Overview
This lecture covers major brain regions, their basic functions in behavior and mental processes, hemispheric specialization, and disorders linked to brain area damage.
Brainstem and "Older" Brain Structures
- The brainstem is the oldest brain part, responsible for automatic survival functions.
- Medulla controls autonomic functions like heartbeat, breathing, circulation, and reflexes.
- Pons regulates sleep, arousal, and movement; connects the brainstem with the cerebellum.
- Thalamus acts as a sensory relay station, directing most sensory input (except smell) to appropriate cortical areas.
- Reticular formation regulates arousal, sleep-wake cycles, and pain perception.
- Cerebellum coordinates movement, balance, and integrates sensory information about body position.
Limbic System and Midbrain Structures
- The limbic system is a network including the amygdala, hypothalamus, hippocampus, and pituitary gland.
- Amygdala processes basic emotions, especially fear and anger; damage can eliminate fear responses.
- Hypothalamus regulates hunger, thirst, body temperature, emotion, and controls the endocrine system (pituitary gland); responsible for the "four F's": fight, flight, feeding, and fornication.
- Hippocampus is crucial for forming and retrieving memories, especially converting short-term to long-term memory.
The Cerebral Cortex and Lobes
- The cortex is the brain's outer layer, responsible for higher-order processing and complex integration.
- Occipital lobe (back of head): processes visual information.
- Parietal lobe (top/rear): processes touch, integrates body position and movement.
- Temporal lobe (sides): processes auditory information and language comprehension.
- Frontal lobe (front): controls muscle movement, planning, attention, organization, and personality; prefrontal cortex supports empathy and impulse control.
Language and Specialization
- Broca's area (left frontal): speech production; damage causes expressive aphasia.
- Wernicke's area (left temporal): language comprehension; damage causes receptive aphasia.
Hemispheric Specialization and Corpus Callosum
- The corpus callosum connects the left and right brain hemispheres for integrated functioning.
- Split-brain surgery (severed corpus callosum) used to treat severe epilepsy, can cause "two brains" phenomena.
- The left hemisphere: specializes in language, logic, reading, writing, and math.
- The right hemisphere: specializes in spatial processing, facial recognition, patterns, and emotional expression.
Key Terms & Definitions
- Brainstem — oldest brain area for survival functions.
- Medulla — controls heartbeat and breathing.
- Pons — regulates sleep, arousal, and movement.
- Thalamus — sensory relay station (except smell).
- Reticular Formation — regulates arousal and pain perception.
- Cerebellum — coordinates movement and balance.
- Limbic System — network for emotion and memory.
- Amygdala — processes fear and anger.
- Hypothalamus — regulates basic drives and endocrine system.
- Hippocampus — forms and retrieves memories.
- Cerebral Cortex — outer brain layer for complex thought.
- Broca's Area — speech production.
- Wernicke's Area — language comprehension.
- Corpus Callosum — connects brain hemispheres.
- Aphasia — language impairment due to brain damage.
Action Items / Next Steps
- Watch the split-brain video on Canvas.
- Try the Stroop test for hemispheric specialization.
- Complete discussion assignments and quizzes.