Chapter One- Introduction to Cognitive Psychology

Transcription

1 Chapter One- Introduction to Cognitive Psychology -Concerned with the scientific study of the mind and how the brain processes information -The mind creates and control mental capacities such as perception, attention and memory and creates representations of the world that enable us to function Wundt s Psychology Laboratory: Structuralism and Analytic Introspection -The first laboratory of scientific psychology which was concerned with the mind. Introspection: Asking people to look at something and interpret/explain how Structuralism: Explained perception as the adding up of small elementary units called sensations. Analytic introspection: participants described their experiences and thought processes obtained by stimuli under controlled conditions Fechner: Relationship between stimulus and our perception of it (not 1:1...need larger increase before we notice it. 20 th C Watson -founded behaviourism, particularly in relation to structuralism -Procedures were based on classical conditioning -Behaviourism was measured by observation -Invisible mental processes were seen as not valid 1930 s-1940 s Skinner -Operant conditioning, which assured that behaviourism would be the dominant force in psychology in the 1950 s 1950 s Cognitive revolution -A decline in the influence of behaviourism and re-emergence of the study of the mind Chomsky -critique of Skinners Book -language system has unlimited abilities -Karl popper: falsifiability (test predictions even if cant see) -Introduction of the digital computer and idea that the mind processes things like a computer -Cherry s attention experiments -Broadbent s introduction of flow diagrams to illustrate the processes involved in attention -Interdisciplinary conferences Information processing approach: The mind is described as processing information through a sequence of stages Artificial intelligence: The ability of a computer to perform tasks associated with human intelligence Logic theorists: Computer program devised by Newell and Simon that was able to solve logic problems Donders Pioneering Experiment: How long does it take to make a decision -Measured reaction time by seeing how long it takes one to respond to a stimulus. Simple reaction time: Reacting to the presence or absence of a single stimuli (as opposed to having to choose between a number of stimuli)

2 Choice reaction time: Reacting to one or two or more stimuli. One response to one stimuli and another response to the other. Ebinghaus s Memory Experiment: What is the Time course of Forgetting? Savings method: Method to measure retention in memory experiments. Read a lists of nonsense syllables and determined how many repetitions it took to repeat the lists with no errors. He then repeated this after various intervals and compared the number of repetitions needed for no errors. Other: Memory consolidation -illustrated how answering one question can lead to many additional questions and how psychologists can study the mind by using both behavioural and physiological approaches Miller-Short term memory -how much and how long you can retain something -7 + or 2 Sperling-Memory capacity -Why is memory capacity limited?

3 Chapter 2-Cognitive Neuroscience -Ramon Cajal s research resukted in the abandonment of the neural net theory in favour of the neuron doctrine. -Signals can be recorded from neurons using microelecrodes. Reception: Absorption of energy by sensory receptors (end point of the brain) Transduction: Transformation of energy in to neural energy (firing neurons/action potentials) Coding: Includes which neurons are firing, how many (the more intense a stimulus the more neurons), changes in firing rate and patterns. Detecting stimulus intensity: The more intense a stimulus, the more neurons and the faster they will fire. Detecting Pitch: fractionation (only respond as a certain frequency/change) Modality: Distinct -Labelled line ( eye to visual centre of brain) Rods: 120 million, Low light, pick up movement Cones: 6 million, daylight, detail and colour Two visual pathways Parvocellular: Cones, high light, colour Magnocellular: Nighttime, rods, low light, movement Action Potential: Electrical potential that traves down a neurons axon Distributed coding: Representation of an object or experience by the pattern of firing and number of neurons Distributed processing: processing that involves a number of areas of the brain Event-related potential: A potential recorded with disc electrodes on a person s scalp that reflects the response of many thousands of neurons near the electrode that fire together. Functional magnetic resonance imaging: Brain imaging technique that measures how blood flow changes in response to cognitive activity. Dendrites: Structures that branch out from the cell body to receive electrical signals from other neurons Nerve net: A network of continuously interconnected nerve fibres Neuron doctrine: The idea that neurons transmit signal in the nervous system and that these cells are not continuous with other cells. Microelectrode: Small wires which are used to record electrical signals from neurons. Recording electrode: Thin metal probe that can pick up electrical signals from neurons Reference electrode: used with recording electrode to measure the difference in charge between the two Somatosensation: Touch Parahippocampal place area: Area in the temporal lobe that contains neurons that are activated by pictures of indoor and outdoor scenes. Positron emission tomography: Technique which involves the injection of a radioactive tracer. Extrastriate body area: An area of the temporal cortex that is activated by pictures of bodies and body parts but not by faces and other objects. Fusiform face area: The area of the temporal lobe which contains many neurons that respond selectively to

4 faces. Grandmother cell: A neuron that only responds to a highly specific stimulus. Could be an image of someone s grandmother etc. Temporal Lobe: Responsible for Language, memory, hearing and vision Paretial lobe: Responsible for sensations caused by stimulation of the skin and some visual aspects Occipital lobe: Analyses incoming visual information Frontal lobe: Higher functions such as language, memory, thought and motor functioning. Broca s Area: Frontal lobe associated with the production of language Broca s Aphasia: Difficulty using speech to express thoughts but can still understand speech Werinickes area: Temporal Lobe, associated with understanding language Wernicke s aphasia: Difficulty understanding language, can speak but can be jumbled Prosopagnosia: Damage to the temporal lobe, inability to recognise faces Synaesthesia: -No cleanr distinction between modalities -Colour, taste, touch, vision -Less Neural pruning than a norma person -Hereditary -Females more than males -Stable over time

5 Chapter 3-Perception -Our experience of the world is (idiosyncratic) individual Binocular cues -Dont need experience -Develop with maturation -Useful for close range Monocular Cues -Experience needed -Require information from only one eye -Used in painting (More detail, texture etc) Bottom-up processing (Innate) -Processing that starts with information received by the receptors. -Feature detection and intergration -Neurons respond best to simple shapes with specific orientations -Extension of sensation -Identify features and compare to memory Top-Down Processing (Learnt) -Context and expectation facilitates perception -Exact same stimulus, however see differently due to surrounding context -Visual illusions are due to failure of top down processing Recognition by components: Recognition of objects is based on 3D features called geons. Geon: Basic 3D volumes. Basic unit of object perception. Componential recovery: If we can see an object geons we can recognise it Aquired Prosopagnosia: Brain damage (Inability to recognise faces) Congenital Prosopagnosia: From birth Visual Agnosia - Damage to cortex at occipital temporal border -Cant recognise or identify objects (Can use other senses to recognise) Gestalt psychologists: Proposed principles governing perception such as laws of organization and the perceptual approach to problem solving. -Learn cues from the environment -Requires experience Theory of natural selection (Darwin): Genetically based characteristics that enhance an animals ability to survive will be passed down when animals reproduce Law of perceptual organization: How small elements of a scene become grouped to form larger objects/units. (a.k.a heuristics) Heuristic: Best guess solution to problems Algorithm: A procedure that is guaranteed to solve a problem