Lesson 4 - Physiology and Psychophysics Flashcards
What is the main finding of Franz Joseph Gall? When did he start his observations?
Childhood findings: his classmates who had large, bulging eyes were able to memorize verbal material
Adult Neuroanatomist Ambition: he found modularity and localization of brain functions
• Developed the 1st cohesive ideas about phrenology (empirically discovered)
How was phrenology first called?
• At first it was named Organology because it studied the organs of the brain
What technique did Gall use to decipher the magnitude of one’s faculties?
Used cranioscopy to decipher the magnitude of one’s faculties
• Carnioscopy: Faculties of the mind (acting upon and transforming information) are not equally developed among all people
• Well-developed: bump
• Underdeveloped: indent on skull
How many organs did the brain have according to Gall? How many were shared with other species?
Suggested that the brain was separated in 27 separate organs, each responsible for different functions of the mind
• 19 were shared with other species
• 8 were specific to humans
What was the work of Johann Gaspar Spurzheim about?
Saw organology as an opportunity to advance his career
Parted ways with Gall in 1813, and he developed phrenology
• Spurzheim became a popular writer and lecturer
• The public was interested in phrenology
• Mental muscle approach: if you are lacking in one area you can train it
Will be less and less scientifically proven, as more research will suggest that they were not correct
Who made a show from phrenology? How?
The Psychograph was patented in 1905 by Henry Lavery and was used in department stores and theatre lobbies during the great depression
• Measured skull size and indicated the person’s personality in 5 mins
How was phrenology introduced to the USA?
Came for the first time in the USA in 1820, with a lecture by John Collins Warren to the Massachusetts Medical Society Americans were interested in: • What works • What helps What is practical
Who made a business out of phrenology?
The Fowler brothers developped a successful business
• Provided phrenological consultations
• Sold busts for 1$ each
Summarize the work of Pierre Flourens about phrenology
Attempted to scientifically disprove phrenology in 1815
• Using Ablation/Extirpation (destroying parts of the brain to see the behavioural consequences resulting)
• Investigated localized functions in the brain
His findings were contrary to the phrenologists
Observations:
• Much of the brain works as a single unit
• The function that was lost to an ablation could be regained later in most cases
• Challenged Gall’s view that personality could be attributed to the size/shape of the brain
• Behaviours could be tested but not personality
• Never really saw different brain sizes, and if there were there was no incidence on the brain’s function
• Indents on the skull did not influence functions unless it was due to an accident
Describe the results of Flourens’ ablation studies
Ablation studies: Experiments with pigeons • Vestibular system removed impaired • Sense of balance • Spatial orientation • Coordinating movement with balance • Cerebellum removed • Muscular coordination • Sense of equilibrium • Medulla oblongata • Death of the animal • Mid Brain • Visual and auditory reflexes
Describe Paul Broca’s work with “Tan”
French Physician treating a man who was only capable of saying “Tan”
• Dissected his brain and found a lesion in the left hemisphere caused by neurosyphilis
Flourens was not entirely correct either
Clinical method:
• Observe someone with a brain disorder (since we cannot dissect live humans)
• Posthumous examination of brain structures allowed to detect damaged areas assumed to be responsible for the behavioural conditions that existed before the person died
What is Broca’s area?
Broca’s area
Region responsible for speech production
• Lesion: Broca’s aphasia
• Understands speech, but unable to respond intelligibly
What is craniometry? Who invented it?
Craniometry: determine the relationship between brain size and intelligence
• Larger = more intelligent
• Indicated that men are + intelligent than women
Paul Broca
What is Wernicke’s area?
Wernicke’s Area (10 yrs later)
Similar problem to Broca’s aphasia
• People were able to speak, but not to comprehend language
• Wernicke’s aphasia
Describe Phineas Gage’s case and what it allowed researchers to discover
Broca and Wernicke showed that although there is localization of function in certain regions, there is also some distribution
• A railroad accident will give researchers insight into the role of the frontal lobe and its connection with emotion and personality
• Phineas Gage was a foreman working on a railroad
• Iron rod exploded through his skull (left side)
• Survived but began acting differently
• Used profanity
• Unable to maintain a job or a relationship
• Difficult time making and following plans
• Became irritable
• Damage of the frontal lobe: specifically responsible for executive functioning (planning, emotional regulation, delaying gratification)
Describe Eduard Hitzig’s experiments with soldiers
Danish-Prussian war of 1863
• Eduard Hitzig worked with soldiers wounded in battle
• Soldiers had parts of their skull removed with exposed brain visible
• Applied wires from a battery to the cortex
• Observed involuntary reactions, twitching and screaming
Describe Gustave Fritsch’s work with Hitzig
In 1870 Gustave Fritsch joined Hitzig
They removed part of live dogs’ skulls to expose the cortex
• Electrical stimulation of the cortex revealed that:
• The cortex is not insensitive
• Muscular movements on the opposite side of the body are elicited, thus discovering the motor cortex and contra-laterality
• What would turn out later to be the sensory cortex was also discovered
Describe the work of David Ferrier, following Fritsch and Hitzig’s steps
David Ferrier (1843-1928)
Used similar methodology as Fristch and Hitzig
• Used non-human primates to produce a more articulate map of the cortex
• Able to provoke:
• Movement of one finger
• Twitch of an eyelid
What aspect of Descartes’ reflex action theory will be re-evaluated?
Descartes believed that bodies worked like machines and that the nerves were hollow tubes
• This perspective will be re-evaluated
• Is there no directionality/specificity?
Describe David Hartley’s work regarding associationism
Physician, became known as the father of associationism
Influenced by: Locke and Newton
• Mind/body connection contended that a physiological response was needed to engage the physical mind
• Synthesized Newton’s conception of nerve transmission (which stated that nerves were activated with vibration) with versions of empiricism
• Nerves are solid, not hollow
• When a vibration starts in the nerves, the law of inertia maintains it
• Nerve vibration was also responsible for the experience of pleasure and pain (hedonistic)
• Excessive vibration = pain, mild = pleasure
• Suggests that the law of association (associating actions with pleasure and pain) can be applied to behaviour to describe how involuntary behaviour can lead to voluntary behaviour
