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Flashcards in Basic Definitions (All topics) Deck (30):

Define: Dyslexia

A general term meaning difficulty with reading (e.g., interpreting words, letters and; other symbols).

- Does not refer to specific types or symptoms of difficulty reading (e.g., is not 'letters jumping around the page")
- Can be acquired or developmental


Define: Acquired Dyslexia

Acquired dyslexia is impaired reading occurring as a consequence of brain injury in a previously literate person.


Define: Developmental Dyslexia

Developmental dyslexia refers to unexpected difficulty in learning to read in the first place. (a developmental failure in reading)


What is 'Aphasia'?

An acquired disorder of language production (i.e., after language has been fully acquired). May affect all modalities of speech together, or just separate ones.

NOTE that in Developmental spoken language deficits would be considered a specific language impairment (SLI) and should reflect failures to fully acquire the same component a the adult spoken language system.


What is a 'memory'?

Binding is the core concept, a memory is effectively the binding of contiguous neural representations of 'what' 'when' 'where' and 'how' (i.e., the combination of these features make up the 'memory'.

In other words: an event/episode is defined by the conjunction of spatial and temporal features associated with an act (e.g., done by you, observed by you, told to you)


Define delusions (3-factors definition, NOT DSM-V definition!)

A belief --> delusions when:

Incomprehensibility = sheer fantastical delusional content held despite contextual lack of evidence.
Incorrigibility = Resistance to counter evidence/argument
Unwarranted subjective conviction = The belief/delusions has the quality of being a 'self-evident' truth.


What is cognitive neuropsychiatry?

A field of cognitive psychology which seeks to learn more about the normal operation of high-level aspects of cognition such as belief formation, reasoning, decision making, theory of mind, and pragmatics by studying people in whom such processes are abnormal.


What is cognitive neuropsychology?

Scientific investigation of cognition (e.g., attention, perception, learning, memory, spoken and; written language, thinking and belief formation - where information/knowledge about these processes is obtained via study of individuals whose mental processes are not functioning normally (either due to acquired brain injury or due to a developmental abnormality)

This is in contrast to cognitive psychology which studies the same thing through healthy individuals.


What is a cognitive model?

Breaking a cognitive process into the modules and connections between modules.


What is an 'association'?

Deficits that occur together (e.g., a syndrome - cluster of deficits that often occur together).


What is a single dissociation?

Evidence of a deficit occurring in the absence of another deficit.

For example, difficulty perceiving faces but still being able to perceive objects. or difficulty reading non-words, but being able to read words.


What is a double dissociation?

One or more patients show poor performance on task A with good performance on task B; while one or more patients who poor performance on Task B with good performance on Task A.

A double dissociation rules out resource artifacts interpretations and provides strong evidence for divergent cognitive processes.


What is a 'case study'?

Case studies are intensive scientific study (read: multiple experiments) of a single individual with a cognitive deficit.


Define the following principle of cognitive neuropsychology: Modularity

This is the CORNERSTONE of cognitive neuropsychology.

Modularity describes the notion that cognitive models are comprised of 'modules' (i.e., cognitive processors) and the connections between them.

Modules have three main properties:
1. Informationally encapsulated = each module has a specific role/performs a specific function. It performs this process ignorant and isolated from other modules.
2. Domain Specific = Can only accept one type of input (e.g., visual of letters)
3. Mandatory = The system will always try to use this module in the normal way even if it is damaged! Modules are not under voluntary control.


Define the following principle of cognitive neuropsychology: Fractionation

Fractionation describes the notion that brain damage SELECTIVELY damages some modules and not others.

IN OTHER WORDS: brain damage leads to specific deficits as it damages specific modules (like damaging part of a computer, and NOT like a sponge with a bit missing).

also # in cognitive neuropsychology the LOCATION in the brain of modules may be interesting but not necessary knowledge, it doesn't really matter.


Define the following principle of cognitive neuropsychology: Subtractivity

Subtractivity describes the notion that brain damage/deficits subtract particular cognitive modules or pathways of communication between modules - but CANNOT add new modules or new pathways i.e., system stays the same.


Define the following principle of cognitive neuropsychology: Universality

Universality describes the idea that everyone's cognitive system is approximately the same. Same models used to do the same functions.

Note that 'everyone' is a relative term e.g., English versus Hebrew speakers likely have differences in letter ID module.


What is a RESOURCE ARTIFACT (in describing single dissociations)

RESOURCE ARTIFACTS = where one could conclude that two tasks require the same underlying processing mechanism, but one task demands more from these mechanism (i.e., is harder) than the other, and consequently shows greater impairment when the mechanisms are damaged.


Define: 'attention' (broadly)

Attention is the behavioural and cognitive process of selectively concentrating on a discrete aspect of information while ignoring other perceivable information.

(JAMES 1890: the taking possession by the mind, one out of what seem several simultaneously possible objects or trains of thought. Withdrawal from some things in order to deal effectively with others.

Focalization, concentration.


What is 'top-down attention?

Endogenous (voluntary), goal-directed attention.


What is 'bottom-up attention'?

Exogenous (involuntary).


What is contingent attentional capture?

Some evidence we are only captured by things that match our task-set (i.e., contingent capture) - (e.g., looking for a particular colour, may mean more likely to be captured by a new colour, but not another type of onset.) -- suggesting a dynamic interplay between top-down and bottom-up processes!

THINK ABOUT: the virtual reality driving study i.e., When the colour of direction signs a participant was asked to follow did NOT MATCH the colour of the motorbike - they were more likely to crash than when the colours did match.


What is inattentional blindness?

When you are concentrating/fixated on a goal (Top-down attention) to the extent that even an unusual event that would normally capture attention, fails to do so! (i.e., you are using all of your attentional capacity!)


What is attentional blink?

Attentional Blink (AB, or 'blink') is the phenomenon that the second of two targets cannot be detected or identified when it appears close in time to the first. The closer in time, the more likely it will be missed.


What is attentional capture?

When attention is fixated and attending in one place, when something outside that 'spotlight' grabs attention (bottom-up attention).


What is Neglect Syndrome?

Neglect is a disorder of attention that occurs after damage to one side of the brain (usually right-sided, parietal lobe often implicated). Clinically presenting as a failure to attend to one side of space (often the left, if r-hemi dmg).

May present as:
- acting as though affected side of space has ceased to exist (contralateral to lesion)
- can also be a bias towards the ipsilesional side (e.g., in orientating)
- ignore food on one side of their plate
fail to shave or make-up one side of their face
- bump into objects on one side
- fail to read text from one side of the page


What is apperceptive agnosia?

What type of neuroanatomical damage is linked with this kind of agnosia?

Impaired shape identification, impaired copying/matching/tracing, difficulty judging line orientation (horizontal vs/ vertical) - affects ALL kinds of visual stimuli (words/objects/faces)

- can reach for objects accurately and negotiate a path
- acuity, brightness discrimination, and colour vision (visual senses) are all ok!

Apperceptive agnosia the deficit occurs earlier is processing (occipital [sometimes parietal] vision areas) and patients have difficulty forming visual representations of visual images/shapes/objects (and therefore have difficulty recognising and copying images). Theories to be due to a deficit in perceptual group processes such as that outlined by the gestalt psychologist (e.g., proximity, similarity, closure, good continuation etc).

Typically occurs after gross bilateral damage to occipital (sometimes parietal lobes), particularly where damage is diffuse (Rather than focal) e.g., carbon monoxide poisoning.


What is associative agnosia?

What type of neuroanatomical damage is linked with this kind of agnosia?

- Impaired recognition of complex forms and objects (what is this a picture of!), early visual processing is much more intact (can copy and match! and some can draw from memory). Can access semantics - BUT NOT VIA VISUAL IMAGERY!

Classically considered perception stripped of meaning , however, some stored knowledge can be intact (some can draw from memory) and context can be helpful (i.e., better with real objects in scenes than isolated drawings).

Lesions typically bilateral ventral (occipital-temporal pathway)


What is prosopagnosia?

What type of neuroanatomical damage is it associated with?

- an VISUAL impairment in recognising familiar faces (#person recognition can occur non-visually e.g., voice and memory is intact)

Bilateral mid-fusiform lesions


What is Theory of Mind?

Theory of mind (often abbreviated ToM) is the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge, etc.—to oneself and others and to understand that others have beliefs, desires, intentions, and perspectives that are different from one's own.