TOPIC 1: The history and philosophical foundations of Psychology

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1 TOPIC 1: The history and philosophical foundations of Psychology What is history? Many kinds of psychology - more than clinical Scientific study of mental processes, brain and behaviour and the relationships between them - the brain is a complex network Reasons to study Psychology Approaches - biological, individual, social Why study history? Psychology - the scientific study of the brain, mental processes and behaviour and the relationships between them Brain - neuro-biological processes that generate mental processes Mind - individual sensations, perceptions, thoughts, emotions (subjective) Behaviour - actions that can be observed Many kinds of psychology Biological Developmental Social Economic Clinical About general rules not individual cases Discover the principles of the mind, brain and behaviour understand problematic cases Individual cases understand general principles Gain insights into... Mental states experiments, observations Role of genes and environment twin studies, nature vs. nurture Brain in action neuro-imaging, electrophysiological measurements Reasons to study it Describe behavior Understand and explain behaviour Predict future behavior Control/influence behaviour History The history of psychology is a consensus between scientists we believe are smart and trustworthy Presentist bias - analysing historic events using modern perspectives/ideas To study history effectively we must forget the past History is based on people s interpretation, given their frame of reference Western bias - analysing historical events through our own cultural lens Confirmation bias - only paying attention to facts which support our ideas Zeitgeist - general trend of thought or feeling characteristic of a particular period of time Brain functions and cerebral specialisation 1

2 History has different perspectives - some may be ignored Zeitgeist is important Wilhelm Wundt s lab in Leipzig Trepanation and what it might tell us about the brain Alhazen Born 965, Iraq Edwin Smith Papyrus Brain vs. soul 3 cell doctrine Localisation in the brain Phrenology Lesion studies on animals Phineas Gage Lobotomy Broca and Tan Werniki Do we need a brain? - plasticity Modern day phrenology? A network The history of psychology Incas in Peru BC Trepanation - hole drilled in skull release pressure/demons from brain Ancient Egypt BC Heart was the seat of the soul Feelings and thinking from heart not brain During mummification Heart stayed in body Brain discarded Treatment of organs importance The Edwin Smith Papyrus Ancient Egyptian medical text Believed to be written by Imhotep About the head wounds of soldiers Brain lesions distal symptoms Left side of brain controls right side of body and vice versa Brain responsible for speech Touching brain epileptic seizure Specific functions are localised in the brain Cerebral localisation - thinking in terms of localised functions 2

3 Herophilus of Chalcedon BC Described the ventricles Ventricle - fluid filled open structure (4th discovered later) 3 cell theory 3 cell doctrine Drawing by da Vinci Cell 1 - info from senses Cell 2 - cognition/thinking Cell 3 - memory Wilhelm Wundt s Established 1st psychological lab - Leipzig, Germany Start of scientific psychology Wanted to know how our mind/brain works Franz Josef Gall s Phrenology - the classification of mental faculties/abilities based on how well specific brain areas are developed If you are better at something then that part of the brain is well developed/would grow Believed you could feel these bumps Jean Pierre Flourens s Tested Gall s ideas of localisationism with lesions in living animals - rabbits, pigeons Remove cerebral hemispheres perception, judgement gone Remove cerebellum problems with motor coordination Remove brain stem death Phineas Gage s Iron rod through frontal lobe lost ability to plan Neural plasticity - ability of neurons to adapt to injury and grow able to compensate for injury survived Lobotomy - neurosurgical procedure - surgical incision into the frontal lobe of the brain to sever one or more nerve tracts Transorbital lobotomies Through the eye Treatment of mental illness Typically done without anesthesia Rosemary Kennedy One of 1st patients Failed - left her permanently incapacitated Spent rest of life in an institution Paul Broca s Patient = Tan 3

4 Lost speech and motor function Language comprehension still in tact Broca s area - highly specialised Speech Motor function Karl Wernicke 1800s Patient Speech in tact Language comprehension gone Wernicke s area - highly specialised Language comprehension Brain activity is localised, but Plasticity - info can be transferred from 1 side of brain to the other if 1 side is damaged/removed Neuro-imaging E.g. MRI (Magnetic Resonance Imaging) Modern day phrenology? The brain is a network! How do we gain knowledge? Who is who in history - remember a few names Molyneux s question to John Locke Nature vs. nurture Nativism vs. Empiricism Body vs. mind Tabula Rasa idea Plato s cave and triangle British Empiricists - Locke, Berkeley Mainland European philosophers - Descartes, Kant Modern Nativist Chomsky and his way of thinking Cases - Genie Nature vs. nurture Nature - most knowledge is present at birth Nurture - you learn, take in info through senses Noam Chomsky s-now Language is an innate faculty of the human mind Humans are pre-disposed to acquire language Ability to learn language = innate component in humans, present at birth Critical period Everyone is born with the ability to learn language - nature Language you learn depends on where you grow up - nurture Nativism vs. empiricism Nativism - concepts, mental capacities and mental structures are innate rather than acquired by learning 4

5 Empiricism - knowledge is based on experiences from the senses Rationalism - reasoning as a source to gain knowledge with parts being innate Aristotle BC Greek philosopher The tubala rasa idea (Latin = blank slate) When we are born our brain is empty Knowledge through perception Plato - 300BC Rationalism (nativism) Some info is innate, we can reason on it can t be empiricism Perception doesn t help to find real knowledge about the world Plato s cave - would the prisoners prefer the world they know or the real world John Locke s Nothing is in the mind which was not first in the senses All knowledge acquired through senses experience is derived from perception One of 1st British empiricists William Molyneux asked him if a person was born blind, would they be able to distinguish objects by sight? ANS: no Body vs. mind Materialism - everything in tissue reductionism (monoism) Subjective idealism (/mentalism/immaterialism/subjective idealism) - without mind reality might not even exist, physical world may be irrelevant (monoism) Interactionism - both mind and body exist, need to talk to each other (dualism) Ludwig Feuerbach s Materialism You are what you eat Bishop George Berkeley s To be is to be perceived Objects can t exist without being perceived Rene Descartes s Interactionism Mind and body interact at the pineal gland Pineal gland - close to ventricles - cerebrospinal fluid delivers messages to nerves behaviour 5

6 Against empiricism - refused to trust his senses, believed they deceive us You can doubt everything except your own existence Nativist Emmanuel Kant s Nativist (most mainland Europeans were nativists) The human mind creates the structure of human experience Noam Chomsky s-now Nativist Language is an innate faculty of the human mind Critical period of language acquisition - past this point in childhood it s impossible to learn language The Wild Boy of Aveyron, Victor s Found roaming woods, France Behaved like a wild animal raised by wild animals Couldn t speak Dr Jean Marc Itard - reputation for teaching the deaf to speak Failed to learn more than a few words despite years of teaching Genie s Supports the critical age hypothesis 1970s - 13yo girl rescued from an imprisoned life Never learnt language Past critical age Impossible to learn language 6

7 Important ideas in Psychology Modern day nativism - Chomsky Innate parts of language acquisition Weber and Fechner - Psychophysics Demarcation in science Clever Hans Subliminal perception Popper, Kuhn Gustav Theodor Fechner s Father of psychophysics Focus on sensory systems We are a product of evolution in a physical environment brain should obey physical rules Ernst Weber s Just noticeable difference Weber s law: the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus E.g. if 5g is the noticeable difference between 100 and 105g 50g will be the noticeable difference between 1000 and 1050g Weber fraction for this task = 5/100 Demarcation - the dividing line between 2 ideas Problem - what is scientific and what is unscientific The scientific method Fact - based on direct observation Theory - an idea to explain facts Hypothesis - prediction of new facts based on known facts Test /experiment - testing hypotheses in a sound way E.g. Clever Hans Horse that could do maths - code by horse hoof 4 years of training with Mr Von Osten Fact - a horse can do maths Theory - animals can learn to do maths Hypothesis - a horse can do maths Experiment Did the trainer give info to Hans? Remove trainer Could still do maths Did the audience give info to Hans? Remove audience - can t see signals of audience to know when to stop tapping hoof (excitement) Couldn t do maths Subliminal perception - stimulus is registered and processed without subject s awareness Subliminal messages affect mood, bias memory retrieval, can t trigger complex behaviour 7

8 James Vicary Flashed drink coke and eat popcorn between frames in a movie Coke and popcorn sales Bans on subliminal advertising Karl Popper s Book - The Logic of Scientific Discovery Falsifiability/refutability - a statement/hypothesis/theory must be able to be tested to potentially prove it false Popper s swans Hypothesis - all swans are white Good hypothesis because can be falsified Find 1 black swan falsified Sigmund Freud Ideas are considered pseudoscience according to Popper s theory Pseudoscience - a collection of beliefs or practices mistakenly regarded as being based on scientific method Thomas Kuhn Book - The Structure of Scientific Revolutions No obvious science/non-science demarcation Paradigm shifts Hard to change - only changes if anomalies show up that are hard to explain by the current paradigm Old theory - well established and understood, many followers, many anomalies New theory - untested, new concepts/techniques, few followers, accounts for anomalies, asks new questions Large changes in the history of psychology Often based on big discoveries Change of zeitgeist - the defining spirit of a time period Max Planck - a new scientific theory triumphs an old one Convince opponents Opponents die and a new generation grows up to be familiar with new ideas 8

9 History of modern Psychology Wundt and structuralism Titchener in the USA - structuralism Introspection as a tool James (Harvard, USA) and functionalism Gestalt movement Perceptual organisation Gestalt law The start of behaviourism and the role of animals Pavlov Watson and Little Albert Thorndike and his puzzle box Skinner and his Skinnerbox Freud and psychodynamic approaches Cognitive revolution Emergence of Cognitive neuroscience Structuralism Search for the primitive experiences that constitute thought Building blocks of our conscious experience Introspection as a technique to look into the brain Auditory sensations, visual (colour, form), tactile (pressure, temp, pain), time The brain puts them together = synthesis, apperception Wundt was a structuralist Edward Titchener s A student of Wundt Based on introspection Look at own conscious experience in search for basic elements of the experience Subjective - self reports on sensations, feelings, emotions Raw data of what subject was experiencing Hoping to find ultimate building blocks Rejected functionalism, Gestalt movement Functionalism Rejection of structuralist ideas USA William James s The godfather of psychology Problem with structuralist approach is the stream of consciousness - continuous arrival of new thoughts can t analyse current thoughts into basic components Gestalt psychology Rejection of structuralist ideas Europe Founders - Max Wertheimer, Kurt Koffka, Wolfgang Kohler The whole is other than the sum of its parts - the whole exists independently of its parts Perceiving is not just sensations - it is a process of organising by the brain Perceptual organisation - a stimulus organises itself Gestalt laws 9