute something, sends back info through basal
ganglia
■ E.g → routine of habits, subgoals
○ Parkinson's disease
■ Compromised connections from tegmentum to basal ganglia → motor
deficits
■ Progresses until fatal
● Basal Forebrain
find more resources at oneclass.com
find more resources at oneclass.com
○ Area of cortex that is next to hypothalamus and thalamus
○ Part of basic arousal system
○ ACh arouses cortex (acetylcholine)
○ GABA de-arouses cortex (inhibitory)
● Cerebral cortex
○ 6-layer sheet of cells, unfolded = 1 m square x 3 mm thick
■ Nissl stain for cell bodies
■ Weigert stain for fibers
■ Input or info projected to cortex enters at level 4
● Convoluted (folded) cortex
○ Each bulge is a gyrus
■ Many = “gyri”
○ Each fold is a sulcus
■ Many = “sulci”
○ Central sulcus
■ Deep sulcus that divides traditionally frontal lobe from parietal lobe
○ Lateral fissure
■ Very deep fold
■ Divides the temporal lobe from the upper regions
● 4 lobes of the cerebral cortex
○ Frontal lobe (dorsal anterior quadrant)
■ Primary motor cortex
● Voluntary action
■ Premotor cortex
● Prepare to act; planning
● Mirror cells
○ Simulation of observed action
■ Broca’s area
● Major language area of cerebral cortex
■ Prefrontal cortex
● Exercising self control, delayed gratification, planning, cultural
rules, etc.
● Orbitofrontal cortex
○ Evaluation behavior of self and other, ToM (theory of
mind), social strategy
○ Temporal lobe (side)
■ Audition
■ Medial face of temporal lobe: (a1) Primary projection area for audition,
from thalamus
■ Wernicke’s area - lateral side
● Specialized for speech recognition
■ Lower cortical areas - literal sensory input
■ Higher cortical areas - representations of sound becomes more abstract
■ Emotional expression and interpretation
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Lec 1b - anatomy of the nervous system, cont. Projects to/receives from sensory, motor and arousal systems. Each nucleus - cluster of cells with similar function. Interface of neuroendocrine (brain and hormone) system speaks to. Communicates to pituitary gland (the master gland) Oversees feeding, fleeing, fighting, and sex, and temperature, clock. Set of subcortical structures that form a border (or limbus) around the brain stem. Thalamus not a part of limbic system. Amygdala (emotion - equally active when reading emotion on someone else"s face. Cingulate gyrus - +/- evaluator, a re-entrant system. Functions as an evaluator, re-entrant - receives input from below and re-enters system. Not really part of motor system, but more about learning. Another re-entrant system - motor information being composed by cerebellum, moving through pons and up into thalamus - projected into basal ganglia before moving up into higher cortical areas. Higher cortical areas execute something, sends back info through basal ganglia.
