Biological Psychology and Brain Function

Franz Josef Gall: 19th-century German physician and founder of phrenology.
Phrenology: The theory that personality and character traits are linked to skull morphology (bumps and ridges).
Localization of Function: The scientifically correct concept that specific parts of the brain control specific behaviors and functions (e.g., vision, memory, facial recognition).

Central Nervous System (CNS): The body's command center and primary decision-maker.
Peripheral Nervous System: Consists of sensory neurons that gather information and report it to the CNS.

Incident (1848): A railroad explosion sent an iron rod through Gage's left cheek and the top of his head.
Physiological Impact: Gage survived, remained conscious, and regained physical health, though a "teacup full" of brain was lost.
Psychological Impact: His personality shifted from mild-mannered to surly and vulgar; observers noted he was "no longer Gage."
Significance: Provided early evidence that physical brain damage can fundamentally alter personality and the mind.

10% Myth: The idea that humans use only 10% of their brains is false; nearly every region is active during simple tasks.
Energy Consumption: The brain requires 20% of the body's total energy.

Brainstem: The most ancient core where the spinal cord enters the skull.
Medulla: Controls automatic functions like heart rate and breathing.
Pons: Helps coordinate movement.
Thalamus: Hub for sensory information (seeing, hearing, touching, tasting).
Reticular Formation: Nerve network inside the brainstem essential for arousal (sleep, walking, pain perception).
Cerebellum: The "little brain" responsible for nonverbal learning, memory, and voluntary movement; easily impaired by alcohol.

Amygdala: Two clusters of neurons responsible for memory consolidation, fear, and aggression.
Hypothalamus: Regulates body temperature, circadian rhythms, hunger, the endocrine system (via the pituitary gland), and pleasure/reward.
Hippocampus: Central to learning and processing new facts and memories.

Cerebrum: Comprising 85% of brain weight; divided into two hemispheres connected by the corpus callosum.
Cerebral Cortex: A thin layer of 20,000,000,000 interconnected neurons covering the hemispheres.
Glial Cells: Billions of non-neuron cells that provide support, insulation, and nourishment to neurons.

Frontal Lobes: Involved in speaking, planning, judging, abstract thinking, and personality.
Parietal Lobes: Process sense of touch and body position.
Occipital Lobes: Process visual information.
Temporal Lobes: Process sound and speech comprehension.
Motor Cortex: Located at the rear of the frontal lobes; controls voluntary movements.
Sensory Cortex: Processes incoming sensations.
Association Areas: Regions involved in higher mental functions like thinking, learning, and linking sensory input with memory.