memory unit 3

sensory definition

the physiological process involving sensory receptors decting/responding to stimuli

stages of sensation

reception, transduction, transmission

reception

the stimulation of sensory receptor cells

the presence of physical stimuli is detected by sensory organs

transduction

converting energy of the stimuli into electro-chemical signals

e.g. kinetic energy from a ball that hit someone converts into electro-chemical signals

transmission

the delivery of neural information to the brain for processing

e.g. transferrring info from electro-chemical signals abt being hit by a ball to parietal lobe

perception definition

the mental process of organising and interpreting sensory stimuli so that is it meaningful

stages of perception

selection, oganisation, interpretation

selection

the brain filters stimuli selecting important features for further processing while ignoring unimportant features that will receive no further processing

e.g. looking out a window and seeing a bird, filtering out a person running

organisation

the stimuli chosen to be attended to is arranged into patterns that are meaningful and easy to understand

interpretation

assigning meaning to experiences using mental structures

interpretations are determined by beliefs, experience, needs, values, involvement

subjective

perceptual expectancy

past experiences that leads to built up expectations on how to perceieve and respond to a certain stimuli

selective attention

the process of focusing on a particular object in the environment for a certain period of time

allows to tunes out unimportant details and forcus on what matters

divided attention

where mental effort is divided between two or more tasks or stimuli simultaneously

e.g. driving a car

cocktail party effect

cherry 1953

cocktail party effect aim

to study the human ability to selectively focus on one auditory message while filtering out other competing sounds

CPE fidnings

we have the ability to selectively attend to certain stimuli while filtering out other stimuli

ppl have the ability to switch their attention back and forth between selected stimuli

unattended auditory info reieves little processing

CPE contributions

to the study of how we are able to select what we need to pay attention to and how we process auditory stimuli

CPE criticism

oversimplification of what happens in real world

—> there will be more stimuli to select where to put attention to

memory

The internal record of some previous event, a process in which info is encoded, stored, and retrieved

Aspects of memory

Encoding

Storage

Retrieval

Encoding meaning

Conversion of info into a form that can be stored by the brain

Storage meaning

Info that is held for various amounts of time

Retrieval meaning

The process that locates stored info and returns it to consciousness as required

Multistore of memory

Atkinson + Shirrin 1968

Multistore of memory stages

sensory store

short-term memory

long-term memory

sensory store overview

where everything is kept until 1st stage of perception (selection)

info from senses

main function is to hold incoming info long enough to be processed further

5 separate sensory registers act as storage bins for different senses, such as iconic memory (visual), and echoic memory (auditory)

sensory store capacity, duration, encoding

capacity: unlimited, stores all incoming sensory info in the memory registers from the 5 different senses

• important info that is needed to be attended to is passed to STM

duration: up to 3 seconds + quickly fades

encoding: rapid, based on physical properties of stimulation (e.g. sound)

• as a sense + attention

• helps w experiencing constant flow of info

• selective attention focuses mental resources on only some of the sensory stimuli

• echoic memories fade slower than visual

short term memory overview

conscious info (current thoughts, words & images available for decision making and problem solving

STM capacity, duration + encoding

capacity: 5-9 chunks of info

• greater for digits

• better for echoic info than iconic

• better for echoic than iconic information

duration: ~ 30 seconds

• 5-18 seconds w/o rehearsal

• adaptive by getting rid of useless information

encoding: rehearsal (allows transferral of materials to LTM)

• maintenance rehearsal

• elaborative rehearsal

• chunking

maintenance rehearsal

remembering info for immediate use, not to transfer to LTM

• often repeating

• e.g. remembering a numberplate to report for a hit and run

elaborative rehearsal

active processing and encoding of info by associating it w other info in LTM (assimilation/accommodation) to make it more meaningful so it can be stored in LTM for later use

e.g. relating psych course content w events of life

chunking

process of combining info into larger, meaningful groups based on patterns

• more info to hold as STM holds 5-9 meaningful info

• used to increase STM capacity along side using rehearsal and elaborative memory

• e.g. remembering a phone number with the first 4 digits being a birthday

Long-term memory overview

relatively permanent store of info

• info moves from STM —> LTM through physical changes in neurons and neural networks to make associations, therefore sotrage is permanent

2 types: procedural and declarative

procedural memory

the way things are done- “how to” memory

• memory of actions & skilled learned

• not conscious memory process & mainly refers to learning of motor skills (implicit memory)

• requires little effort to retrieve (autonomic) as skills are well established and learned

e.g. riding a bike, swimming, holding a pen

declarative memory overview

memory declaring how things are or what is remembered

• requires conscious effort for retrieval (explicit memory)

2 types: episodic + sematic

episodic memory

memory of past experiences

• interpretation of experiences in life + remembered bc of personal importance

  • linked to feelings and sensations to a particular time

• e.g. the birth of a younger sibling

sematic memory

memory of facts and info based on understanding and interpretation

• often spoken or written material

e.g. remembering the lobes of the brain and their functions

LTM storage capacity, duration, encoding

capacity: unlimited, but subject to distortion

• memories can be remembered remarkably well after long periods of time

duration: >30 seconds- forever BUT can decay

encoding: physical changes to neurons

often a result of conscious processing (usually semantic coding where details are left out in favour of the more general meaning of the infornation

• this means mistakes can be made about details

1st working memory model

baddeley + hitch 1974

• 2 slave systems

• slave systems: the workhorses of memory + executive drives the memory

• central executive: responsible for organising infon+ coordinating slave systems

  • directs attention to relevant info + supporesses irrelevant info

• pholological loop, central executive, visuospatial sketchpad

phonological loop

stores and processes sounds of language (phonological info) and rehearses it silently

visuospatial sketchpad

stores iconic and spatial info, constructs and manipulates visual images including details of shape, colour, motion, pattern and position, and representation of mental maps

episodic buffer

links info across domains to form intergrated units of visual, spatial, and verbal info w time such as memory of a story or movie

2000 updated model

hippocampus overview

curved shaped deep w/in each temporal lobe

acts as a hub, consolidating various elements of memory into cohesive memory representations

an early storage place for new LTM and invovled in the transition of LTM to more permament ones

interacts w other brain regions to create memories

hippocampus memory formation

important in organisation of storage of new memories, especially declarative

• makes memories stronger by connecting sensations and emotions (works with amygdala)

hippocampus storage of memories

memories temporarily stored in hippocampus before being transferred to pre-frontal cortex

• info circulates whist neurons start to encode info through long-term potentiation

  • form of neural plasticity

    • strongest circulating info returns to brain area it originated from to turn stm-ltm

spatial memory and navigation

hippocampus

rear part involved in processing spatial memories

• to encode environment around us and remember where everything is (contains cognitive map)

Henry Moliason procedure

scoville peformed in 1953

• partial medical temporal lobe resection

• removes medical portions of temporal lobes

• extends 8cm toward the back of the brain in each lobe

• removed the pair of amygdala and majority of the hippocampi in each lobe

  • goal was to control seizures

HM post surgery

demonstrated regrograde and anterograde amnesia

• suffered from retrograde for the 11 year period before surgery, childhood memories unaffected

• demonstrated inability to form declarative memories

• at the time of surgery medical community did not know what the hippocampus did

HM conclusions and contributions

until the surgery, the hippocampus was not know as essention for making memories

• case indicated procedural memories are not controlled by hippocampus & amygdala

• inability to form declarative memories left to conclusion that hippocampus is vital

cerebellum overview

located under cerebrum

involved in balance, coordination skills of fine motor skills and judging distance

invloved in the formation and storage of procedural memory

cerebellum formation of memories

formation of procedural memories

• unconscious/implicit memories (such as motor skills)

  • e.g. how to draw a certain shape

cerebellum sotrage of memories

involved in storage of procedural memories

• specifically sensorimotor skills

amygdala overview

collection of nuclei deep within each temporal lobe

involved in processing emotions and memories associated eith fear

has high connections to other brain functions-can link areas to process higher cognitive information with systems that control lower functions

• fight or flight

amygdala formation of memories

fearful memories established w only a few receptors

• attributes emotions to memories, the more emotive memories are, the easier to remember

amygdala storage of memories

strenghtens episodic memories stored in other regions of the brain (has connections to other brain functions)

• bidirectional connections w hippocampus

• current understanding is suggested that it does not sore memories

CPE method

presenting participants with 2 different audios simultaneously rhough headphones, asking them to repeat one message while ignoring the other. This is to test their ability to selectively attend to a single stimulus

1. sensory memory

2. working memory

3. long term memory

4. retrieval

5. encoding

6. rehearsal

7. attention

8. interference

9. interference

10. decay

11. memory loss

1. central executive

2. phonological loop

3. visuospatial sketchpad

4. episodic buffer

5. rehearsal