Physiological Influences on Psychology, Part IThe Human ObserverSlide 3Real life exampleSlide 5Developments in Early PhysiologyResearch on Brain FunctionsSlide 8ExtirpationOther Approaches to Brain ResearchSlide 11From Outside of the BrainPhrenologySlide 14Slide 15Slide 16The Nervous SystemThe Mechanistic SpiritSo What Does All of This Mean?Discussion QuestionsSlide 21Slide 22FRIDAY, JANUARY 23RD 2015PHYSIOLOGICAL INFLUENCES ON PSYCHOLOGY, PART ITHE HUMAN OBSERVER•David Kinnebrook (1794) just couldn’t get it right in his astronomy lab, so he got fired•Years later, Friedrich Wilhelm Bessel examined the records of the lab and concluded that he wasn’t wrong – there were just individual differences among researchersTHE HUMAN OBSERVER•Thus, astronomers realized they needed to take into account subjective perception among individuals•Other sciences realized that differences in human observation could affect their research, too•Physiology began to study the sensory organs that contributed to these individual differences in perceptionREAL LIFE EXAMPLE•What color is this?REAL LIFE EXAMPLE•What color is this?DEVELOPMENTS IN EARLY PHYSIOLOGY•German physiologist Johannes Müller advocated the use of experimental methods in physiology during the 1830s•Published the Handbook of the Physiology of Mankind in 1833, an account of physiological research from the period•Proposed that each nerve is responsible for a specific sensation, which led to future research on the localization of physiological functionsRESEARCH ON BRAIN FUNCTIONS•Studying the localization of brain functions not only helped determine how the brain works, but also established sound methodology for the development of psychology•Marshall Hall (1790-1857), a Scottish physician, noticed that stimulating nerve endings in decapitated animals still caused movement•By doing this, he was able to identify which nerves contributed to which kinds of movementsRESEARCH ON BRAIN FUNCTIONS•Finding what happens when the brain is damaged is also important•This was the work of Pierre Flourens (1794-1867), a French professor who destroyed parts of the brain and spinal cord in pigeonsEXTIRPATION•Together, the work of these scientists demonstrates the extirpation method•Extirpation: a technique for determining the function of a given part of an animal’s brain by removing or destroying it and observing the resulting behavior changes•This happened kind of inadvertently with Phineas Gage•https://www.youtube.com/watch?v=9QXI_BxlY7MOTHER APPROACHES TO BRAIN RESEARCH•The clinical method: post-humous examination of brain structures to detect damaged areas assumed to be responsible for behavioral conditions that existed before the person died•Developed by Paul Broca (sound familiar?)•He found a lesion in the third frontal convolution in a man who could not speak intelligibly•This became Broca’s area!OTHER APPROACHES TO BRAIN RESEARCH•Um…–But between extirpation and the clinical method, you either have to have your brain damaged or die to figure out what’s going on with your brain…yikes–Many folks don’t enjoy having parts of their brain damaged for science while they’re still aliveFROM OUTSIDE OF THE BRAIN•Franz Josef Gall (1758–1828) dissected brains and confirmed the existence of white matter and gray matter•White matter: myelinated nerve fibers connecting the halves of the brain and the brain to the spinal cord•Gray matter: unmyelinated nerve fibersPHRENOLOGY•Gall moved to researching the shape of the head and what that revealed about a person–He realized that intelligent animals had larger brains–His study of craniology, later called phrenology, proposed that the shape of a person’s skull revealed his or her intellectual and emotional characteristics–He believed that bulges appeared for well-developed areas and indentations appeared for deficitsPHRENOLOGY•This fully ruined Gall’s reputation•However, a pair of European phrenologists traveled through Europe and the United States, giving lectures on phenology•Their writings inspired brothers Orson and Lorenzo Fowler to open a phrenology business, starting a huge craze of folks wanting their heads examined•It became so popular, that some businesses used phrenology to determine the best potential employees•Even a complex machine was created to best measure these bumps and indentations•http://www.youtube.com/watch?v=80dZ71Km6_gPHRENOLOGY•The research of Pierre Flourens’ (remember him?) using extirpation found that phrenology was basically hocum–The shape of the skull does not correspond to the shape of the brain–The mental functions attributed to certain areas also did not accurately correspond•Thus, phrenology was debunked, which wasn’t too good for psychology–Blame the Zeitgeist? Just because a view is popular doesn’t make it valid•Measuring the brain from the outside was deemed less effective than measuring it from the insideOTHER APPROACHES TO BRAIN RESEARCH•The electrical stimulation: a technique for exploring the cerebral cortex with weak electric current to observe motor responses•First promoted in 1870 by Gustav Fritsch and Eduard Hitzig•Electrical stimulation of certain areas of the brain leads to certain movementsTHE NERVOUS SYSTEM•By the mid-19th century, scientists accepted the electrical nature of nerve impulses•The central nervous system was described as kind of a grand central station for conducting these impulses•Anatomical structures of the central nervous system were also being discovered (neurons, synapses, etc.)THE MECHANISTIC SPIRIT•Still going strong in Germany in the 1840s•Scientists in the Berlin Physical Society still believed that all phenomena could be accounted for by the principles of physics•The discovery of nerve impulses and anatomical structures supported this ideaSO WHAT DOES ALL OF THIS MEAN?•British empiricists: all knowledge comes from sensation•Astronomy: the impact of individual differences•Physiologists: defined the structure and function of the human body, largely consistent with the mechanistic spirit•The next step was to experiment on the mindDISCUSSION QUESTIONS•What are some methods that scientist developed to map brain functions?DISCUSSION QUESTIONS•What was Gall’s craniology method, and how was it discredited?DISCUSSION QUESTIONS•Up until this point in the class, how do we see philosophical and physiological
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