Week 9 - Lecture notes 9 PDF

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Week 9 - Lecture notes 9...

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Colour constancy - Colour of object determined by colour of light it reflects and colour of light that is being shone on it. Determined by product of its reflectance and illumination. - Reflected colour = reflectance x illumination - We continue to see an object as a certain colour regardless of light being shone on it bc we habituate to the colour. - Habituation: If entire scene is under red light: we habituate to red → everything will be seen greener than it is. We’ve become less sensitive to that colour. Discounting the illuminant: we disregard the colour that coats entire scene and thus are able to identify objects w/ same colour between scenes w/ different colour illuminations Music gave sense of continuity → for as long as playing/effective Memory Recall of autobiographic episodes - poor Recall of facts learned prior to illness - relatively good Capacity to learn new facts and episodes poor Ability to attend to and understand current conversation - fully preserved Musical ability - fully preserved What is memory? A set of systems (w particular functions) for encoding, storing, and retrieving information acquired through our senses, and for relating this information to previously acquired knowledge The mental and neural representation of information we have experienced, imagined and learned Encoding, storing, retrieving - acquired from senses Then relating to previous knowledge Encoding → processing of incoming information to be stored Acquisition → registers inputs in temporary sensory storage Consolidation → creates a stronger representation to enable retrieval at a later time (results in storage) Depends on the processes of attention

Visual Search: - Binding required when target contains same features as distractor.

Conjunction search: Process used to when target differs from distractors only by specific conjunction of features (multiple features:

horizontal red bar vs vertical green bar). - FIT predicts → in conjunction search: attention applied to objects one at a time to determine whether it is target or not. Conjunction searches are slow processes. Feature search: process used to when target only differs from distractor by one distinct feature. (red square vs green squares) - Binding problem doesn’t need to be solved and thus process is faster. Uses contrast fixation. Change Blindness: - Attention can determine what we remember. If we don’t attend to it, we won’t remember it. - Changes that are obvious when attention is drawn to them but unnoticed when not attended to → change blindness. Happens in static pictures and in real life. Experiment (Simons and Levin) - Experimenter went up to person in public, asked for directions. Midway through, two people carrying a door pass between them and experimenter is replaced by someone else who continues conversation. - Showed that majority of ppts didn’t notice when person was changed out and showed that change blindness can occur outside of a laboratory. Conditioning = Associative Learning Important to learn associations between stimuli (events) in the environment that reliably predict other stimuli, Especially those stimuli that relate to survival Learning associations between environment that predict other events in the environment Classical Conditioning Learning an association between a stimulus that reliably predicts another stimulus that is naturally associated with a defensive or appetitive reflex response Association between stimulus - predicts another stimulus associated with a reflex response Reflexes are not learned Learning to produce a reflex response to a stimulus (event) that would not naturally cause it Associating other stimulus recurring regularly with presentation of food as signals (predicting future) of food Treat - salivation response - natural reflex before conditioning Unconditioned = unlearned UCS - unconditioned stimulus UCR - unconditioned response Before conditioning - UCS + UCR = reflex A stimulus that does not produce the reflex - neutral stimulus (NS)

During conditioning.. Establishing a conditioned response Present the sound of the bell just before giving the food Association of prediction Predicts future Bell → UCS → response Bell predicts likelihood of food Repeat a few trials in one session, and again after delay (days, a week) Reflex response occurs in anticipation of food Shaping behaviour ie pigeons playing ping pong Closer approximations - reward closer behaviours - ie kid gets interested in toothbrush Shaping reinforces successive approximation to the desired behaviour (reinforcing small steps) • Start by reinforcing high frequency component of the desired response • Then drop this reinforcement - behaviour becomes more variable again • Await a response that is still closer to the desired response - then reintroduce the reinforcer • Keep cycling through as closer and closer approximations to the desired behaviour are achieved • Enables the molding of a response that is not normally part of an animal’s repertoire Reinforce → extinction → reinforce behaviour closer to desired response → cycle through extinction and closer reinforcement 3.1 Why did Seligman and Maier use a tripartite design? Simplest Statement of Instrumental Behaviour - To have something desirable is good, to have something undesirable is bad - Therefore, our current behaviour is selected by its consequences … o Repeat behaviour if they bring us desirable outcomes + learn to discriminate situations when best to repeat these behaviours (same to inhibit behaviours that bring undesirable outcomes) - What if we learn something more from success of failure? - A lot of this started from series of research that stemmed from Pavlov’s discovery of ‘psychic reflex’ o Response generated in expectation to event they have no control over Interference Effect - When exposed to uncontrollable stressors, animal + people develop … o Cognitive impairments:  No longer learn about successful use of behaviour to change outcomes  Transituational impairments  failure in 1 task can generate failure to learn in another o Motivational impairments:  Failure in 1 task leads animals + people to stop any responding in later tasks  Showed apathy to experience, failed to do anything to escape experience o Emotional impairments:

Development of a depressive like state  eating, sleeping, activity etc. compromised Tripartite design to the study … o Escaped + yoked control matched exactly on exposure to stressor o Only difference was controllability of stressor o Compare against normal non-stressed control to determine is effective positive or negative o Not just if you were exposed to stress, but whether you control the stress will determine the long lasting effects (one of first studies for depression) 

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Classically conditioned response come back after extinction YES - spontaneous recovery Rest after a series of extinction trials, and present the bell again - conditioned response will return Independence of phonological loop and visual-spatial sketchpad Independent of each other - can work w visual and sound at same time without interference Therefore support integration of both in episodic buffer Concurrent performance of a visuo-sp[atial task and a phonological recall does not impair performance on either task • ie - visuospatial task such as recalling the pattern of coloured squares on a checkerboard does not interfere with a verbal digit span task Contrast w effect of non-attended speech in the auditory channel while trying to complete wan auditory memory task - the non-attended speech effect occurs when performance on a verbal memory task declines in the present of irrelevant speech ie remembering phone # someone else keep speaking Interference con-current visual spatial tasks 2 tasks in one - sensory channel interference Central executive Executive processes are used in planning and coordinating complex behaviour • Goal orientation • Focus attention • Control of social behaviour • Switching between tasks, updating memory, inhibition of distracting information • Planning and problem solving Executive processes are governed by circuitry in the prefrontal cortex not memory system - intentional system Drawbacks of Punishment Rarely works for long term behaviour change Tends to only suppress the behaviour Does not teach a more desirable behaviour If threat of punishment is removed - behaviour returns (speed cameras) Produces negative feelings - does not promote new learning Harsh punishment - may teach the recipient to use such behaviour towards others

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Short term Tells them what not to do - but not what to do instead Threat removed - behaviour returns Promote -ve feelings in learner Teach learner - this is a good way to solve problems

Two major divisions of LTM: Declarative and Nondeclarative Memory Declarative Memory (explicit) • Knowing what, why and when • Facts, events, locations • Hippocampal dependent Non-declarative Memory (implicit) • Knowing how • Motor skills (e.g. riding a bike) • Cognitive skills (e.g. reading) • Non-hippocampal dependent Declarative - who, what, where, facts and events - depend on hippocampus (ie medial temporal lobe) Non-declarative - know-how, motor skills. Reading, speaking, non-hippocampus Two subdivisions of declarative memory: Episodic and Semantic memories Endel Tulving proposed that declarative memory can be subdivided into the episodic and semantic memory systems Episodic memory • Knowledge of personally experienced events • when/where memories • Contextualised memory • Mental time travel Personally experienced events (unique to humans) Contextualised - bound in place When/where Mental time travel Semantic memory • General knowledge of facts about the world • what/why memories • Abstract

knowledge Abstract Conceptual knowledge, just what you know Declaratie memory is revealed through explicit memory Sub-divisions of Non-declarative Memory Revealed when previous experience facilitates (improves) performance on a task Improvement in performance does not require conscious recollection of the prior learning experiences We get better at things with experience and practice Non-declarative memory is revealed through implicit memory tests Know how Motor skills, reading, speaking, non-hippocampus Memory revealed when past memory has impact on current 11.1 What do these terms mean? – Homeostasis, distress, eustress Mental Illness Rates 45% of people experience a mental disorder throughout their lifetime 20% of these experience a 12 month mental disorder o Of these 14.4% are anxiety o 6.2% are affective disorders (e.g. bipolar, depressive episodes) o 5.1% are substance use disorders Stress Life exists by maintaining a complex homeostasis that is constantly challenged by intrinsic or extrinsic adverse forces (stressors) Under favourable conditions, individuals can be invested in pleasurable functions that enhance their emotional + intellectual growth and development + survival of their species (e.g. food intake + sex) Activation of stress response during threatening situations beyond control of individual can be associated with dysphoria à eventually emotional or somatic disease Hans Selye Early work on physiology of response to stressors in late 1930s Later popularised concepts of stress: o Eustress à stress that enhances function o Distress à persistent stress that is not resolved through coping or adaption Determined by disparity between expectations + experience and resources to cope E.g. Psychological stressors Homeostasis Biological need for homeostasis à maintenance of body’s milieu within a fixed range of conditions - Environmental factors continually disrupt homeostasis o The body contains numerous mechanisms to maintain homeostasis o These are usually expensive/require energy Factors that disturb homeostasis too much = stressors - Dynamic Homeostasis: o Current position of a system is determined by the strength of forces acting upon it o E.g. the position of the arm is determined by …

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 The weight carried in the hand (downward force)  The force applied by the muscle pulling up o Maintaining homeostasis requires ener Maintaining Homeostasis: o Most are examples of negative feedba o E.g. maintaining body temp. o Cold room chills body à too cold à shiver or turn on heater à body warms up à stop response...