5151Psychology Unit Three Notes Burbs

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Psychology Unit Three


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RESEARCH METHODS A research method is a way to conduct a study to collect accurate and reliable

information about behaviour and mental processes.

EXPERIMENTAL RESEARCH Experiments are used to measure the relationship between two or more

variables.

o Variables are factors that can change in amount or type.

Independent Variables (IV) are controlled by the researcher;

Dependent Variables (DV) are used to measure the effect of the

IV.

Control conditions IV absent.

Experimental conditions IV present.

o Compare the two.

RESEARCH HYPOTHESIS

A tentative and testable prediction of the relationship between two or more

variables.

o In experiments, it is an educated guess of how the IV alters the DV.

Must have iPod

o Independent variable;

o Population;

o Operationalised (how it will be practiced);

o Dependent variable.

EXTRANEOUS VARIABLES

Variable other than the IV that can change the DV, disallowing a proper

conclusion as researchers are unsure what affected the DV.

Confounding Variables

Variable other than the IV that has an unwanted effect on DV.

o Different to extraneous variables as it:

Has a measurable change in the IV;

Is consistent with the hypothesis.o Both can cause isolation problems.

TYPES OF EXTRANEOUS AND CONFOUNDING VARIABLES

Individual participant differences differences in characteristics between

participants.

o Affects their responses.

Demand characteristics cues by researcher (or are just present) that have the

participant feel they should behave differently.

o Biases;

o Invalid;

o Possibly also due to social desirability.


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Single-blind means participant is unaware of the condition they are in.

Double-blind means neither are the researcher.

o Use third party to allocate.

Placebos

The experimental group may experience demand characteristics of pills (or other)

so to negate this, you give the control group a placebo to balance it out.

Standardised instructions and procedures

Predetermined.

Identical.

Questions anticipated.

Alternatively, automation to remove any bias.

TYPES OF EXPERIMENTAL AND RESEARCH DESIGNS Repeated measures design each participant is involved in both conditions.

o Consider order effects;

Time period between repeats.

o Eliminates confounding variable of participant differences;

o Fewer people;

o Does not control demand characteristics;

o Can lead to participant attrition;

o Counterbalancing may be used to remove order-effects.

Matched-participants design select similar (Relevant characteristics) pairs and

split into groups to allow for relatively equal groups.

o Variables are constant amongst conditions;

o Difficult and time consuming;

o Pre-testing can lead to order-effects or demand characteristics;

o Random allocation is usually sufficient.

Independent-groups design allocates each participant randomly into one of two or

more separate groups.

o Random allocation used.

o Simplest is experimental and control conditions.

TECHNIQUES OF QUALITATIVE AND QUANTITATIVE DATA COLLECTION Qualitative is information about the characteristics of what is being studied.

o Descriptions, words etc.

Quantitative data is information about amounts of what is being studied.

o Raw scores, means, p-values etc.

All types of mental behaviour can be expressed quantitatively.

CASE STUDIES

Intensive, in-depth investigation of certain behaviours or events of interest in an

individual, small or group situation.

Often used where large numbers of participants are not available.o Advantages:


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No manipulation of variables, thus not artificial;

Can be used as a source for a hypothesis.

o Limitations:

Time consuming;

May not be representative;

Susceptible to bias;

Cannot be the sole test of a hypothesis.

OBSERVATIONAL STUDIES

Observation refers to any means by which a phenomenon is studied.

Involves collection of data by carefully watching and recording behaviour as it

occurs.

o Naturalistic observation observe in natural setting without disrupting;

o

Participant observation the researcher participates;o Non-participant observation observes inconspicuously.

o Advantages:

Not artificial;

Long term effects can be studied;

Some behaviour is only field-observable;

Does not require cooperation (unethical).

o Limitations:

Causes of behaviour not always clear.

Susceptible to bias.

SELF-REPORTS A participant's spoken or written responses to questions or instructions presented

by a researcher.

Questionnaire, interviews.

o Advantages:

Efficient for large numbers (Qnnrs);

Anonymity;

Consistency.

o Limitations:

Social desirability;

Inflexible; Relies on willingness to answer.

ANALYSING AND INTERPRETING DATA Descriptive statistics used for analysing, organising, summarising and

describing the results.

Inferential statistics used for interpreting and giving meaning to results.

o Like descriptive they use mathematical procedures;

o Unlike descriptive the involve judgements.

MEASURES OF CENTRAL-TENDENCY Data is often summarised into understandable and usable forms.


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Mean, mode, median.

Used when scores are evenly distributed,

Data can be shown in tables, graphs etc.

INFERENTIAL STATISTICS

Enable researchers to draw conclusions.

o Whether generalisation can occur.

Used for making judgements about what results mean.

Statistical significance is used to indicate whether a difference in experimental

and control condition is due to IV alone,

o P-value is an estimate of probability of observed difference being due to

change is significant.

CONCLUSIONS & GENERALISATIONS Conclusion is a decision or judgement of what results mean.

o Hypothesis is supported or rejected but never said to be true.

Generalisation is extending findings of a sample to their applicability to the

population studied.

RELIABILITY

Consistency, dependability and stability of results.

Demonstrated when the overall pattern of results is consistent in repeats.

VALIDITY

The extent to which a research study has produced results that accurately

measure the behaviour/event it claims to study.

A measurement tool has construct validity if there is evidence it accurately

measures that behaviour/event.

Research may not be valid if data does not justify conclusion or there are

EV/CVs.

Internal validity is the soundness of the processes; external validity is how well it

can be generalised.

ETHICAL PRINCIPLES AND PROFESSIONAL CONDUCT IN PSYCHOLOGICAL

RESEARCH Standards that guide individuals to identify good/desirable/acceptable conduct.

Ensure wellbeing of participants and promote beneficial research.

Must only be conducted by those who are competent and the researcher must

act ethically.

PARTICIPANTS RIGHTS

Confidentiality

o Right to privacy.

Voluntary participation

o Consent to be involved;


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o No negative consequence to refuse participation.

Withdrawal rights

o At any time without explanation.

Informed consent procedureso Nature/purpose explained where applicable.

Debriefing

o Clarify understanding of research

o Ensure no negative effects

o Clarify deception

Use of deception

o If necessary but cannot cause distress and must be followed by

debriefing.

ROLES OF ETHICS COMMITTEES

Assess proposals for approval.

Main roles:

o Ensure research is ethically designed and conducted.

o Ensure the researcher(s) are experienced and qualified.

o Monitoring approved research,

o Complaint management.

o Ensuring accountability of researcher(s).

NHMRCPRINCIPLES1. Integrity is a commitment by the researcher to search for knowledge in an honest

and ethical way.

2. Respect for persons means that the researcher must be mindful of the welfare,

rights, beliefs, perceptions and customs and culture of participants.

3. Beneficence describes the researchers responsibility to maximise potential

benefits of the research and minimise harm or risk.

4. Justice is that any burden or benefit of research is uniform within the population

and similar for any participant in the study.

USE OF ANIMALS IN RESEARCH 10% of research is conducted on non-human participants.

Could be as:

o Participants are unavailable/harm would occur;

o Starting point to learn about human behaviour;

o Animals have some practical advantages as they breed quicker and have

shorter lifespans;

o Better control;

o No real participant variables.

Issues include unethical and cannot really generalise.

Must only be done if there is no other alternative If given surgery, animals need to be anaesthetised.


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If they are to be put down, must be done quickly and

painlessly.

REPORTING CONVENTIONS Done to communicate results and allow for replication.

Must have enough information for close analysis of

specific aspects and follow reporting conventions.

o Well establish widely recognised standards of

how a report is written.

STATES OF CONSCIOUSNESS

DESCRIBING CONSCIOUSNESS Consciousness is the awareness of objects and events

in the external world, our own existence and mental

experiences at any given moment.

Attention enables us to be aware of some stimuli and

ignore others.

It is a psychological construct as it is a concept designed to describe a

psychological process that is believed to occur, but cannot be measured.

RENEDESCARTES Consciousness includes everything we are aware of.

Thinking provides evidence of consciousness and knowledge of our own

existence.

o Cogito ergo sum I think therefore I am.

Dualism: The mind and body are separate but interact through the pineal gland.

WILLIAMJAMES

Consciousness includes everything we are aware of, including our own

existence.

It is like a stream; constantly flowing with images and sensations and thoughts.

It is:

o Personal: Your subjective understanding;

o Selective: You can choose to ignore certain stimuli and attend to other;

o Continuous: Always there, a stream of consciousness;

o Changing: New information is always being processed.

Has an evolutionary based role as it enhances our ability to adapt to the

environment.

STATES OF CONSCIOUSNESS Level, degree or condition of awareness. Two categories:


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o Normal waking consciousness;

o Altered state of consciousness.

NORMAL WAKING CONSCIOUSNESS (NWC)

The state of consciousness associated with being awake and aware of external

stimuli.

Includes the upper half levels of consciousness.

We continuously change between levels of awareness.

Attention is the concentration of mental activity on specific stimuli whilst ignoring

others.

More attention is required in NWC than in ASC.o Selective attention is attending to certain stimuli by choice but ignoring

others.

o Divided attention is the ability to distribute attention amongst stimuli.

Complex tasks require selective attention.

Content can be limited through selective attention (more logical and organised).

Controlled processes are where the process involves conscious, alert awareness

where attention is focused on achieving a particular goal.

o Controlled processes are often serial (one at a time).

Automatic processes require little conscious effort and minimal attentions.

o Often parallel, i.e. two or more at the same time.

ALTERED STATE OFCONSCIOUSNESS

Any state of consciousness distinctly different from NWC in terms of awareness,

experience and quality of sensations.

Some are natural and some are induced.

One of two effects on sense:

o More receptive to external stimuli;

o Dulls them so some sensations are not felt at all.

In an ASC:

o Perceptions may be distorted so we lose a sense of identity;o Cognitive functioning is impaired;

o Thinking more illogical;

o Time is often distorted;

o Emotions either dulled or intensified;

o Lose self-control.

Daydreaming

An ASC where we shift attention from external stimuli to internal thoughts.

Naturally occurring and more likely to occur when stationary.

Associated with few eye movements and high levels of alpha brainwaves. We have control over the content but it is less organised.


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Proposed that they facilitate problem solving and act to reduce stress by letting

us fantasise.

Meditative state Use of a technique to alter NWC and induce an ASC of deep relaxation.

Done by ignoring external stimuli so senses are less receptive.

Attention is directed at only one stimulus perhaps breathing or a certain word.

Increase of alpha and theta waves, reduction in heart rate and other physiological

characteristics.

Alcohol-induced state

Change in NWC due to consumption of alcohol.

Psychoactive drug it changes awareness/perception/moods.

o Caffeine, nicotine.

Alcohol lessens inhibitions by depressing neural activity for judgement and self-

control.

May experience:

o Shortened attention span;

o Impaired perceptions;

o Impaired thinking;

o Slower reaction times;

o Reduced self-awareness;

o Impaired emotional awareness/control;

o Impaired perception of time;

o Less self-control.

METHODS USED TO STUDY LEVEL OF AWARENESS INNWC

A psychological construct is a concept used to describe activity/patterns of

activity that are believed to exist but cannot be directly measured.

Electroencephalograph (EEG)

A device that detects amplifies and records general patterns of electrical activity

of the brain.

Detects and amplifies brain waves.

Frequency is the number of waves per second, amplitude is the magnitude ofbrainwaves.

Brain Waves

Beta Waves

o High frequency, low amplitude.

Awake, alert NWC or REM.

Alpha Waves

o Medium frequency, medium-low amplitude.

Awake/relaxed state (hypnogogic)

Theta Waveso Medium frequency, high-low amplitude.


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NREM 1, 2 and first half of 3.

Delta Waves

o Low frequency, high amplitude.

Low frequency, high amplitude. NREM 3 (2nd half) and 4.

Heart Rate, Body Temperature and Galvanic Skin Response (GSR)

Changes in heart rate & temperature can indicate levels of alertness.

Body temp is less variable than heart rate.

o ~1oC drop when asleep.

GSR is a physiological response that indicates a change in the resistance of the

skin to electrical content. Measures level of sweat and hence arousal.


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SLEEP

METHODS USED TO STUDY SLEEP Can be described as a regularly occurring ASC that typically occurs

spontaneously and is characterised by a loss of consciousness.

State NWC ASC

Awareness Awareness of internal andexternal environment.

Less aware of sensations andexternal environment.

Perception and Cognitiveprocesses Perception is clear andindividuals are aware of theirthoughts.

Distortions may occur, mayalso lose touch with reality.Daydreaming: Less aware ofsensations.Meditation: Dulledperception of sensations.Alcohol-induced State: Canbe seriously dulled (vision,reaction, consequences ofactions).

Content Limitations Content can be limitedthrough selective attention.

Not as limited and less logicalDaydreaming: Less bizarre

thoughts. Selective attentionmakes you snap out of adaydream.Meditation: More limited.Focusing on one thing.Alcohol-induced State:Lowered and less restricted.

Memory The brain actively storesinformation and retrievesinformation from memory.

Continuity is disrupted withgaps or blackouts.

Time Orientation Perceived as objectivelycorrect.

Disturbed estimation mayappear faster or slower than

in reality.Emotional Awareness Individuals are aware of their

feeling and show a normalrange of appropriateemotions.

Daydreaming: Can elevate,flatten or depress mood.Meditation: Greater sense ofcontrol over emotions.Alcohol-induced State:Intensified as well as greateramounts of aggression,depression, false confidence.May misread othersemotions.

Levels of Awareness Can complete both

controlled and automaticprocesses.

Difficulty in self-control.

Daydreaming: Decreased,especially for environment.Meditation: Decreasedawareness.Alcohol-induced State: Loweredinternally and externally.


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Polysomnography is an intensive study of a sleeping person, involving

simultaneous monitoring and recording of various physiological responses.

o Self-reports can also be helpful (sleep diaries).

EEG can DARE activity brain during sleep.o Distinguish four stages of sleep.

EOG measures eye movement by DARE activity of eye muscles.

o REM and NREM.

EMG DARE activity

muscle.

o Used like EEG,

distinguish

stages.

Heart rate and core

body temperature.o Both gradually

drop as we fall

deeper in sleep.

Video monitoring and

self-reports.

CHARACTERISTICS AND

PATTERNS OF SLEEP

Non-rapid eye

movement (NREM)sleep and Rapid-eye

movement (REM) sleep.

Adults have generally have a cycle of NREM lasting 70-90 minutes with a period

of REM after every NREM period.

A sleep cycle is all 4 NREM then one REM, usually 4-5 per night.

As we grow older we progressively spend less time in REM.

o At birth it is ~50% but stabilises at about 20% for adults.

Time spent sleeping decreases.

o 17-18hrs for newborns;

o 9-10hrs for 10 year olds;o 7-8hrs for adults.

Adolescent sleep patterns also change.

o Teenagers need more sleep due to body growth and increase in

hormones etc. but often do not get this (being rebZ and school).

o ~2 hours of a change in when they become sleepy.

NREMSLEEP


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~80% of sleep is NREM, typically first half has more than the second.

EEG shows the brain is less active in NREM than REM.

When we first close our eyes we emit alpha waves (relaxation)

Transition period of awake sleep is the hypnogogic state.

o Slow rolling eye movements. Linked to physical restoration.

NREM 1

Alpha and theta waves.

Occurs as we drift in and out of sleep.

Decrease in heart rate, respiration, body temp., muscle tension.

Hypnic jerks occur.

o Muscle spasm.

NREM 2


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Mostly theta, some alpha.

Light stage of sleep, still easily aroused.

Physiological changes more than NREM 1.

Sleep spindles (brief bursts of higher frequency brain activity) occur hereperiodically for ~1 second indicates true sleep.

K-Complexes (high amp, low freq.).

NREM 3

Moderately deep sleep.

Physiology drops again.

Difficult to arouse, if so feels groggy.

Delta waves make 20-50% of waves and some theta.

o Beginning of slow wave sleep (SWS).

When EEG show >50% are delta, it is now NREM 4.

NREM 4

Delta waves and some theta.

Very deep sleep.


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Completely relaxed barely move.

Difficult to wake.

First time is up to 20 minutes then progressively less.

REMSLEEP

A period of rapid eye movement sleep during which eyeballs move rapidly

beneath eyelids.

Low amplitude, high frequency beta-like waves, similar to alert wakefulness.

Muscles are completely relaxed (Cat on slide).

Vivid dreaming.

Increase in heart rate, blood pressure, and breathing.

Paradoxical sleep as the brain and internal body are active but skeletal muscles

are completely inactive.

o Internally active, externally calm.

May be involved with consolidation of memory.

Must make up for lost REM in REM rebound.

THE PURPOSE OF SLEEP Two theories propose the purpose of sleep:

o Sleep is restorative;o Sleep is for survival.

Both can coexist.

RESTORATION

Restorative theories propose that sleep provides a time-out from activities that

use up physical and mental resources.

A period of physiological rest.

o When ill we sleep for longer;

o Growth hormones are released when asleep at a higher rate than during

NWC.

NREM and REM have different restorative effects.


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o NREM for restoring the body;

o REM for the brain as well as higher mental functions like learning and

memory.

Infants experience more REM, suggesting the mental restorative function ofsleep.

Proposed that REM allows for regular exercise to the neurons that form circuits,

promoting maintenance.

o Synapses can deteriorate if too inactive, hence more REM in infants.

REM may also assist in consolidating/embedding newly learned information by

strengthening neural connections that form when learning.

o Think of newly learned information as wet cement.

Not proven exactly what sleep specifically restores.

o If it is only restoration then inactive people should sleep less than active

people.o A lower temperature and metabolism are more linked to conservation than

restoration.

SURVIVAL

Sleep evolved to enhance survival by making us inactive during periods of

danger.

o Does not explain loss of awareness in sleep.

Based off the sleep patterns of animals.

o Larger animals tend to sleep less than smaller animals as they are

exposed. Humans are visual and require light, therefore cannot function at night.

SLEEP DEPRIVATION Going without sleep.

PARTIAL SLEEP DEPRIVATION

Decline in ability to perform cognitive tasks.

o Slower reaction times;

o Think irrationally and illogically;

o Difficulty with creative thinking.

Occurs over a relatively short amount of time with minor physiological and

psychological effects.

Quickly recover by paying off debt.

o Not all, just some.

Still, dangerous effects for many such as drivers or doctors whilst deprived.

Memory is distorted, but mainly short-term.

TOTAL SLEEP DEPRIVATION

Research relies on animals and convenience samples.

No long lasting effects and pretty much all temporary ones are repaired through

sleep.

During deprivation one may experience hallucinations, delusions or paranoia.


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Physical effects include sleepiness, lethargy, increased sensitivity to pain, slurred

speech and of course, fatigue.

o Impair immune system too (Rat deaths).

After 3-4 days ofwakefulness people

experience microsleeps.

o Very short period of

drowsiness/sleeping

whilst awake.

Usually no

recollection of

microsleep.

CENTRAL NERVOUS SYSTEM

THE BRAIN Weighs ~1.5kg.

Billions of neurons

o Trillions of connections between neurons.

Master organ.

Organised into many identifiable structures, but functions in an interrelated way.

CEREBRAL CORTEX

Involved in information-processing activities such as perception, language,

problem solving, memory, learning etc.

Is the folded outer layer of the brain.

o 2-4mm thick.

o Folded to increase its ability to fit in the skull.

Three major categories:o Sensory cortex areas.

CNS

BrainSpinalCord

NS

PNS

Autonomic NS

Sympathetic NSParasympathetic

NS

SomaticNS


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Receives and processes information from our senses.

o Motor cortex areas.

Receives processes and sends information about voluntary

movement.o Association cortex areas.

Integrates sensory, motor and other information for complex

cognitive tasks such as perception and lateral thinking.

It is believed that the size of an animals association cortex area

increases the complexity of the animal increases.

CORPUS CALLOSUM The two hemispheres of the brain do not operate independently.

o Interact and function in a coordinated way.

The corpus callosum is a band of nerve tissue connecting the left and right

hemispheres.

o Main communication pathway.

CEREBRAL HEMISPHERES

Hemispheres are almost identical brain structures separated by a deep groove.

o Not fully separated.

Contralaterally organised.o Left hemisphere receives sensory information from the right side of the

body and controls voluntary movement on the right side.

o Right hemisphere receives sensory information from the left side of the

body and controls voluntary movement on the left side of the body.

The left side is primarily involved in language.

The right side is primarily involved in non-linguistic functions.

FOUR LOBES OF THE CEREBRAL CORTEX Cortical lobes are areas of the brain associated with different functions and

structures. Within the association cortex are association areas, each one integrating

information from motor, sensory and other areas.

Sensory areas of lobes receive and process information from sensory receptors,

they are neurons specialised to detect/respond specific types of sensory

information.

o They convert raw information into impulses and transmit them to be

processed.

o Motor areas of lobes receive and process information about voluntary

movement.


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FRONTAL LOBE Largest lobe, forward half of each hemisphere.

Voluntary movement.

Personality, emotions, planning, thinking, decision-making.

The end-point for a lot of sensory information received and processed in other

lobes.

o Takes on an executive role.

Primary Motor Cortex

Responsible for controlling voluntary body movements,

Contralaterally organised. The more complex/fine the movement of the body part, the more cortical area

devoted.

Organised so that the parts at the bottom of the body are controlled at the top of

the PMC.

Brocas Area

Left frontal lobe, next to the parts of the PMC responsible for the movement of

muscles controlling speech.

Production of articulate, fluent speech.

Understanding grammar.


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PARIETAL LOBE

Upper back, behind the frontal love.

Receives and processes sensory information.

o Sends information to other areas of the brain. Has association areas that integrate information so we can perceive our position

in space (PVC and PAC) and visual attention/spatial reasoning.

Primary Somatosensory Cortex

Receives and processes sensory information from the sensory receptors in the

body, allowing us to perceive bodily sensations.

Contralaterally organised.

Areas at the bottom of the body are at the top of the PSC.

Amount of cortical area devoted is proportional to the sensitivity of the body part.

o Lips, tongue and fingers are very sensitive. Homunculus.

OCCIPITAL LOBE

Rear of each hemisphere.

Mainly concerned with vision.

Damage can cause blindness.

Association areas interact to select, organise and integrate visual information and

interpret it in a meaningful way.

Primary Visual Cortex

Base of each occipital love.

Major destination of visual information from sensory receptors on retina.

Left of each eye is the right visual field, and the right of each eye sees the left

visual field.

The right visual field is sent to the left PVC and vice versa.

TEMPORAL LOBE

Located in the lower central area of the brain.

Primarily involved in auditory perception as well as memory.

Different association areas involved with memory.

o Linking emotions with memory.

o Appropriate emotional responses to sensory information.

o Object and facial recognition.

Primary Auditory Cortex

Receives and processes sounds from both ears.

Verbal sounds are processed in the left PAC and non-verbal sounds in the right

PAC.

Different amplitude and frequencies are processes in specialled areas.


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The two major functions are to enable an organism to pay attention to sensory

stimuli then send to the relevant part of the cerebral cortex.

SPINAL CORD Column of nerve fibres that extends from the base of the brain to the lower back.

Receives sensory information from the PNS and sends to the brain.

Receives information from the brain and relays it to muscles glands and organs

for control of them.

SPECIFICDAMAGE

Damage to areas can lead to a loss of them functioning.

Aphasia refers to a language disorder apparent in speech, writing or reading,

produced by an injury to the brain area specialised in that function.

o

Not due to a loss of sense or lack of intelligence.

Brocas Aphasia

Non-fluent aphasia.

Characterised by a difficulty speaking despite understanding speech.

Speak short deliberate sentences with pauses.

Complicated syntax can confuse aphasics.

Damage to the Brocas area.

Self-aware

Wernickes Aphasia

Fluent aphasia.

Considerable difficulty comprehending speech and speaking in am meaningful

way.

o Speech is fluent but nonsensical.

o Word salad.

Little or no conscious awareness.

Damage to Wernickes area.

Spatial Neglect

An attentional disorder where individuals fail to notice anything on the right or left

side of the world/body.

o The other side does not exist.

Mostly the left side due to damage in the right parietal lobe.

Mostly visual but possibly other senses or a combination.

Can impair recall of images from memory but not memory impairment.

Severity can range. Failure or attention.


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SPLIT-BRAIN STUDIES In epilepsy the electrical activity spreads through the brain.

A split-brain surgery involves surgically removing the corpus callosum.

Cat experiment (Sperry&Myers)

o Taught with an eye blocked and timed how long it took to relearn.

Sperry&Gazaniga

o Test the ability of split-brain patients against those without the

disconnection.

o Visual information is flashed on a screen.

o If visual information from the right hemisphere cannot cross to the left

hemisphere (language) then they cannot say what they saw.

o Right side could control the left hand to find what was seen.

Gives evidence of specialised functions of hemispheres.

You can still function as

a) The two

hemispheres can

compensate for the

loss

b) Some nerve fibres

are still intact.

PERCEPTUALANOMALIES Perception is the meaningful

interpretation of sensory

information and stimuli.

A perceptual anomaly refers to when perception is irregular, it can occur with all

senses.

MOTION-AFTEREFFECT Perceptual illusion of movement on a stationary stimulus following exposure to

motion.

Waterfall effect.

Opposite direction.

Possible cause is that specific neurons are fatigued by constant movement

whilst those neurons not sensitive are still active.

o Neural adaption.

Exact cause is unknown.

CHANGE

BLINDNESS

Difficulty observers have in noticing large changes to visual scenes.


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o Both when expected and unexpected.

o Disruption in the continuity of the scene.

Thalamus plays a role focused attention to detect change.

Different from inattential blindness, which is failing to notice something in fullsight.

Aware of a change but not sure what changed.

Attentional capacity for ST visual memory is very limited

SYNAESTHESIA

Perceptual experience where the stimulation of one sense produces an addition

response in another sense, adding but not detracting from the original.

Involuntary and hard to suppress.

One-way.

~1 in 2000 is the accepted figure. Stroop effect task can help to show.

Possible causes are that:

o Synesthetes are unusually sensitive to external stimuli

o Ay be due to a breakdown in sensory and perceptual processes

o Excess neural connection

PERIPHERAL NERVOUS SYSTEM

CNS

BrainSpinalCord

NS

PNS

Autonomic NS

Sympathetic NSParasympathetic

NS

SomaticNS


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MEMORY Without memory, learning would not be possible.

Memory is defined as the storage and retrieval of information acquired through

learning.

Three fundamental processes:

1. Encoding the process of converting information into a usable form so it

can be stored in memory.

2. Storage is the retention of information over time.

Memories are stored representations of information.


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We ignore most of the information that enters sensory memory but if we attend to

it is transferred to STM.

Decays rapidly.

May act as a filter.

ICONICMEMORY

Used to describe visual sensory memory.

Retained just long enough to be recognised and processed.

Has a potentially unlimited storage capacity.

Usually retains just the last visual image.

Can hold information for 0.2-0.4s

ECHOICMEMORY

Used to describe auditory sensory memory. Sounds linger like an echo.

Holds information for about 3-4s.

o Important for understanding speech.

o Retains the last few sounds.

SHORT-TERM MEMORY (STM) A memory system with a limited storage capacity in which memory is stored for a

relatively short time unless renewed.

Lasts longer than sensory memory.

Information is an encoding of the sensory information. Can hold info for about 20s, but it starts to decay after ~12s.

Has a capacity of about pieces of information.

o When full new information pushes out old info.

o Space filled by thinking or retrieving info from LTM.

Lost primarily through decay or displacement.

WORKING MEMORY

Used to emphasise the active part of memory where information is worked on.

Sensory information is processed here and LTM info is manipulated her.

Temporary storage facility/mental workspace for info used by current cognitiveactivity.

Only remains here as it is processed/manipulated/examined.

CHUNKING INFORMATION

Combining smaller bits of information into larger single units.

Increases the capacity of information in STM.

o 4, 5, 6 become 456.

REHEARSAL

Process of consciously manipulating information to keep it in STM or transfer it to

LTM.


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Proposes that information in LTM is organised systematically in overlapping

networks of interrelated concepts.

Activation of one node causes other related nodes to be activated.

Information is not doubled up. Spreading activation is that activating one node makes the activation of another

node more likely to be activated.

SERIAL POSITIONEFFECT

Free recall is better for items at the

beginning and end of a list than in the

middle.

The Primacy effect (remembering those

at the start of a list) is due to them being

rehearsed more and transferred to LTM.

The recency effect (those at the end) is

due to those items stored in STM.

The items in the middle were said too

early for STM and too late for LTM.

ROLE OF THE NEURONKANDEL Eric Richard Kandel researched theAplysia.

o They only have ~20 000 neurons whilst humans have billions.

o Kandel would stimulate theAplysias siphon.

It would retract gills as a reflex action.

o The mollusc learnt that there was no need to retract the gills through

habituation.

By activating the reflex over and over the synapses between

neurons were strengthened.

Decided that the nervous system of organisms learn in a similar manner.

Memory is formed through biochemical and physiological changes in neurons.

ROLE OF THE HIPPOCAMPUS AND TEMPORAL LOBE The hippocampus is a structure in the temporal love associated with encoding

information and transferring it from STM to LTM.


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AMNESIA RESULTING FROM BRAIN TRAUMA OR DEGENERATIVE DISEASES Brain trauma is an umbrella term regarding any brain damage that interferes with

the normal functioning of the brain.

Neurodegenerative diseases are characterised by a progressive decline in the

functioning, structure or activity of brain tissue.

o Typically age related.

AMNESIA

Amnesia refers to a loss of memory.

o Period of time forgotten generally shrinks over time.

Time just before the damage usually always forgotten.

Retrograde amnesia is a loss of memory of events before the person sustained

damage.

o Recovery may be initially rapid then slowed. Anterograde amnesia is an inability to form memories after the damage is

sustained.

Korsakoffs syndrome is a neurodegenerative disease where severe memory

damage is related to damage to parts of the brain related to memory.

o Vitamin B deficiency.

o Alcoholics commonly get it due to a poor diet.

DEMENTIA

Refers to a large group of neurodegenerative diseases causing a decline in

mental functioning. Final stages of dementia can have people shutting themselves out of the outside

world.

Alzheimers disease is caused by a widespread degeneration of brain neurons.

o Resulting in a loss of memory and cognitive/personality changes.

4th largest cause of death in Australia.

o Loss of knowledge, awareness of events, words and names, directions or

skills.

o Change in personality.

o High levels of amyloid in the brain.

Hippocampus is most affected.


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5151Psychology Unit Three Notes Burbs