Language and cognition Flashcards
What is cognition?
Cognition;
The acquisition, retention and use of information that allows successful behaviour in our complex and changing environment
Encompasses concepts such as:
- Perception (not the same as sensation)
- Attention
- Memory and learning
- Emotion and social cognition
- Symbolic representations (language etc.)
- Reasoning and problem solving
How does cognition work within a sensory modality (hearing, vision or touch etc?)
Primary areas receive unprocessed modality data, association areas (also called higher-order areas) along with sub-cortical components function to determine the perceptual qualities of the modality
Modal qualities (e.g pitch, volume, timbre, harmonics for audition) from the higher-order cortex are integrated with both themselves and information from other sensory modalities (e.g sound & vision) (Majority given to the primary cortex and association makes sense of it?)
This integration allows the appreciation of music, detection of danger, integration of other peoples behaviour
Recall the secondary visual processing cortex for recognition of objects, faces and spaces
What is multi-sensory integration ?
Multi-sensory integration;
Combination of processed sensory perceptions (vision,
temperature, sound) are used to determine what is
happening, and where it’s happening
If it looks like fire, sounds like fire and burns you, it
probably is fire.
How do we go about interpreting these signals?
These three sensory modalities arrive in the cortex mantel at 3
primary locations
Sub-cortical structures & association fibres move the
information through the association cortices for processing and
integration to become either a reflex or a cognitive state
How does multi-sensory integration work for motor output?
1). Sensory information about the environments and body project to the prmary cortical areas (visual, somatosensory, auditory)
2). Information is then passed to the sensory association areas in the parietal lobe and the temporal lob for integration
3). From there integrated information is shared with the supplementary motor cortex (which is processing information about intent in association with other frontal lobe areas) & thence to pre-motor cortex to allow incorporation for sensory input into planned integrated motor events
What is the McGurk effect?
Visual sensory information I
Dominant sensation can change perception of sounds
Was saying bahh and changes lips but same sound to say far
What sensory and non-sensory information integrate?
Vision - Imagine you are alone in a dark forest late at night with dark shadows and strangely shaped trees
Auditory - Imagine the sharp crack of a twig breaking in the undergrowth near where you are standing
Emotion/memory- Remember that on the news and escaped homicidal inmate has been reported as escaping from prison less than half a mile from where you are
OR
Emotion/memory - Remember that you are there for a clandestine meeting with your partner for a romantic evening of Owl watching
Different outcome based upon association of sen sort and non-sensory information !
What Synaesthesia ?
Synaesthesia
The conflation of sensory experiences from one sensory domain with those from another, or the mixing of two modalities of the same sensory domain
Most commonly studied is called colour-graphemic synaesthesia where specific black and white shapes are perceived in colour
Associates things with colours and sees those colours when seeing known shapes etc
What area is used for speaking words ?
Broca’s area and primary motor cortex
(Left hemisphere is dominant for language)
What area is used for hearing words ?
Auditory cortex and Wernicke’s Area
(Left hemisphere is dominant for language)
What Wernicke’s area ?
The Wernicke — Geschwind Model:
- Visual information is passed to Wernicke’s
area via the angular gyrus, and so on to
Broca’s area etc. - The visual cortex can pass information
directly to Broca’s area but the path
remains elusive - A form of aphasia (conduction) occurs
when the link between the two areas (the
arcuate faciculus) is damaged, and is
typified by a reduced ability to repeat
What happens when you hear, understand and repeat spoken words?
1). Afferent information arrives at the auditory cortex and Wernicke’s area
(left temporal lobe)
2). Wernicke’s area comprehends the
words and passes the information to
Broca’s area for sentence
construction and syntax.
3). Broca’s area stimulates the motor
cortex to control the lips & tongue etc
The spoken word is repeated.
Note that other
association areas are
also lit up and so the
process is not clear
cut
What is Wernicke’s Aphasia ?
Aphasia- “the partial or complete loss of language ablates following brain damage”
Wernicke’s Aphasia;
Speech flows but is often nonsensical because the patient has reduced comprehension of
speech (their own and sometimes others) consequently sentence is very poor
Associated with a
“hearing/understanding words”
malfunction , sufferers do not understand
their own speech, and seem unconcerned that they do not make
sense.
However, this is complicated
by an inability of Wernicke’s
aphasics to also understand
written information,
The visual understanding
parts of the temporal lobe, specifically the ‘what’ pathway can also be affected
which helps explain this deficit.
What is Broca’s Aphasia?
Broca’s aphasia is also known as motor or non-fluent aphasia patients have difficulty speaking - often stuttering to find the right word. Patients are aware that they are making little sense. They have largely no problem responding to spoken or written word
What aree Broca and Wernicke’s areas linked by?
Arcuate fasciculus
Compare Broca and Wernicke’s aphasias?
Broca’s Aphasia;
- Stumbling speech with breaks and halts
- Poor grammar
- Poor syntax
- Word structure jumbled
- Repetition
- Comprehension maintained
Wernicke’s aphasia;
- Speech fluent but nonsensical
- Adequate grammar
- Adequate syntax
- Wrong or invented words
- No repetition
- Comprehension lost
Note that the right side of the brain is able to contribute to emotional content of language, spoken dysfunction of areas approximating to Broca’s and Wernicke’s results in aprosodia’s, which causes robotic or monotonic speech patterns (Aprosodia is a deficit in comprehending or expressing variations in tone of voice used to express both linguistic and emotional information)
Congenitally deaf patients with damage approximating to left brain language centres show signing deficits and comprehension deficits.
Those with damage to the right brain areas lack emotional colouring in their signing
What is seen in split brain patients?
Split brain patients cannot verbally identify objects felt behind the screen with the left hand as it is controlled by the right brain (no language), however objects in the right hand can be identified verbally
Split brain patients cannot verbally identify objects seen with only the left visual fields as it cannot communicate with the right brain (no language), however objects seen in the right visual field can be identified verbally
In both cases however, the right brain can communicate what it knows independently by drawing (visual task) or holding up fingers (if the hidden tasks was counting)
