5b: Brain and behaviour (language) Flashcards
Define phenome and morphemes
Phoneme: the smallest unit of speech sound in a language that can signal a difference in meaning
Morphemes: the smallest units of meaning in a language (usually 1 syllable, combined into words)
What is syntax
Rules and principles which govern the way in which morphemes and words can be combined to communicate meaning in a particular language
Brief stages of language
1-3 moths 4-6 months 7-11 months 12 months 12-18 months 18-24 months 2-4 years 4-5 years
1-3- can distinguish speech from non speech. Cooing and crying
4-6m- babbling sounds from every language.
7-11m- babbling includes only phenomes heard in langayge the baby is exposed to. Imtates
12m - first recognisable word spoken
12-18m- single words to express whole phrases or request
18-24m - vocab expands to 50-100 words
2-4y-vocab expands at sever hundred words every 6 month s
4-5y- basic grammatic rules achieved
Influences on language development?
Environment: Genie, deprived of social interaction, age 13, lacks linguistic competence after 7 years of rehab
Genes: Gene expression realises basic neural mechanisms for language
Conditions –e.g. autism, ADHD, developmental verbal dyspraxia, hearing impairment
Why is there a critical period in language acquisition
Language can be acquied well until age 4, then galls to age 8 and is virtually mpossible after age 10.
Due to pruning of neurons
Strucutres underling language
95% of right handed people, have LEFT-DOMINANCE FOR LANGUAGE
- 8% of left handed people have RIGHT-HEMISHERE DOINANCE
- 8% of left handed have BILATERAL
Receptive aphasia affects which brain area
Wernicke’s area
Expressive aphasia affecs which brain area
Broca’s area
Characteristics of broca’s aphasia
Non-fluent speech
Impaired repetition
Poor ability to produce syntactically correct sentences
Intact comprehension
Characteristics of wenick’s aphasia
Receptive;
problems in compreension
Fluent, meaningless speech
Paraphasias (semantic and phonemic)
Neologisms
Poor repetition
Impairment in writing
Outline the language pathway
Primary auditory cortex
Wernicke’s area (analyses sound to determine what was said)
then, via the arcuate fasciulus, to:
Broca’s area (forms motor plan)
Motor cortex (implements plan by manipulating larynx and related structures)
Consequence of lesions to arcuate fasciuculus
Disrupts connection between broca’s and wecnicke’s
Trouble repeating information
However can retain comprehension of spoken language (as wernicke’s is fine)
and can speak sponatnously (intact broca’s area)
Conditions associated with aphasia
Lesions to the dominant hemisphere can be caused by:
- Stroke
- Traumatic brain injury
- Cerebral tumour
- Progressive neurodegenerative conditions
What is dysexecutive syndrome
disruption of executive function and is closely related to frontal lobe damage
What is executive function
mental processes that enable us to plan, focus attention, remember instructions, and juggle multiple tasks successfully.
Causes of dysexecutive syndrome
head trauma, tumours, degenerative diseases, and cerebrovascular disease, as well as in several psychiatric conditions
Behavioural aspects of dysexecutive syndrome
Hypoactivity
Lack of drive
Apathetic
Poor initiation of tasks
Emotional aspects of dysexecutive syndrome
Hyperactivity
Impulsive
Disinhibited
Socially inappropriate
Rude, crass, prone to swearing
Cognitive aspects of dysexecutive syndrome
Attentional and working memory difficulties
Poor planning & organisation
Difficulty coping with novel situations and unstructured tasks
Deficits associated with following areas of frontal lobe:
Orbito-frontal
Medial
Lateral
Impulsivity, disinhibition
Loss of spontaneity, initiation (akinetic mutism)
Inability to formulate and carry out plans
T/F only the frontal lobe is involved in executive function
F…. there are lots of areas including subcortical regins like:
Basal ganglia
Thalamus
Cerebellum
