6. The History of Biopsychology Flashcards
Egypt, 1700 BC
Egyptians did not think that the brain was an important organ; they believed the mind was located in the heart
Edwin Smith surgical papyrus
First written account of the brain, its anatomy, the meninges, and CSF
Described how the site of the head injury was related to neurological symptoms
Ionian philosophy
Greece, 600 BC
Set of laws by which the universe is governed, we can understand those laws by reason
Alcmaeon of Croton
Greece, 500 BC
Early dissection experiments
First philosopher to champion the idea that the brain was the seat of the mind
Hippocrates
Greece, 460-370 BC
First to believe that diseases were due to natural causes
Attempted to separate medicine from religion
Also believed the brain is the seat of the mind
Plato
Greece, 427-347 BC
Believed brain was the seat of the mind
Argues against science in general– believed in use of reason over observation and experimentation
Advocated for ideal forms over actual objects
Statues > dissections
We should only focus on the ideal form
Plato’s concept of the soul
Tripartite soul
Tripartite soul
Immortal soul (rational): head
Superior mortal soul (spirited): heart
Inferior mortal soul (appetitive): liver/gut
Aristotle
Greece, 384-322 BC
Believed the mind was located in the heart
Saw the brain as a “radiator” for the rest of the body
Capillaries carry blood to the brain to disperse heat
Greeks and dissections
Greeks had respect for the human body– dissections illegal
Limited their progress in understanding physiology
Musaeum at Alexandria
Compared to modern-day NIH
Scholars who worked together to create extensive library of science
Herophilos
First to distinguish between cerebrum and cerebellum
Described the meninges, sinuses, and ventricles
Believed all nerves originated in the brain and traced pathways to sensory and muscle organs
First to distinguish between sensory and motor nerves
Erasistratus
Believed that the number of convolutions in the brain was correlated with intelligence
Psychic “pneuma” (CSF) entered the brain through hollow sensory nerves
Galen
Greece, 130-200 AD
Performed dissections
Promoted humoural theory
Believed mental diseases could be attributed to the obstruction of “pneuma” by one of the four humours (or due to the excess of a particular humor)
Humoural theory
Idea was that disease was caused by imbalances of the four humours: black bile, yellow bile, phlegm, and blood
Medeival Europe, 200-1500 AD
Humoural theory remained prominent
Church was concerned with the non-material nature of the soul
They thought mental faculties were located within the ventricles
“The Ventricles”
Anterior ventricle: sensation
Middle ventricle: cognition
Posterior ventricle: memory
Europe, 16th century
Galen’s works translated to Arabic
Vesalius: founder of modern human anatomy
Age of Enlightenment
“Age of Reason”
Resurgence of scientific study and interest in understanding the mind and brain
Descartes
Netherlands, 17th century
Proposed a modified version of pneumatic theory
Nerves contain “animal spirits,” which are responsible for the flow of sensory and motor info in the body
External stimuli pull on threads to open gates in the ventricles, which allow for the flow of pneuma through the rest of the body
Cartesian Dualism
Netherlands, 17th century
The mind and body are separate but able to interact (via the pineal gland)
Darwin in The Galapagos
Noticed differences in beaks of finches based on environment
Inspired his theory of natural selection
Four Principles of Natural Selection
More individuals are born in each generation than can survive
Phenotypic variation exists among individuals, and this variation is inherited
Those individuals with heritable traits that are better suited to their environment will survive
New species form due to reproductive isolation
Robert Hooke
First microscope
First to coin the term cell
Johann Purkinje
First used microtome (allowed him to make really thin slices of tissue for microscopic study)
1837: discovery of Purkinje cells
Camillo Golgi (1873, Italy)
Golgi staining method
Reticular Theory: the nervous system is made up of one continuous web-like network
Santiago Ramon y Cajal
Used the Golgi method to study neuron structure
Showed that neurons were not interconnected and had distinct structures
Created Neuron Doctrine
Luigi Galvani (1780)
Frog leg muscles twitch when struck by an electric spark
The legs have to be creating electrical charge by chemical process
Alessandro Volta (~1800)
Rejected “animal electricity”
Thought result was a phenomenon produced by the wires themselves
Frederick von Humboldt
Galvani and Volta are both right
Emil du Bois-Reymond
Differentiated nerve and muscle current
Julius Bernstein
Student of du Bois-Reymond
Developed earliest modern membrane theory of an action potential
JZ Young (1938)
Discovery of giant squid axon
Nerve fibers conduct action potentials
Enables study of excitable membranes
Hodgkin & Huxley (1952)
Mathematical model to explain how action potentials propagate based on characteristics of a cell
Why is there scientific controversy?
Data isn’t always perfect
Localization of function
Definition: certain parts of the brain are allocated to certain functions
Albrecht von Haller (1752)
Published work distinguishing between grey matter and white matter
Thought that white matter represented the seat of sensations
Reintroduced idea of localization of function
Phrenology (knowledge of the mind)
Study of shape and size of head as indication of personality and mental abilities
Introduced by Gall
Brain separated into 35 distinct organs that have specific functions
“Reading someone’s head” by its shape
Pierre Flourens (1825)
Asked to verify Gall’s claims
Developed techniques to selectively lesion parts of brain
Concluded there’s no localization of function, brain acts as one unit
Jean Baptiste Bouillaud (1823)
Localized higher intellectual facilities to frontal lobe
Pierre Paul Broca (1861)
The Case of Tan
Broca’s area
Carl Wernicke (1874)
Not all language deficits are allocated to Broca’s area
Wernicke’s area
Karl Lashley (1944)
Trained rats to run mazes, ablated different parts of the brain
Found that memory deficits based on size of leison rather than location
Wilder Penfield (1950s)
Neurosurgeon with interest in treating epilepsy
Found that stimulation of temporal lobes could lead to vivid recall of memories
