Psych1101

Phrenology

Study of shape and size of the cranium as a supposed indication of character and mental abilities. Popular in 19th century

Behaviourism

Emphasises environmental control of behaviour through learning. Pavlov (classical conditioning), Skinner (Operant conditioning), Thorndike (law of effect)

Psychodynamic theory (Freud)

emphasises dynamic relations between conscious and unconscious motivation.

Id (freud psychdynamic)

Is the unconscious reservoir of libido, fuels instinct

Ego (freud psychodynamic)

The general manager of personality, makes decisions

Superego (freud psychdynamic)

The repository of a individuals moral values (the whole iceberg)

Cognitive Psychology

Study of how mental processes influence behaviour, sees brain as information processor

Biological Perspective

How brain processes and other bodily functions regulate behaviour

Neurotransmitters

Chemicals that allow nerve cells to communicate with one another

Experimental research

Researcher manipulates more then one variable, researcher measures whether this manipulation influences other variables, researcher attempts to control extraneous factors.

Non Associative learning

Habituation and Sensitisation

Habituation

Response to stimulus decreases with frequent presentation

Sensitisation

Response to stimulus increases with frequent presentation

Classical conditioning

Organism learns to associate two stimuli so one stimulus elicits a reflexive response that was originally only elicited by the other stimulus.

Unconditioned stimulus

Thing that naturally causes the reflexive response

Unconditioned response

Natural reflexive response

Conditioned stimulus

Previously neutral thing that has been conditioned to cause reflexive response

Conditioned response

Conditioned reflexive response

Acquisition

pairing the UCS and UCR to become CS

Operant Conditioning

Voluntary behaviour is influenced by the consequences that follow it

Shaping

Rewarding successive approximations of the target behaviour, useful to build a new behaviour or skill.

Chaining

Linking sequences of a behaviour. Each step reinforced by the opportunity to do the next step

Behavioural genetics

Study of how genes and environment interact with each other to influence psychological characteristics

Genotype

Genetic makeup of an individual

Phenotype

Individuals observable traits

Genome

Complete sequence of genetic material

Genome Wide association studies (GWAS)

Look for variations in DNA that are correlated with a trait

Concordance

Probability that a pair of individuals will show a trait, given that one of the pair shows the trait

Heritability

Extent to which the differences in a trait can be attributed to genetic differences. Is specific to the group and environment studied (within group)

Genetic influences on environment

passive (parents pass on genes then create a shared environment that is influenced by their genetic traits), evocative (A childs genetically influenced traits evoke certain responses from others), active (individuals seek environments compatible with genetically influenced traits)

Environmental influence on genetics

Epigenetic (gene expression can be altered by non-genetic factors, alters the phenotype not the genotype), reaction range (Genes allow for potential outcomes, environment determines the actual outcome)

Alzheimer’s disease

Accumulation of harmful proteins in the brain that causes dementia. Dementia risk is influenced by complex interactions between many different genes and environmental factors.

Determinism

Idea that a behaviour is determined. Casual inevitability e.g. if you have this gene you WILL act agressively. Behavioural and Genetic determinism believe that behaviour is product of environment / genes. This overlooks complex interactions between genes and environment.

3 Misconceptions of behavioural genetics

Correlation doesn’t equal causation, Even a trait with 100% heritability can be modifiable by environmental factors, Heritability is a measure of correlation not causation. These are the correct things, people usually get these the wrong way round.

Brain Gross Structure

2 Asymmetric hemispheres connected by corpus callosum. Frontal, Parietal, temporal, occipital lobes.

Brain Cells

Consist of neurons and glial cells. Neurons process info, glial cells provide physical structure and support functions.

Cell body (soma)

Common to all cells, contains nucleus and all structures necessary for cell functioning

Dendrites

Unique neuronal structure. Receive ‘input’ signals from other neurons.

Axons

Unique neuronal structure. Sends ‘output’ signals to other neurons.

How neurons communicate

Fatty cell wall regulates ion flow creating a resting membrane potential. Meaning a voltage difference between the inside and outside of the neuron of about -70 millivolts. Then excitatory and inhibitory messages from other neurons change resting potential. If enough excitatory messages are received, resting potential will exceed threshold. This then initiates a rapid depolarisation at the axon hillock which creates a current that moves down the axon. This current is called the action potential. But because axon isnt permeable to ions, initial action potential isnt strong enough to travel down axon. The myelin sheath helps this. Arrival of action potential at presynaptic axon terminal triggers the release of neurotransmitters. Neurotransmitters enter synaptic cleft and dissipate through the cerebrospinal fluid, with some binding to receptors on dendrites of adjacent neurons. Can either depolarise or polarise the post synaptic neuron.

Prefrontal cortex

Planning, inhibition, working memory

Motor cortex

Planning movements, selection of physical movements to accomplish plan and coordination of movements including hands.

Somatosensory cortex

Pressure, pain, temperature, proprioception.

Visual cortex

Form, Motion, line orientation, colour, object identity

Auditory cortex

sound frequency, sound location, music, language, prosody

Hindbrain (cerebellum)

Stores procedural memories, helps co-ordinate complex movements. Regulates breathing, basic autonomic functions, sleep/wakefullness

Inattentional blindness

Failure to see something we’re looking at, often because attention is preoccupied

Change blindness

We’re very bad at noticing large changes, failure to update representations between views

Top-down attention

Voluntary, purposeful, strategic directing of attention

Bottom-up attention

Reflexive, some things seem to grab attention on their own

Atkinson & Shiffrin three stage model of memory

Sensory memory; brief high capacity representation of what is being sensed. Can be Iconic (visual), echoic (auditory)

Working memory: Limited capacity system that temporarily stores and processes information. Information will last about 20-30 seconds if not actively/used processed.

Long term memory: No known capacity

Types of memory

Explicit memory: Requires conscious or intentional memory retrieval

Declarative: Involves factual knowledge and includes two subcategories, episodic (personal experiences), semantic (general factual knowledge)

Implicit: Memory that influences our behaviour without conscious awareness

Procedural: Involves skills and actions and classical conditioned responses

Depth of processing

Information with personal meaning and distinctive properties are also better remembered. When encoding and retrieval values match it is more beneficial. State, mood and surrounding environment can serve as retrieval cues.

Amnesia

Retrograde: Memory loss for events that took place before the onset of amnesia

Anterograde: Memory loss for events that occur after the onset of amnesia

Neurodegeneration

Dementia: Impaired memory and other cognitive deficits that accompany brain degeneration and interfere with normal functioning

Alzhiemer’s disease: Progressive brain disorder that is the most common cause of dementia

Schemas

Mental framework to group concepts, help us perceive, organise, process and use information. Based on experiences and expertise. Lead us to encode or retrieve information in ways that fit in with our pre-existing assumptions.

Heuristics

‘Rule of thumb’ that enable us to make fast judgements based on partial data. Are intuitive and efficient, but subject to bias and failure.

Availability: Make decisions based on which instances come to mind.

Recognition: Infer that the recognised objects have higher value than those that aren’t recognised.

Anchoring and adjustment: Rely on the first piece of information and adjust from there.

Photoreceptors

Convert light wave energy into neural signal.

Cones: work in good lighting and are sensitive to fine detail and colour. Predominantly found at the fovea.

Rods: Work in dim lighting and are sensitive to movement but not fine detail or colour. Found in the periphery

Colour contrast

Shows that the colour we perceive is influenced by its surroundings.

Colour constancy

Tendency of a surface to appear the same colour under a fairly wide range of illuminants

reconstructing a unified holistic perception

Rules governing the types of visual cues that are linked and those that are dissociated. Important first stage in scene processing is to organise images into figures of interest and background.

Gestalt principles: Similarity, proximity, closure, continuity

Linear perspective

Lines that are parallel in 3D world will appear to converge in 2D image as they extend in the distance

Interposition

Cue to relative depth order in which, for example, one object obstructs the view of part of another object

Relative height

Below the horizon, objects in the visual field appear to be further away. Above the horizon, objects lower in the visual field appear to be farther away

Relative size

Comparison of size between items without knowing the absolute size of either one. We assume that smaller objects are further away.

Motion parallax

Images closer to the observer move faster across the visual field than images farther away.

Audition

Works in frequency and amplitude of sound waves. Frequency is the number of sound waves, or cycles per second. Amplitude is a measure of the physical pressures that occur at the eardrum

Frequency theory: We sense sound frequency depending on the fluid movement

Place theory: Sense sound frequency according to the locations of fluid activity in the cochlear

Semi circular canals

Lie on distinct planes, give us sensation associated with up, down, left and right movements.

Analgesia

Decreasing pain sensitisation during conscious experience

Endorphins

Neurotransmitters associated with pain inhibition.

Phantom limb

Sensation perceived from a physically amputated limb of the body

Motivation: Evolution - Instincts

inherited, common to a species, automatic fixed action pattern. Adaptive significance.

Motivation: Evolution - Genes

Now study genetics that might underlie ‘hard-wired’ mechanisms of behaviour. Genetically based predispositions to act a certain way.

Motivation: Biological - Homeostasis

Aim to maintain internal physiological equilibrium. Requires a sensory mechanism, a response system and a control centre

Motivation: Biological - Drives

Deficits create drives, Motivate us reduce deficits and restore homeostasis

Motivation: Brain and learning

Behavioural activation system; Activated by signals of potential reward and gratification of needs. Produces movement toward positive goals in anticipation of pleasure. Behavioural inhibition system, opposite, produces fear and avoidant behaviours

Four features of emotional states

Cognitive appraisal, physiological response, instrumental behaviours, expressive behaviours

Theories of hypnosis

Disassociation theories: as an altered state involving a division of consciousness.

Social-cognitive theories: Experience results from expectation of people who are motivated to take on role of being hypnotised

EEG signals when awake

Beta waves present when alert, alpha waves present when drowsy and relaxed.

REM sleep

rapid eye movements, high arousal and frequent dreaming, considered paradoxical sleep as high arousal but little movement.

Dream theories

Freud psychoanalytic: Wish fulfilment

Cognitive theories: Problem solving

Activation synthesis theory: random