PS101 Lecture Notes - Lecture 10: Substantia Nigra, Locus Coeruleus, Reticular Formation
The Brain
● 3 major sections
1) Hindbrain - medulla, cerebellum, pons → old
2) Midbrain - reticular formation → relay system
3) Forebrain - subcortical and cortex (cerebral hemispheres) → new/thinking
The Hindbrain
● Medulla, cerebellum, pons
● Medulla (life sustaining functions)
○ Closest to the spinal cord
○ Controls vital bodily functions such as heartbeat, breathing, blood pressure,
circulation
○ Reflexes - coughing, swallowing (shared by midbrain too, because can be under
voluntary control)
● Cerebellum (everyday coordination)
○ Deep convolutions (densely packed)
○ Controls bodily balance and muscular coordination
○ Integrates information from muscles, tendons, and joints
● Pons
○ Functions as a relay mechanism
○ Assists in control of movement (swallowing, breathing, eyes, face)
○ Locus coeruleus - long axon, norepinephrine, attention/arousal (alertness)
● Hindbrain lower on the nervous system hierarchy
● Example of a transected cat → can stand if you hold him up, can’t move on his own, like
a marionette, doesn’t control his breathing etc
Hindbrain to Midbrain
● Contains neural centres (nuclei)
● Reticular formation (between hind and midbrain)
Midbrain
● Reticular formation regulates attention and alertness (sleep and arousal) → sometimes
involved in comas
● Midbrain contains neural centres that control some motor reactions/movement
● Substantia nigra - connect with forebrain
○ Neurotransmitter dopamine
○ Fluid movement, stopping movement
○ Parkinson’s
○ Athlete’s (not reflexive movement, coordinated practice movement)
Forebrain
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Document Summary
3 major sections: hindbrain - medulla, cerebellum, pons old, midbrain - reticular formation relay system, forebrain - subcortical and cortex (cerebral hemispheres) new/thinking. Controls vital bodily functions such as heartbeat, breathing, blood pressure, circulation. Reflexes - coughing, swallowing (shared by midbrain too, because can be under voluntary control) Assists in control of movement (swallowing, breathing, eyes, face) Locus coeruleus - long axon, norepinephrine, attention/arousal (alertness) Hindbrain lower on the nervous system hierarchy. Example of a transected cat can stand if you hold him up, can"t move on his own, like a marionette, doesn"t control his breathing etc. Reticular formation regulates attention and alertness (sleep and arousal) sometimes involved in comas. Midbrain contains neural centres that control some motor reactions/movement. Athlete"s (not reflexive movement, coordinated practice movement) Largest and most complex region: thalamus, hypothalamus, pituitary gland, limbic system, basal ganglia, cerebral cortex. Thalamus: relay system for all sensory information (except smell)
