lecture 1 introns
Trepanation
Prehistoric cranial surgery removing part of the skull; bone regrowth shows patients survived, suggesting early recognition that the brain had medical importance
Ancient Egyptians — view of brain vs heart
Believed the heart was the center of intelligence and emotion; preserved organs carefully after death but removed the brain with a hook and discarded it
Alcmaeon (Ancient Greek philosopher)
First known thinker to argue the brain is the seat of intelligence; used empirical observation and anatomical dissection; traced nerves back to a single point at the brain, shifting focus from heart to brain
Hippocrates
Proposed brain was responsible for thought, sensation, and behavior; supported brain-centered view of mind
Aristotle
Rejected brain importance; believed heart controlled intelligence and emotion and brain functioned mainly for cooling blood
Galen
Physician to gladiators; studied brain injuries and animal dissections; demonstrated cutting nerves eliminated specific functions; concluded mind is located in the brain
Galen — animal spirits theory
Believed “animal spirits” flowed through brain ventricles to control movement and sensation; natural spirit located in liver
Andreas Vesalius
One of first scientists to dissect human bodies; showed animal anatomy does not perfectly match humans; published De humani corporis fabrica with accurate brain illustrations; demonstrated nerves originate from brain rather than carrying spirits
Thomas Willis
Considered father of neurology; proposed brain consists of specialized structures with different functions rather than a single unified organ
René Descartes — dualism
Proposed mind and brain are separate entities (mind–body dualism); body operates mechanically; reflexes explain stimulus–response behavior
Descartes — pineal gland theory
Believed pineal gland was interaction point between mind and body; mechanism incorrect but introduced reflex concept
Luigi Galvani — animal electricity
Showed electrical stimulation caused movement in dissected frogs; touching nerve caused strong movement, tissue caused weaker movement; concluded electricity exists in biological tissue
Emil du Bois-Reymond
Used galvanometer to measure electrical current between nerve and muscle; demonstrated nerves transmit electrical signals
Phrenology
Study of skull bumps to infer personality traits; scientifically incorrect but introduced idea that mental functions are localized to specific brain regions
Franz Joseph Gall
Founder of phrenology; proposed different psychological functions reside in distinct brain areas; concept of localization later supported by lesion studies
Phineas Gage
Railroad worker injured when metal rod passed through frontal lobe; survived but personality changed dramatically (more impulsive and argumentative); demonstrated frontal lobe role in personality and behavior
Paul Broca
Studied patients with speech production deficits; found consistent lesion in left frontal lobe (Broca’s area); evidence for language localization
Broca’s area
Left frontal brain region necessary for speech production
John Hughlings Jackson
Studied motor epilepsy; observed predictable movement progression during seizures; contributed to mapping body representation in motor cortex
Somatotopic organization
Body represented in organized map across motor cortex (idea supported by Jackson’s observations)
Wilder Penfield
Neurosurgeon who electrically stimulated cortex during epilepsy surgery; patients reported sensations or movements; created functional maps of sensory and motor cortex
Brodmann
Divided cerebral cortex into numbered regions based on cellular structure; Brodmann areas linked anatomy with function
Purkinje
Described large branching neurons in cerebellum (Purkinje cells); advanced microscopic study of brain structure
Purkinje cells
Large cerebellar neurons important for motor coordination
Camillo Golgi
Developed silver nitrate/potassium dichromate stain that made entire neurons visible (Golgi stain)
Golgi stain
Randomly stains small number of neurons completely black, allowing full visualization of neuron structure
Santiago Ramón y Cajal
Used Golgi staining to map neural circuits; concluded brain composed of individual cells communicating at connections
Neuron doctrine
Brain made of discrete neurons connected by synapses, not a continuous network
Synapse
Junction where neurons communicate with one another