Psych Unit 3

Sensation

the passive physical process of recieving info/stimuli about the world from sense organs abd then turning it into neural signals to send to the brain via transmission

Perception

the active, psychological process of selecting, organising and interpreting the information brought to the brain

Processes of sensation

1) Reception, 2) transduction, 3) transmission

Reception (1st process of sensation)

physical stimuli are detected by sensory receptors in the sense organs

Transduction (2nd stage of sensation)

stimuli are converted into electro chemical energy

Transmission (3rd process of sensation)

the electrochemical energy is transferred to the CNS for processing

Perception processes

1) selection, 2) organisation 3) Interpretation

Selection (1st process of perception)

brain filters stimuli, selects relevant features for processing and ignores irrelevant and unimportant information

Organisation (2nd process of perception)

Grouping selected features of stimuli to form a whole, by organising stimuli into patterns

Interpretation (3rd process of perception)

the brain interprets the information, giving it meaning and drawing on past expereinces

Memory

the internal record of previous events of experiences that is maintained over time

Processes of memory

1. Encoding

2. Storage

3. Retrieval

Encoding

refers to the conversion of sensory information from the environment into a form that can be processed by the brain

Storage

refers to the retention of the information received from the environment and creating a permanent record for it

Retrieval

the recovery of information stored in the brain for use and manipulation

Multi-store model of memory (Atkinson and Shiffrin, 1968)

A three stage model of memory where information is processed through sensory memory, short term memory and long term memory

Sensory register

Stores the basic information received from the senses, has an unlimited capacity, a duration up to 5 seconds and it’s encoding involves iconic and echoic encoding

Short term memory

the information that you are aware of that can be held onto for a short period of time for conscious use, has a capacity for 7 (± 2) pieces of information, a duration up to 30 seconds, encoded through rehearsal

Maintenance rehearsal

involves constant repetition of the information to increase it’s duration in the STM

Elaborative rehearsal

encoding information by associating it with other information in the LTM to make it more meaningful so it can be stored in the LTM for later use

Long term memory

a relatively stable, permanent store of information that can be accessed and manipulated at will, has an unlimited capacity, relatively permanent duration, uses semantic encoding

Declarative memory (explicit)

LTM store for specific factual information or past events, has two subsections: semantic and episodic

Semantic memory

Stores knowledge of facts and information regarding the meaning of things

Episodic memory

Stores memories of past events and experiences, particularly ones with a personal or emotional significance/importance

Procedural memory (implicit)

Concerns knowing how to do things and enables us to carry out learnt tasks without conscious effort

Strength of MMM

there is lots of evidence supporting the idea there are differences between STM and LTM

Limitation of MMM

Model is oversimplified, too linear and passive

Working Memory Model - Baddely and Hitch (1974)

Emphasises the active nature of processing memory rather than passively, describes four seperate but interdependent aspects of working memory; The Central Executive, The Phonological Loop, The Visuospatial Sketchpad and the Episodic Buffer (added in 2000)

Central executive

The “master system” responsible for directing attention to relevant information and coordinating the “slave” systems

Phonological loop

Deals with spoken, auditory and written information

Visuo-spatial sketchpad

Stores visual and spatial information

Episodic buffer

Integrates information from the phonological loop, visuospatial sketchpad and LTM to form a single structure or episode

Hippocampus’ role in memory

involved in encoding and storing declarative memories

Henry Molaison case study (1953)

Had his hippocampus removed to treat his epilpesy, experienced anterograde amnesia (unable to remember anything after the injury), but was still able to learn new motor skills and his STM was still intact

Henry Molaison case study (1953) - ethical considerations

Withdrawal rights were upheld - he was able to remove himself from the study

Confidentiality was breached - his name is well known

Remembering

refers to the cognitive process of retrieving previously learnt and stored information and bringing it into conscious awareness

Recall

the ability to retrieve a memory using minimal cues or prompts

Recognition

Identifying the correct information from a series of alternatives

Relearning

process of a person learning information or skills again that they have previously learnt but has since forgotten

Craik and Lockheart’s Levels of Processing Model of Memory (1972)

Focuses on the depth of processing involved in memory and predicts the deeper the information is processed, the longer a memory trace will last and the easier it will be to retrieve

Craik’s definition of depth

the meaningfulness extracted from the stimulus, rather than in terms of the number of analysis performed upon it

structural processing (shallow processing)

Encoding only the information’s physical qualities

Semantic processing (deep processing)

processing the information by what it means

Phonemic processing (shallow processing)

Encoding information by it’s sound through maintenance rehearsal

Ebbinghaus Forgetting Curve (1885)

A graphical curve of the forgetting process, illustrating how our ability to retain information diminishes over time, majority is lost in the first hour after learning the information, after 3 days the rate of forgetting is quite stable

Spaced repetition’s affect on the forgetting curve

Ebbinghaus theorised that each repetition in learning increases the optimum interval before the next repetition is needed

forgetting

a failure to retrieve previously stored information

Retrieval failure

the inability to recover and access a particular piece stored information due to an absence of retrieval cues or external cues

Tip of the tongue phenomenon

the sensation that you know something you just can’t retrieve

internal retrieval cues

aspects of individual’s physical and cognitive environment that can trigger the memory

External retrieval cues

information about the situation and environment in which a memory was formed that can trigger the said memory

Interference

forgetting occurs due to the competing presence of other information being stored

proactive interference

old information hinders recall of new information

retroactive interferance

new information hinders recall of old information

Motivated forgetting

the process of blocking out threatening, embarrassing or painful memories, done consciously or unconsciously as a self-protective defence mechanism

Repression

unwanted thoughts or impulses being unconsciously pushed out of awareness into the subconscious mind

Suppression

the act of consciously forgetting painful or upsetting memories

Decay theory

memories fade or biologically degrade over time

Process of forgetting

neurochemical changes/memory traces occurring when new information is learnt start to disintegrate and become less frequent leading to forgetting

Degeneration

A build up of proteins in the form of amyloid plagues and neurofibrillary tangles in the brain, causing brain cells to die over time

Alzheimer’s disease

a type of dementia characterised by the gradual widespread degeneration of brain neurons progressively causing memory decline

Chronic Traumatic Encephalopathy

Brain injury caused by repeated head injuries, causing the death of nerve cells in the brain, getting worse over time

Drug Induced Wernicke-Korsakoff syndrome

a neurological condition caused by chronic alcohol use, causing a thiamine deficiency in the brain (reducing the amount of energy the brain has to process and retrieve information)

learning

a relatively permanent change in behaviour resulting from experience

stimulus response

learning occurs due to a response to a stimulus in an environment

Associative learning

occurs when two things are paired together in time and/or space

Classical conditioning

learning that takes place when an originally neutral stimulus comes to produce a conditioned response because of it’s association with an unconditioned stimulus

Stimulus

an object or event that can be detected by the senses

response

the resulting measurable behaviour from a given stimulus

unconditioned stimulus

a natural stimulus that results in a natural response

unconditioned response

a natural response to the natural stimulus

conditioned stimulus

A formerly neutral stimulus that is associated with a conditioned response

Conditioned response

a response to a conditioned stimulus in the absence of the unconditioned stimulus that would normally cause it

neutral stimulus

a stimulus that does not produce a response (biologically neutral)

acquisition

the learning stage during which a conditioned response comes to be elicited by a conditioned stimulus

rule 1 of classical conditioning

the neutral stimulus becomes the conditioned stimulus

rule 2 of classical conditioning

the unconditioned response becomes the conditioned response

stimulus generalisation

occurs when a stimulus similar to the conditioned stimulus produces the same conditioned response

Discrimination

the ability to distinguish between one stimulus and other similar stimuli and henceforth only responding to the specific stimuli

Extinction

the gradual weakening and eventual disappearance of the conditioned response after the conditioned stimuli is no longer paired with the unconditioned stimuli

Spontaneous recovery

The reappearance of a conditioned response when the conditioned stimulus is presented, following a rest period

Little Albert experiment (1920) aim

to identify whether or not human emotional responses are learned from enviromental stimuli, to provide experimental evidence for classical conditioning

Little Albert Experiment method

a 9 month old baby was exposed to neutral stimulus - white rat, rabbit, monkey mask, a loud banging noise (US) was paired with NS

Little Albert findings

After repeated pairings, Albert began to cry when only exposed to the rat + showed stimulus generalisation - would cry when exposed to similar stimuli such as a Santa Clause mask

Little albert criticisms

Low external validity - only one participant was used + didn’t uphold protection from harm

Operant conditioning

learning involving voluntary behaviours rather than reflexive/automatic responses

Antecedent

the stimulus/event occurring before the behaviour

Behaviour

a voluntary observable action or response that occurs due to the antecedent

Consequence

the outcome to the behaviour

reinforcement

a consequence that causes a behaviour to occur more

punishment

a consequence that causes a behaviour to occur less

continuous reinforcement

reinforcing a behaviour every time it occurs

intermittent reinforcement

some but not all correct responses are reinforced

Fixed ratio

rewards a particular response only after a defined number of demonstrations of that response

fixed interval

rewards a learner for the first correct response after a defined period of time

variable ratio

rewards are given after an unpredictable number of desired responses are exhibited

variable interval

rewards a correct response after an unpredictable amount of time

systematic desensitisation

a type of behavioural therapy used to reduce a phobia, involving exposing a person to their phobia stimuli/situation gradually under relaxed conditions until the fear response is extinguished

phobia

an intense or irrational fear or aversion to an object/situation which persists over time

graded exposure

a process that introduces a phobia inducing stimuli in degrees from least to most fearful whilst the sufferer maintains relaxation and comfort