My view on and memory Neurobiology of  Learning and Memory For this class: Field is broad and the breadth is important, so we will follow good examples to keep  depth

Stephan Anagnostaras Several different fields cover learning and memory. My view is there should be one field and we would all be in the learning and memory building. Course will come from an eclectic perspective

Several modern disciplines study

neurobiology of learning and memory Learning and Memory  

Psychology Why learning and memory? • Behavioral Neuroscience • Cognitive Neuroscience/Neuropsychology Learning - current views on this term are from the field of learning theory/behavioral psychology. Physiology A relatively permanent change in as the result of • Synaptic Plasticity experience - BF Skinner

Molecular Genetics Memory - current views from in information • reverse, forward, and epigenetic approaches processing theory (cognitive psychology and computer science). Biology The capacity to store and retrieve of information (comp sci) • of birdsong learning The faculty of the mind by which it retains the knowledge of previous thoughts, impressions, or events. (cognitive psych)

Learning versus Memory Origins of the study of L&M

 

Historically there was deep animosity between • The study of learning is closely related to the behavioral & cognitive psychologists. Why? beginning of experimental psychology (around 1900) Problem relates to view of associationism. and, before that epistemology (philosophical study of how we have knowledge) Behaviorism - the cornerstone is behavior because it is observable. Goal is to find lawful Nature-Nurture Debate relationships between external events & behavior Renee Descartes (1641) Nativism - knowledge is innatively given - e.g., Cognitive psychology - a key tenet is the knowledge of God, perfection, infinity concept of an internal representation. This is Rationalism - knowledge gained by reasoning logic how knowledge is stored, and operations can and intuition. occur between representations. Can usually only –In both instances, knowledge is independent of be inferred or known through introspection. experience

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Origins of the study of L&M Origins of the study of memory 

 Ebbinghaus (1885) Aristotle (350 BC) - 4 laws of memory Used introspection to study forgetting in himself 1. Similarity list of 12-16 consonant-vowel-consonant 2. Contrast (CVC) nonsense syllabus (e.g., KEG, MIW) 3. Contiguity 4. Frequency memorize the list by repeating until recalled, then record # of trials and wait 20 min - 31 d John Locke (1690) Empiricism (Associationism) - Relearn the list = SAVINGS knowledge is gained by experience as provided to the mind by the senses. • Most forgetting in first 20 min, very little between -these views advanced by others 20 min and 31 d - esp David Hume in the 1700s -Enquiry concerning human understanding, 1748

Origins of the study of memory Origins of the study of memory 

 Ebbinghaus also discovered serial position effect (primacy & recency effects)

Glanzer, M. & Cunitz, A.R. (1966). Two storage mechanisms in free recall. Journal of Verbal Learning and Verbal Behavior, 5, 351-60

Origins of the study of memory 

 William James (1890) Serial • argued there must be at least position two types of memory effect is ubiquitous Primary memory -information currently contained in consciousness

Secondary memory -stored information which can be brought into consciousness

First of many suggestions that there were multiple memory systems.

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Origins of the study of memory Origins of the study of learning

  Behaviorists tended to be somewhat hostile and engaged in many turf battles The study of memory developed into information processing theory in the 1960s In the domain of clinical psychology they were battling it out with the psychoanalytic approach. * Multi-store Memory System Very much against introspection, tended to become * Sensory Memory extreme in this domain, and rejected cognition as * Short Term Memory * Long Term Memory well.

* Information Processing in Memory In the domain of animal behavior, they were * Encoding battling it out with the ethologists. Ethologists * Storage believed everything was innate and nothing was * Retrieval learned, hence behaviorists believed nothing was innate and everything learned.

Behaviorist Tradition Behaviorism

 

Behaviorism focuses on objectively observable behavior John B Watson, the and discounts unobservable mental activities. father of American Behaviorism Behaviorists mostly studied animal and human learning focusing on observable behavior and ways to change – Began a scientific behavior. Their studies of learning came to be known movement for as learning theory and their studies of how to Psychology, against change behavior is known as behavior modification several mystical squishy fields, esp. • Largely relationships between external stimuli and Freudian events and their ability to influence behavior Psychoanalysis

Radical behaviorism allows no intervening processes (e.g., BF Skinner) while other forms are more lenient.

Watson & Raynor's famous experiment with "Little Albert" Watson & Rayner's (1920) famous experiment with "Little Albert"

 

3 Watson & Rayner's famous experiment with "Little Albert" Behaviorism of the time was very anti-

genetics, in part because of the evil mental

  testing movement Give me a dozen healthy infants, well- formed, and my own specified world to bring them up in and I'll guarantee to take any one at random and train him to become any type of specialist I might select--doctor, lawyer, artist, merchant- chief, and yes, even beggarman and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors - John Watson

Concept of "Tabula rasa" - organisms John Watson and are born as blank slates Rosalie Rayner

Tabula rasa v. intelligence Russian Reflexology

 

• Notice our education system is still scarred by the nature-nurture debate

• “Social scientists” who think everything is nurture US UR CS

• Mental testers who think everything is nature

• As a result, very little study of genetics of CS CR learning until 1992 CS-US pairing

Pavlov’s Little Albert Learning and Performance

 

Distinction between learning/memory and performance an important problem in animal and human studies

Learning can only be inferred by performance: in humans, a response or a change in behavior in rats, a change in behavior

• Performance may not occur:

Latent learning [Tolman & Honzik (1930)] CR Test anxiety

• Require extensive controls

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Operant/Intrumental Operant/Intrumental

 Conditioning Conditioning

Law of Effect (1911) Response is paired “Of several responses made to the with an outcome (appetitive or same situation, those which are aversive), accompanied by or closely followed R-S* by satisfaction to the animal will, all Edward Thorndike other things being equal, be more Response increases firmly connected with the situation, so -Positive -app that, when it recurs, they will be more -Negative Reinforcement-avs likely to recur… discomfort… weakened. The greater the Response decreases satisfaction or discomfort, the greater -Punishment -avs the strengthening or weakening of -Time-out/Diff Reinf Other -app the bond.”

Behaviorism split into two camps Learning theory today

 

Learning theory - theories relating Learning theory was more successful but environmental events and behavior could ultimately self-destructed by dozens of have a limited number of inferred wrong assumptions, most of which were processes & phenomena excessively simplistic e.g., , generalization, etc. • equipotentiality of stimuli Radical behaviorism - could only make • single associative value laws between behavior and environmental • indepedence of path events (only things that are observable)- • invariance of path typified by Skinner

Learning theory today

 

• Survives primarily as a subdiscipline Cognitive Psychology emphasizes internal of behavioral neuroscience mental representations and operations between them, both it and computer science are referred to as information • Strong integration of principles and theory. Memory and knowledge are rigor into other fields of study cognitive terms. Tolman emphasized flexibility of animal knowledge, in contrast to the very Edward Tolman mechanistic views of most behaviorists

Also rejected the idea of Tabula rasa

5 Tolman's path integration Tolman & Tryon: Selective breeding of

maze bright and maze dull rats

 experiment

Influence of Rearing Environment

 

Cooper & Zubeck (1958) compare with Enrichment first done Rosenzweig & Tryon (1950) by D.O. Hebb (1949)

Behavioral Neuroscience &

Neuropsychology

 Neuropsychology

• Studies the breakdown of function after brain damage in humans

• First original case of Lebourgne by Paul Broca (1861), Broca’s language production area (Wernicke-1894 - language reception)

Strong push toward localization of function Early push was from Gall’s Laws of equipotentiality Karl Lashley, father of Organology (Spurzheim’s Phrenology) and mass action Behavioral Neuroscience Read the critique by S.I. Franz

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Neuropsychology Neuropsychology

 

Theodore Ribot (1882) Alois Alzheimer (1906) Reported an institutionalized female patient with -Reviewed cases of retrograde amnesia progessive dementia. After being shown objects associated with brain damage and recognizing them, she immediately forgot them and circumstances under which she learned --in most cases memory acquired remotely before them. Both anterograde and retrograde amnesia the insult was preserved compared to that were present, and obeyed Ribot’s law as well. acquired recently Sergei Korsokoff (1887) --Ribot’s law of regression - loss of memory is Memory impairment in chronic Alcoholics which inversely related to the time elapsed between the obeyed Ribot’s law. event to be remembered and the injury. Ribot concluded memories need a certain amount of time to become organized and fixed.

Neuropsychology Neuropsychology 

Georg Muller & Alfons Pilzecker (1900) - large number of experiments in normal subjects Several interesting case studies since then, but -same as Ebbinghaus, but nonsense syllables in pairs the most influential was not until the 1950s. -Recall second item when probed with first from pairs

-Spontaneous recall of pairs from the same list Phenomenon of consolidation not studied a (perseveration) which had a time-gradient of a few whole lot by animal learning people until minutes -- speculated reflected transient brain activity recently

-Put distractor lists between training and recall, get Phases of memory are a recurring theme which retroactive interference -- this follows a time gradient so that distractors are only effective for a few minutes we will struggle to understand throughout the class. --Concluded brain activity perseverates after new learning and activity serves to consolidate memory.

Where are we today?

 

• Further than any other area of neuroscience - not very far

• Strong stratification of the study of learning and memory hinder vertical integration

• Try to build an interdisciplinary framework from molecules to cognition

• No single engram identified at the molecular- genetic level

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