Active - perception Perception as a function of interaction with the world.
Affordances - Represent the interaction of the individual with the environment. Objects afford the use to which the individual can put them.
Agnosia - The failure to recognise or interpret stimuli despite adequate sensory function. It is usually classified by sensory modality, so visual agnosia is the failure to recognise objects that are seen.
Alexia/dyslexia - Both refer to problems in reading written language. Alexia always refers to acquired difficulties in reading, while dyslexia is used to refer to developmental difficulties in reading. However some specific acquired reading problems – e.g. deep versus surface dyslexia – are used to refer to particular profiles of acquired reading problems.
Alzheimer’s disease (AD) - A degenerative brain disorder usually (but not always) afflicting the elderly, which first appears as an impairment of memory but later develops into a more general dementia.
Amnesia - A pathological impairment of memory function.
Anterograde amnesia (AA) - Impaired memory for events which have occurred since the onset of the disorder (contrasts with retrograde amnesia).
Aphasia - An acquired language disorder, which primarily affects the comprehension of spoken language (a receptive aphasia), or the production of spoken language (expressive aphasia). In global aphasia, both speech production and perception are compromised.
Articulatory suppression - A task used to occupy the articulatory control process of the working memory, normally involving the repetition of a sound (such as ‘the’) which requires articulation but little processing.
Attention conspicuity - The interaction of aspects of a stimulus (such as colour, luminance, form) with aspects of an individual (such as attention, knowledge, preconceptions) that determine how likely a stimulus is to be consciously perceived. (See also sensory conspicuity.)
Automatic processing - Processing that does not demand attention. It is not capacity limited or resource limited, and is not available for conscious inspection (contrasts with controlled processing).
Availability heuristic - Making judgements on the basis of how available relevant examples are in our memory store.
Base - rate fallacy Ignoring information about the base rate in light of other information.
Behaviourism - An approach to psychology which constrains psychologists to the investigation of externally observable behaviour, and rejects any consideration of inner mental processes.
Binaural cues - Cues that rely on comparing the input to both ears, as for example in judging sound direction.
Binding problem - The problem of how different properties of an item are correctly put together, or bound, into the correct combination.
Blindsight - The ability of some functionally blind patients to detect visual stimuli at an unconscious level, despite having no conscious awareness of seeing them. Usually observed in patients with occipital lobe lesions.
Boston Aphasia Classification System - A systematic classification of aphasic profiles which can be used to identify aphasia and to predict what profiles of damage a patients might be expected to show when assessing their damage. The Boston Classification System builds on the models of aphasia which were developed by Broca, Wernicke and Lichtheim. Implicit in this approach is the concept that language can be localised in the human brain, and that different profiles of language deficits are related to distinctly different patterns of brain damage.
Bottleneck - The point in processing where parallel processing becomes serial.
Bottom-up (or stimulus-driven) processing - Processing which is directed by information contained within the stimulus (contrasts with top-down processing).
Breakthrough - The ability of information to capture conscious awareness despite being unattended. Usually used with respect to the unattended channel in dichotic listening experiments.
Broca’s area - A region of the brain normally located in the left frontal region, which controls motor speech production.
Capture - The ability of one source of information to take processing priority from another. For example the sudden onset of novel information within a modality such as an apple falling may interrupt ongoing attentional processing.
Cell assembly - A group of cells which have become linked to one another to form a single functional network. Proposed by Hebb as a possible biological mechanism underlying the representation and storage of a memory trace.
Central executive - A hypothetical mechanism which is believed to be in overall control of the working memory. It is assumed to control a variety of tasks, such as decision-making, problem-solving and selective attention.
Cognitive interview - An approach to interviewing eyewitnesses which makes use of the findings of cognitive psychology, such as context reinstatement.
Cognitive neuropsychology - The study of the brain activities underlying cognitive processes, often by investigating cognitive impairment in brain-damaged patients.
Cognitive neuroscience - The investigation of human cognition by relating it to brain structure and function, normally obtained from brain-imaging techniques.
Cognitive psychology - The study of the way in which the brain processes information. It includes the mental processes involved in perception, learning and memory storage, thinking and language.
Comprehension - Refers to the outcome of a range of linguistic processes, from acoustic to semantic and syntactic, which contribute to the way that a linguistic message is understood.
Computer modelling - The simulation of human cognitive processes by computer. Often used as a method of testing the feasibility of an information-processing mechanism.
Confabulation - The reporting of memories which are incorrect and apparently fabricated, but which the patient believes to be true.
Congenital prosopagnosia - This is thought to be present from birth and is thought to occur without any apparent brain injury.
Conjunction - A term from feature integration theory of attention that describes a target defined by at least two separable features, such as a red O amongst green O’s and red T’s.
Consistent mapping - A task in which distractors are never targets and targets are never distracters, so that there is a consistent relationship between the stimuli and the responses to be made to them.
Constancy - The ability to perceive constant objects in the world despite continual changes in viewing conditions.
Constructivist approach - Building up our perception of the world from incomplete sensory input. (See also perceptual hypotheses.)
Contention scheduler - A component of Norman and Shallice’s (1986) model which is responsible for the semi-automatic control of schema activation to ensure that schema run off in an orderly way.
Controlled attention - Attention processing that is under conscious, intentional control. It requires attentional resources, or capacity, and is subject to interference.
Controlled processing - Processing that is under conscious control, and which is a relatively slow, voluntary process (contrasts with automatic processing).
Covert attentional orienting - Orienting attention without making any movement of the eyes.
Decision-making - This involves making a selection from various options, often in the absence of full information.
Declarative memory - Memory which can be reported in a deliberate and conscious way (contrasts with procedural memory).
Deductive reasoning - An approach to reasoning in which conclusions can be judged valid or invalid given that certain statements or premises are assumed to be true.
Deductive reasoning task - A problem that has a well-defined structure in a system of formal logic where the conclusion is certain.
Dementia - A persistent impairment in intellectual function due to brain dysfunction, which commonly is associated with a progressive loss of function. It is mainly a disease of ageing, being more common in more elderly populations. Dementias can be relatively focal in their effects (e.g. semantic dementia) or more widespread and ‘global’ in their effects (e.g. Alzheimer’s disease). Some dementias primarily affect subcortical regions (e.g. Parkinson’s disease) and other have a more cortical effect (e.g. Pick’s disease).
Developmental prosopagnosia - This is thought to be a result of early neurological trauma that might be caused by accident or injury
Diencephalon - A brain structure which includes the thalamus and hypothalamus. Parts of the diencephalon are involved in processing and retrieving memories, and damage to these structures can cause amnesia.
Digit span - A measure of the largest number of digits which an individual can recall when tested immediately after their presentation. Widely used as a test of the capacity of the phonological component of the working memory.
Direct perception - Perception without the need for top-down processing.
Disinhibition - Impaired response inhibition, an inability to suppress previous incorrect responses observed in patients with frontal lobe epilepsy.
Dorsal stream - A pathway which carries visual information about the spatial location of an object.
Double dissociation - A method of distinguishing between two functions whereby each can be separately affected or impaired by some external factor without the other function being affected, thus providing particularly convincing evidence for the independence of the two functions.
Dysexecutive syndrome - A collection of deficits observed in frontal lobe patients which may include impaired concentration, impaired concept formation, disinhibition, inflexibility, perseveration, impaired cognitive estimation and impaired strategy formation.
Dyslexia - Developmental difficulties in reading. (See also alexia.)
Early selection - Selective attention that operates on the physical information available from early perceptual analysis.
Easterbrook’s hypothesis - The notion that high levels of arousal or anxiety cause a narrowing of attention.
Ecological validity - The extent to which findings in psychology (especially those obtained in the laboratory) generalise to the real world.
Electroconvulsive therapy (ECT) - A treatment used to alleviate depression which involves passing an electric current through the front of the patient’s head.
Electroencephalography (EEG) - Recording the brain’s electrical activity via electrodes placed against the scalp. Can be used to continuously record rhythmic patterns in brain function or particular responses to events (event-related potentials).
Encoding - The process of transforming a sensory stimulus into a memory trace.
Encoding specificity principle (ESP -) The theory that retrieval cues will only be successful in accessing a memory trace if they contain some of the same items of information which were stored with the original trace.
Endogenous attention - Attention that is controlled by the intention of a participant.
Episodic buffer - A hypothetical component of working memory which integrates information from different sense modalities, and provides a link with the long-term memory.
Episodic memory -Memory for specific episodes and events from personal experience, occurring in a particular context of time and place (contrasts with semantic memory).
Event-related potentials (ERP) - Systematic changes in the brain’s electrical responses linked to the presentation of a stimulus. Typically the stimulus is presented numerous times with the electroencephalographic (EEG) signals time-locked to its occurrence then being averaged to separate the signal from noise.
Executive functions - Meta-abilities necessary for appropriate social functioning and everyday problem-solving, for example the deployment of attention, self-regulation, insight, planning and goal-directed behaviour.
Exogenous attention - Attention that is drawn automatically to a stimulus without the intention of the participant. Processing by exogenous attention cannot be ignored.
Experimental psychology - The scientific testing of psychological processes in human and animal subjects.
Explicit memory - Memory which a subject is able to report consciously and deliberately (contrasts with implicit memory).
Extended hippocampal complex - A system of interconnected structures within the brain, incorporating the hippocampus, anterior thalamus and mammillary bodies, which is involved in the encoding and storage of new memory traces.
Familiarity - The recognition of an item as one that has been encountered on some previous occasion.
Feature detectors - Mechanisms in an information-processing device (such as a brain or a computer) which respond to specific features in a pattern of stimulation, such as lines or corners.
Feature overlap - The extent to which features of the memory trace stored at input match those available in the retrieval cues. According to the encoding specificity principle (ESP), successful retrieval requires extensive feature overlap.
Features - Elements of a scene that can be extracted and then used to build up a perception of the scene as a whole. (See also geons.)
Fixation - When the fovea of the eye dwells on a location in visual space, during which time information is collected.
Flashbulb memory - A subject’s recollection of details of what they were doing at the time of some major news event or dramatic incident.
Form agnosia - This is now the generally accepted term for patients who are unable to discriminate between objects and are unable to copy line drawings of objects (this was previously termed apperceptive agnosia).
Formants - Spectral prominences in spoken language, specific patterns of which are associated with particular speech sounds – thus vowels in English are different in how the formants are spaced across the frequency range.
Frontal lobe syndrome - The pattern of deficits exhibited by patients with damage to the frontal lobes. These patients are distractible, have difficulty setting, maintaining and changing behavioural goals, and are poor at planning sequences of actions.
Functional fixedness - The inability to use an object appropriately in a given situation because of prior experience of using the object in a different way.
Functional magnetic resonance imaging (fMRI) - A medical imaging technology that uses very strong magnetic fields to measure changes in the oxygenation of the blood in the brain and thus map levels of activity in the brain. It produces anatomical images of extremely high resolution.
Fusiform face area (FFA) - The fusiform area has been shown to be a key structure in face and object processing; numerous studies have shown that the fusiform gyrus contains an area dedicated to face processing – the fusiform face area (FFA).
Galvanic skin response A measurable change in the electrical conductivity of the skin when emotionally significant stimuli are presented. Often used to detect the unconscious processing of stimuli.
Gaze-mediated orienting - An exogenous shift of attention following the direction of gaze of a face presented at fixation.
Geons - Basically features, but conceived explicitly as being 3-D features.
Gestalt psychology - An approach to psychology which emphasised the way in which the components of perceptual input became grouped and integrated into patterns and whole figures.
Gyrus - The surface of the brain is formed by the cerebral cortex, and this has its surface area greatly increased by being thrown into folds. A gyrus is the outer surface of one of these folds, and a sulcus is formed when in the depths of a fold. If the fold in the cortex is very deep it is called a fissure, like the lateral fissure which separates the temporal lobe from the frontal lobe.
Haptic perception - Tactile (touch) and kinaesthetic (awareness of position and movement of joints and muscles) perception.
Herpes simplex encephalitis (HSE) - A virus infection of the brain, which in some cases leaves the patient severely amnesic.
Heuristics - Methods or strategies which often lead to problem solution but are not guaranteed to succeed.
Hippocampus - A structure lying within the temporal lobes, which is involved in the creation of new memories. Hippocampal lesions usually cause impairment of memory, especially the storage of new memories.
Ideomotor compatibility - The compatibility between the stimulus and its required response in terms of, usually, spatial relations.
Illusions - Cases in which perception of the world is distorted in some way.
Impasse - A sort of mental ‘blank’ experienced when trying to solve a problem, which is accompanied by a subjective feeling of not knowing what to do.
Implicit memory - Memory whose influence can be detected by some indirect test of task performance, but which the subject is unable to report deliberately and consciously (contrasts with explicit memory).
Individuation - Recognising one specific item from other members of that class of item (e.g. recognising the face of a particular individual).
Inductive reasoning task - A problem that has a well-defined structure in a system of formal logic where the conclusion is highly probable but not necessarily true.
Insight - The reorganising or restructuring of the elements of the problem situation in such a way as to provide a solution. Also known as productive thinking.
Integrative agnosia - This is the generally accepted term for associative agnosia. It refers to patients who can perceive the individual shapes and elements of objects but are unable to integrate these into a representation of the whole object.
Interpolation - Using computerised image-processing systems to construct images that are intermediate between two other images.
Judgement - This involves an assessment of the likelihood of an event occurring on the basis of incomplete information; it often forms the initial process in decision-making.
Knowledge - Information that is not contained within the sensory stimulus.
Korsakoff’s syndrome - A brain disease which usually results from chronic alcoholism, and which is mainly characterised by a memory impairment.
Late selection - An account of selective processing where attention operates after all stimuli have been analysed for their semantic properties.
Laws of perceptual organisation - Principles (such as proximity) by which parts of a visual scene can be resolved into different objects.
Lesion - Refers to tissue damage – in the brain this can be a result of a stroke, a tumour, an infectious disease, the effects of a toxin, a direct injury or a progressive disease (a dementia).
Lexical decision task - An experiment in which participants are given a target item (typically written), and asked to decide whether it is a real word or not. Lexical decision tasks are used as the amount of time taken to give a response can indicate how the target item is being processed: this response can be used in combination with other tasks, e.g. priming.
Long-term memory - Memory held in permanent storage, available for retrieval at some time in the future (contrasts with short-term memory).
Long-term potentiation (LTP) - A lasting change in synaptic resistance following the application of electrical stimulation to living brain tissue. Possibly one of the biological mechanisms underlying the learning process.
Masking - The disruptive effect of an auditory or visual pattern that is presented immediately after an auditory or visual stimulus. This is backward masking, but there are other types of masking.
Means–ends analysis - A general heuristic where a sub-problem is selected that will reduce the difference between the current state and the goal state.
Mental model - A representation that we construct according to what is described in the premises of a reasoning problem, which will depend on how we interpret these premises.
Mental set - A term to describe the rote application of one successful method to solve a problem which makes one ‘blind’ to an alternative and possibly much simpler method.
Meta-analysis - A form of statistical analysis based on combining all the findings in a specific area to obtain an overall picture.
Misinformation effect - The contamination of eyewitness testimony by information acquired after the witnessed event.
Mnemonic - A technique or strategy used for improving the memorability of items, for example by adding meaningful associations.
Modality - The processing system specific to one of the senses, such as vision, hearing or touch.
Modular system - A system in which different types of processing are carried out by separate and relatively independent sub-systems.
Mood-congruent memory - The finding that learning and retrieval are better when the learner’s (or rememberer’s) mood state is the same as (or congruent with) the affective value of the to-be-remembered material.
Mood-state-dependent memory - The finding that memory performance is better when the individual’s mood state is the same at learning and retrieval than when it differs.
Morphemes - Units of meaning within words. A word like ‘descendant’ contains a number of morphemes which contribute to its meaning (‘de-’ = from, ‘-scend-’ = climb, ‘-ant’ = person with the property of).
Neologisms - Non-words which can be used by some neuropsychological patients in place of real words. The patients frequently do not know that they are not using real words. More widely, neologisms are used to refer to new words which are making their way into wider, more commonplace language use.
Neurotransmitter - A chemical substance which is secreted across the synapse between two neurons, enabling one neuron to stimulate another.
Numena - The world as it really is. (See also phenomena.)
Optimistic bias - An individual’s mistaken belief that he/she is more likely than most other people to experience positive events but less likely to experience negative events.
Organic amnesia - An impairment of memory function caused by physical damage to the brain.
Orienting - In the spotlight model of visual attention, this is attention to regions of space that does not depend upon eye movements.
Orienting task - A set of instructions used to influence the type of cognitive processing employed.
Overt attentional orienting - Making an eye movement to attend to a location.
Pandemonium - A fanciful but appealing conceptual model of a feature extraction process.
Parallel distributed processing (PDP -) approaches Stimuli are represented in the brain, not by single neurons, but by networks of neurons. An approach sometimes used to model cognitive processes.
Perception - The subjective experience of sensory information after having been subjected to cognitive processing.
Perceptual hypotheses - An element of the constructivist approach, in which hypotheses as to the nature of a stimulus object are tested against incoming sensory information.
Perseveration - An inability to shift response strategy characteristic of frontal lobe patients.
Phantom word illusion - What we hear may be influenced by what we expect to hear.
Phenomena - Numena as we perceive them.
Phenomenological experience - Our conscious experience of the world.
Phoneme - The smallest unit of speech which contributes to its linguistic meaning: changing a phoneme will change the meaning of a word.
Phonological loop - A hypothetical component of working memory, which is assumed to provide brief storage for verbally presented items.
Phonotactics - Rules which govern how phonemes can be combined and sequenced in any one language – for example, a syllable can start with ‘dw-’ in English, but a syllable cannot end ‘-dw’.
Pop-out - An object will pop out from a display if it is detected in parallel and is different from all other items in the display.
Positron emission tomography (PET) - A method of imaging structure and function in the human brain by directly tracking blood flow using radioactive tracers. PET can be used to form structural images of blood flow in the brain, as the brain is richly supplied with blood. PET can also be used to look at neural activity by tracking local changes in regional cerebral blood flow, which are seen when there is local increased in neural activity. Because the power of PET is limited by the number of scans, and because the number of scans is limited by the amount of radioactivity which can safely be administered, PET is becoming less commonly used for functional imaging studies.
Pragmatic reasoning schemata - Clusters of rules that are highly generalised and abstracted but defined with respect to different types of relationships and goals.
Primal sketch - First stage in Marr’s model of vision, which results in computation of edges and other details from retinal images.
Problem reduction - An approach to problem solving that converts the problem into a number of sub-problems, each of which can be solved separately.
Problem space - A term introduced by Newell and Simon to describe the first stage in problem-solving; represented in the problem space are the initial state, the goal state, the instructions, the constraints on the problem and all relevant information retrieved from long-term memory.
Procedural knowledge - Unconscious knowledge about how to do something. It includes skills and knowledge that cannot be made explicit but can be demonstrated by performance.
Procedural memory - Memory which can be demonstrated by performing some skilled procedure such as a motor task, but which the subject is not necessarily able to report consciously (contrasts with declarative memory).
Production system - A computational model based on numerous IF–THEN condition–action rules. IF the rule is represented in working memory THEN the production stored in long-term memory is applied.
Proprioception - Knowledge of the position of the body and its parts (arms, fingers, etc.). (See also haptic perception.)
Prosopagnosia - An inability to recognise faces despite adequate visual acuity.
Prototypes - Representations of objects in terms of fairly abstract properties. More flexible than templates.
Psychogenic amnesia - A memory impairment of psychological origin.
Psychological refractory period - The time delay between the responses to two overlapping signals that reflects the time required for the first response to be organised before the response to the second signal can be organised.
Recency and primacy effects - The tendency for participants to show particularly good recall for items presented towards the end (recency) or the start (primacy) of a list.
Recollection - Remembering a specific event or occasion on which an item was previously encountered.
Reconsolidation - The finding that the reactivation of a memory makes it temporarily vulnerable to change.
Recovered memories - Childhood traumatic or threatening memories that are remembered many years after the relevant events or experiences.
Re-entrant processing - Information flow between brain regions (bidirectional).
Regular orthography - Refers to a writing system in which there is a direct correspondence between speech sounds and letters. In irregular orthographies, like English, the relationship between speech sounds and letters is more opaque and variable.
Rehabilitation - Strategies used to help patients to cope with an impairment or disability, enabling them to function as effectively as possible within the limitations created by the impairment.
Representativeness heuristic - Making judgements on the basis of the extent to which the salient features of an object or person are representative of the features thought to be characteristic of some category.
Repression - Motivated forgetting of traumatic or other very threatening events (e.g. childhood abuse).
Retrieval-induced forgetting (RIF) - The phenomenon whereby the successful retrieval of a memory trace inhibits the retrieval of rival memory traces.
Retrograde amnesia (RA) - Impaired memory for events which occurred prior to the onset of amnesia (contrasts with anterograde amnesia).
Reversible figure - A figure in which the object perceived depends on what is designated as ‘figure’ and what is designated as ‘(back)ground’.
Saccade - The movement of the eyes during which information uptake is suppressed. Between saccades the eye makes fixations during which there is information uptake at the fixated area.
Saccadic eye movements - Small eye movements which are automatic and involuntary.
Schema - A mental pattern, usually derived from past experience, which is used to assist with the interpretation of subsequent cognitions, for example by identifying familiar shapes and sounds in a new perceptual input.
Scotoma - A blind area within the visual field, resulting from damage to the visual system (plural = scotomata).
Selection for action - The type of attention necessary for planning controlling and executing responses, or actions.
Selection for perception - The type of attention necessary for encoding and interpreting sensory data.
Selective filtering - An attentional task that requires selection of one source of information for further processing and report in a difficult task such as dichotic listening or visual search for a conjunction of properties.
Selective set - An attentional task requiring detection of a target from a small set of possibilities.
Semantic memory - Memory for general knowledge, such as the meanings associated with particular words and shapes, without reference to any specific contextual episode (contrasts with episodic memory).
Semantics - The meanings of words and the ways that this knowledge is structured and interpreted. Sentences can be ungrammatical but fully semantically comprehensible (e.g. I don’t want you to turn me down! I want you to turn me yes!).
Sensation - The ‘raw’ sensory input (as compared with perception).
Sensory conspicuity - The extent to which aspects of a stimulus (such as colour and luminance) influence how easily it can be registered by the senses. (See also attention conspicuity.)
Sensory overload - A situation in which there is too much incoming sensory information to be adequately processed.
Shadowing - Used in a dichotic listening task in which participants must repeat aloud the to-be-attended message and ignore the other message.
Short-term memory - Memory held in conscious awareness, and which is currently receiving attention (contrasts with long-term memory).
Sign language - A visual language, normally arising in deaf communities, in which the hands are used to express linguistic information. Sign languages are not just sequences of pantomimed gestures, nor are they typically visual forms of existing spoken languages – for example, British Sign Language has very little in common with spoken British English, having a very different syntax and rules for combining words. In sign language, the face is often used to replace the role of prosody and intonation in spoken language, being used to convey emphasis and emotion.
Size constancy - The perceived size of objects is adjusted to allow for perceived distance.
Slips of action - Errors in carrying out sequences of actions, e.g. where a step in the sequence is omitted, or an appropriate action is made, but to the wrong object.
Spectral cues - Auditory cues to, for example, distance provided by the distortion of the incoming stimulus by (e.g.) the pinnae (ear lobes).
Speech - Spoken form of a language: a way of conveying linguistic information with the human voice.
State–action tree - A diagram showing all the possible sequences of actions and intermediate states which can be constructed if the problem is well-defined.
Stroke - Refers to brain damage which occurs as a result of cardiovascular issues. The brain is an energy intensive organ, using around 20 per cent of the available oxygen circulating in the blood supply. Disruption to blood supply causes brain damage to occur very quickly. The damage can occur due to a blockage in a blood vessel (an ischaemic stroke) or due to a blood vessel rupturing (haemorragic stroke). Strokes are associated with sudden onsets of symptoms of brain damage, and the symptoms can reduce in severity as time passes.
Stroop effect - The effect of a well-learned response to a stimulus slowing the ability to make the less-well-learned response; for example, naming the ink colour of a colour word.
Subliminal - Below the threshold for conscious awareness or confident report.
Supervisory attentional system - A term used by Norman and Shallice to describe a system that can heighten a schema’s level of activation, allowing it to be in a better position to compete with other schemas for dominance and thus increasing its probability of being selected in contention scheduling.
Synaesthesia - A condition in which individuals presented with sensory input of one modality consistently and automatically experience a sensory event in a different modality (for example seeing colour on hearing musical notes).
Synaesthete - A person who has the condition synaesthesia.
Synapse - The gap between the axon of one neuron and the dendrite of another neuron.
Syntax - Grammatical rules of a language. These rules govern the ways that words can be combined (and declined). Syntax can be independent of meaning: a sentence can be syntactically correct but meaningless (e.g. ‘colourless green dreams sleep furiously’).
Templates - Stored representations of objects enabling object recognition.
Testing effect - The finding that actively testing a memory improves its subsequent retrievability.
Three-dimensional (3-D) - sketch Third stage in Marr’s model of vision. This is a viewer-independent representation of the object which has achieved perceptual constancy or classification.
Top-down (or schema-driven) processing - Processing which makes use of stored knowledge and schemas to interpret an incoming stimulus (contrasts with bottom-up processing).
Transcranial magnetic stimulation (TMS) - This technique uses an electrical coil placed near the surface of the head to induce a rapid change in the magnetic field, which, in turn, produces a weak electrical current in underlying brain tissue. This can cause depolarisation or hyperpolarisation. The technique can use single bursts or repetitive stimulation. It can be used to support inferences about the role of that brain region in a particular task (e.g. by showing that repetitive stimulation slows responses in task a but not task b, that the region is involved in task a).
Two-and-a-half-dimensional (2.5-D) sketch - Second stage in Marr’s theory of vision. Aligns details in primal sketch into a viewer-centred representation of the object.
Unilateral spatial neglect - A difficulty in noticing or acting on information from one side of space typically caused by a brain lesion to the opposite hemisphere (e.g. right-hemisphere damage producing lack of awareness for information on the left). Also called hemispatial neglect or hemispatial inattention.
Urbach–Wiethe disease - A disease in which the amygdala and adjacent areas are destroyed; it leads to the impairment of emotional processing and memory for emotional material.
Varied mapping - The condition in which a stimulus and its response are changed from trial to trial.
Ventral stream - A pathway in the brain that deals with the visual information for what objects are.
Visual masking - Experimental procedure of following a briefly presented stimulus by random visual noise or fragments of other stimuli. Interferes with or interrupts visual processing.
Visual search - Experimental procedure of searching through a field of objects (`distractors’) for a desired object (`target’).
Visuo-spatial sketchpad - A hypothetical component of working memory, which is assumed to provide brief storage for visually presented items.
Weapon focus - The finding that eyewitnesses pay so much attention to some crucial aspect of the situation (e.g. a weapon) that they ignore other details.
Wernicke’s area - A region of the brain normally located in the left temporal region, which is concerned with the perception and comprehension of speech.
Word - A word is a lexical unit which can stand alone in terms of its use in a language and its meaning. Words have meanings which map onto things and ideas: words are the level at which languages convey meaning.
Word-length effect - The finding that word span in immediate recall is greater for short words than for long words.
Working memory (WM) - A hypothetical short-term memory system which serves as a mental workspace in which a variety of processing operations are carried out on both new input and retrieved memories.
Writing - A visual system for representing a language. Writing systems can be alphabetic (where one symbol corresponds roughly to one speech sound), syllabic (where one symbol corresponds to one syllable), or ideographic/logographic (where individual symbols correspond to one word).