Language Flashcards
What is language?
A system for representing, communicating information about the world using symbols and rules
What are the different types of language?
Natural language vs. ‘formal’ languages
Formal languages
= finite systems of signs and rules for combination
Human language vs. animal languages - Bees, primates, cetaceans - Closed / finite vs. generative - Capable of representing abstract concepts
Where do languages come from?
Modern languages evolved from ancestral languages
What are the functional components of language?
- Articulation (Phonetics)
- Phonology
- Meaning (Semantics)
- Syntax
- Comprehension
What is articulation?
Movement of the tongue, lips and jaw to modify a sound wave
How is articulation classified?
Classified by place of articulation
- Labial
- Alveolar
- Palatal
And by manner of articulation
- Voiced vs. unvoiced
- Fricative, plosive etc.
What is phonology?
The sound combinations from which the syllables and words of a language are built up
‘Legal’ phonological structure varies across languages
The International phonetic alphabet (IPA) is used as a common notation
What is semantics?
The representation in long term memory of concepts and the relations between them
Actions, objects, properties → verbs, nouns and adjectives
Largely independent of grammar
Mapping between concepts and symbols generally arbitrary
though nb onomatopoeia – e.g. ‘hiss’
What is syntax?
The arrangement of words and phrases to create well-formed sentences in a language
What does syntax rely upon?
Relies on grammatical markers and word order
In English, word order (SVO) is paramount in assigning role:
What is comprehension?
The ability to represent the meaning of words or sentences spoken or written by another person
What factors contribute to comprehension?
context
pitch
stress
prosody
Describe the structures of the language network
Dependent on a left hemisphere of cortical regions and white matter connections
Left inferior gyrus (broca’s area)
Inferior frontal lobe
Auditory cortex critical for understanding speech
Anterior regions of temporal lobe needed for representing meaning
Wernicke’s area important for decoding an incoming speech signal
White matter tract - arcuate fasciculus connects anterior and posterior parts of the language network together
Which part of the brain language network is responsible for articulation and phonology?
Dependent on the inferior and apercular parts of the motor homunculus of cortex; (anterior portions of broca’s area) - control movements of tongue, mouth, larynx and glottis
Which brain region mediates meaning and semantics?
L+R Temporal poles due to dense interconnections between them with widespread regions of association cortex
‘Modality-independent’ representations
Where is syntax regulated?
Arrangement of words into meaningful sentences is mediated via the left inferior frontal gyrus, extending into the insula
Which part of the language network is responsible for comprehension?
Primary auditory cortex to hear Temporal poles allows understanding of symbols Left inferior frontal gyrus for syntax Arcuate fasciculus Left posterior superior Temporal gyrus
What can cause language change?
Brain damage due to
- stroke (ischaemic/haemorrhagic)
- Neurodegeneration
What disorders are caused by stroke?
Broca’s aphasia
Wernicke’s aphasia
Conduction aphasia
Adynamic aphasia
What is broca’s aphasia?
Difficulty with articulation and phonology
Speech: Halting, fragmented, distorted, agrammatic
Comprehension: Preserved for words; reduced for sentences
Follows damage to: Broca’s area
Typical pathologies: Middle cerebral artery infarction; haemorrhagic stroke
Describe Wernicke’s Aphasia
AKA ‘Receptive aphasia’ or ‘sensory aphasia’
Speech: Fluent, often with meaningless phonological strings
Follows damage to: posterior regions of language network
Typical pathologies: penetrating brain injury; cerebral haemorrhage
What is conduction aphasia?
Difficulty with repetition
Speech characteristics: Mild fluency and comprehension difficulties
Test: single word and sentence repetition
Follows damage to
posterior perisylvian regions and underlying white matter
Typical pathologies
lacunar stroke
Outline dynamic aphasia
Difficulty planning, initiating or maintaining speech
Speech characteristics: Reduced, fragmentary, echoic, preservative speech
Test: High vs. low constraint sentence completion
Follows damage to
Anterior left inferior frontal gyrus (BA 45)
Typical pathologies
Left anterior cerebral artery infarction
What are the different types of neurodegeneration
- Nonfluent progressive aphasia
- Fluent progressive aphasia
- Logopenic progressive aphasia
