memory, language and executive dysfunction Flashcards
what are the stages of memory *
registration - input from senses, and attention and ability into the memory system
encoding - processing and combining the recieved info
storage - holding of that input in the memory system, assimilate with already known info
retrival - recoving stored info from the memory system (if problem at this stage would benefit from prompts/cues)
what stage of memory does alzhiemer’s effect *
encoding
prompts dont help
theory 2 of memory - duration *
conceptual divisions in memory systems
- sensory - not last long, might not be aware of it at all
- working/short term mem - few seconds - when info processed it is laid down as this
- long term memory - few days
describe the model for memory incorporating stages and duration *
info goes into sensory receptors - some info lost, some laid down as short term memory if we focus attention on it; rehearsal means it will stay in short term, if not rehearsed there is a limited capacity so info is lost
info can be stored in long term mem - either from short term or from sensory
info from long term is retrieved (reactivating working mem) - dont know if this is by same architecture as laying down memory eg hippocampi
longterm memory is transferred to neocortex
what are the different types of memory *
long term memory is composed of declaritive and non-declaritive
declaritive composed of episodic (problem present that cant remember anything from on holidy for eg), or semantic (acquired knowledge eg capitals)
non-declaritive (w/o consciousness, usually well conserved in lesions) made of procedural (eg driving), priming, conditioning, non-associative learning
areas of the brain involved in different aspects of long term memory *
declaritive (explicit) - medial temporal lobe/diencephalon
procedural - striatum
priming - neocortex
simple classical conditioning
- emotional response - amygdala
- skeletal musculature - cerebellum
what part of the brain does episodic memory involve *
medial temporal lobe including hippocampus, enterhinal cortex, mammillary bodies, parahippocampal cortex
effect on memory of bilateral removal of the temporal lobe *
remove the hippocampus = memory deficits - responsible for learning of declaritive memory - cant remember what just happened
basal ganglia project to prefrontal so might be involved in the problem - retrival deficit
what type of memory is the temporal lobe related to *
semantic memory
what type of memory is associated with prefrontal cortex *
working memory
retrival
what type of memory is the cerebellum associated with *
procedural memory
summarise memory disorders *
total amnesia is rare - especially when there is otehrwised preserved cognition
many neuro conditions effect memory with different lesion sites
the various aspects of memory are effected in different ways by different disorders
eg episodic, semantic (primary semantic deficit - semantic dementia), anterograde/retrograde dementia - when people have siezures or epilepsy they might have remote memory problems
implicit memory or learning are often on tact - for example mirror drawing improves each time a person does it, even of they have no declaritive memory of having done it before
effect of temporal lobe damage by herpes encephalitis
procedural memory fine
but unable to lay down new memories
describe modality of memory *
L hemisphere mainly concerned with verbal information processing
R with non-verbal - ie face processing so prosopregnosia is likely to effect R
describe the serial position effect
have primicy effect and recency effect
more likely to remember words at start and end of list
in alzheimer’s the primicy effect is lost - memory already gone because the coding is deficit
what alters the probability of remembering words
order
personal salience
number of words
chunking or other encoding strategy - repeat the lsit a few times to see if people can do this - in fronto/fronto-striatal disruption difficulty chunking even with repetition
delay time
distraction
clinical implication of the way we remember
give important info at the beginning and end
emphasise and repeat important info at end
make salient - ie link back to initial concerns
chunk info into meaningful categories
avoid overloading with information - working memory is 7+/- 2 items
can use pneumonics
summarise language
it is ubiquitous
a system of symbols, rules and structure that enable us to communicate
nio humans found without language
debate whether innate (because universal across cultures) or exposure
both organic and environmental factors are important - there is a critical time frame for language develop, we are designed to develop language but this depends on exposure
what is the structure of language
phenome - the smallest uniot of sound in a language that can signal a difference in meaning - humans can express just >100, in english there are 44
morphemes are the smallest units of meaning in a language - typically 1 syllable, combined to make words
words
phrases
sentences
written text and conversational discourse
what is syntax
rules that govern teh way morphemes and words are combined to communicate a particular language
theory of universal grammer - under normal conditions humans will develop language with particular properties eg distinguishing nouns from verbs
children of parents who speak pidgin language ie with no grammer, develop languages which are fully gramatical - suggests that there needs to be some exposure but an innnate part of the brain controls syntax
describe language development *
1-3months - distinguish speech and nonspeech, prefer speech, undifferentiated crying gives way ot cooing when happy
4-6months - babbling sounds - contain sounds from every language, child vocalises in response to vocalisation from others
7-11months - only phenomes heard in own language, child moves tongue with vocalisations, child discriminates some words without understanding their meaning and begins to initiate word sounds herd from others
12months - firts recognisable words as 1 word utterence
12-18 - increase knowledge of meaning, use single words to express whole phrases, usually nouns
18-24 - vocab extends to 50-100 words, 1st rudumentory sentances usually 2 words, little use of articles, conjunctions, or axillary verbs
2-4yrs - vocab expands rapidly, get larger sentences, grammatically incorrect but express basic syntax, expresses concepts with words and describe imaginary objects and ideas
4-5yrs - child has learnt basic gramatical rules for combining nouns, adjectives, articles, conjugations and verbs into meaningful sentences
what happens if children are raised without exposure to language
they are w/o language
even with rehab still incompetent
describe the critical period for lanuage gain *
<5yrs
between 5 and puberty it is harder
we know this because of 2nd language acquisition, children with brain injuries at different stages and feral children raised w/o language
exposure to language is required
describe hemispheric specialisation for language *
95% of R handed people have L hemisphere dominance
19% of L handed have dominance for R, another 19% have no dominance
therefore post-brain injury dominance may effect recovery
effect of lesion to broca’s area *
non-fluent speech
impaired repitition
poor ability of syntax
intact comprehension
effortful expression
this is expressive aphasia
where is broca’s area *
l hemisphere, frontal region
describe wernick’s aphasia *
receptive aphasia
problem in comprehending speech - input/reception of language
fluent meaningless speech - wouldnt notice the aphasia if you didnt speak their language
paraphasias - errors in producing specific words
semantic paraphasias - substituting words similar in meaning
phonemic paraphasias - substituting words similar in sounds
neologisms - non-words
poor repitition
impairment in writing
can managage aspects of conversation - eg speak at right time but cant respond to specific qns
where is wernick’s area *
temporal lobe
describe the language circuits*
info about sound is analysed in cortex and sent to wernick’s area
wernick’s area analyses this to see what word was said
this info goes through the arcuate fasiculus to broca’s area
broca’s area forms a motor plan to repeat the word and sends it to motor cortex
motor cortex illicts plan
effect of lesion to arcuate fasciculus *
cant repeat word
but can understand because of intact wernick’s
and can speak spontaneously because of intact broca’s
what are the different types of aphasia *
global - not fluent, cant comprehend, cant repeat
mixed trasncortical - not fluent, cant comprehend
broca’s - not fluent, cant repeat
transcortical motor - not fluent
wernick’s - cant comprehend or repeat
transcortical sensory aphasia - cant comprehend
conduction- cant speak
anomic - naming deficit - common
what conditions are associated with aphasia *
lesions to dominant hemisphere caused by:
stroke
tBI
cerebral tumour
progressive neurodegenerative conditions - primary progressive aphasia
what is the new theory of localisation of language *
not just 1 key connective tract - there are many eg uncinate fasciculus, the inferior front-occipital fasciculus, the middle longitudinal fasciculus, inferior longitudinal fasciculus
language is distributed throughout brain - involving frontal, temporal, parietal in middle hemispheres, and the basal ganglia, thalamus and cerebellum
what is dysexecutive syndrome *
the disruption of executive function and is closely related to frontal lobe damage
has cognitive, emotional and behavioural symptoms
what is executive function *
the mental processes taht allow us to plan, focu attention, remember instructions and juggle multiple tasks
it coordinates response for different things - not just 1 function
involves inhibiting response
causes of dysexecutive syndrome (*
head trauma
tumour
degenerative disease
cerebrovascular disease
psychiatric problems
what are the 2 possible behavioural and emotional aspects of dysexecutive syndrome *
1
- hyperactivity
- impulsive
- disinhibited
- perseverative
- emotional dysregulation
- socially inappropriate
- rude, crass, prone to swearing
2
- hypoactivity
- lack of drive
- apathetic
- poor initiation of tasks
- lack of spontinuity
- emotional bluntness
- theory of mind difficulties - social cognitive difficulties - dont know whats in other people’s minds
- reduced empathy
get either of these - dependant on discrete brain areas
cognitive effects of the dysexecutive syndrome *
attentional and working memory difficulties - prefrontal cortex
poor planning and organisation
difficulty coping with novel situations and unstructured tasks
difficulty switching from task to task
difficulty keeping track of lots of tasks
difficulty with complex/abstract thinking
what regions of the frontal lobe are effected in dysexecutive syndrome *
prefrontal cortex - memory
orbito-frontal - impulsivity and disinhibition - behaviour change
medial - loss of spontaneity, initiation - lack of drive, apathy (not depression - report mood as fine), akinetic mutism
dorsolateral - inability to formulate and carry out plans - cognitive problems
describe the connections between prefrontal cortex and subcortical structures in dysexecutive syndrome *
it means that conditions look like there is a problem in the frontal cortex, but actually the damage is to subcortical areas
eg movement disorder - parkinsons can develop apathy because of connections, not necessarily direct damage to frontal regions
