8.1 Cortical function Flashcards
Where are most inputs to the cortex from?
Thalamus and other cortical areas
Where are most outputs from the cortex to?
Pyramidal cells
What are some characteristics of pyramidal cells?
Have dense dendritic trees with many synapses
What happens between the input and output
Information is processed in the complex synaptic network between input and outputs
What are the frontal lobe functions?
Motor Expression of speech Behavioural regulation/judgement Cognition Eye movements Continence
What is the main function of the frontal lobe?
Motor
Where is the expression of speech mainly found?
Left hemisphere
What can happen in a lesion of frontal lobe?
Can lose impulse control
What is an everyday example of frontal lobe syndrome, and what other lobe does it affect?
Drunk- disinhibition
Cerebellum- balance and movement
What are the functions of the parietal lobe?
Sensory Comprehension of speech Body image Awareness of external environment Calculation and writing Visual pathways projecting through the white matter
What is the main function go the parietal lobe?
Sensory
Where is the control of comprehension of speech usually found?
Left hemisphere
Where is the control of body image usually found?
Right
What is the name of one of the pathologies of parietal lobe damage?
Neglect
What is neglect?
When one is able to see the left side but unable to acknowledge it
Which visual pathway projects through the parietal lobe?
Superior optic radiation
What are the functions of the temporal lobes?
Hearing Olfaction Memory Emotion Visual pathways projecting through white matter
Which part of the temporal lobe is associated with hearing
Primary auditory cortex at superior temporal lobe
Which part of the temporal lobe is associated with olfaction?
Primary olfactory cortex at medial temporal lobe
Which functions of the temporal lobe are closely related?
Olfaction, memory and emotion
What else does the temporal lobe contain in terms of spatial recognition?
Contains map of the world according to us, including boundary cells to stop us from walking into walls etc
What is a symptom of temporal lobe epilepsy?
De Ja Vu
Which visual pathway runs through the temporal lobe?
Inferiori optic radiation
What is the concept of cerebral ‘dominance’? What can it be known as instead?
The different hemispheres have different main functions
Could be known as cerebral lateralisation
What is the left hemisphere focused on?
Language
Mathematics/logic
What is the right hemisphere focused on?
Body image
Visuospatial awareness
Emotion
Music
Why can the left spatial side be more affected with relation to cerebral dominance?
Left hemisphere deals with right sequential processing
Right side deals with left and right side
So loss of one of the hemispheres, the right is being processed by both sides
What is the blood supply to the corpus callosum?
Anterior cerebral artery
What is the result of damage to the corpus callosum?
Alien hand syndrome
Right hemisphere doesn’t know what left hemisphere is doing
Vice versa
Where are the language pathways found primarily?
In dominant left hemisphere
Name two of the language centres of the left hemisphere
Broca’s area
Wernicke’s area
What connects the two language centres?
Arcuate fasciculus
Where is Broca’s area found? What does it sit close to?
Inferior lateral frontal lobe, sitting v close to pre central gyrus (movement)
What is the function go Broca’s area?
Production of speech
Where is Wernicke’s area found? What does it sit close to?
Superior temporal lobe, sitting close to the primary auditory cortex
What is the function of Wernicke’s area?
Interpretation of language
Describe the pathway for repeating a heard word. And what happens at Wernicke’s and Broca’s area?
Heard word –> Primary auditory cortex –> Wernicke’s area converts vibrations from cochlea to language–> arcuate fasciculus–>Broca’s are–> Precentral gyrus that makes larynx, pharynx and tongue move
Describe the pathway for repeating a written word. And what happens at Wernicke’s and Broca’s area?
Reading = visual cortex (occipital)–> Wernickes area that converts patterns of lines to language –> arcuate fasciculus–>Broca’s area–> Precentral gyrus that moves the mouth
Describe the pathway for speaking a thought.
Input from all over the cortex–> Wernickes–? arcuate fasciculus–> Broca’s–> Precentral
What are the symptoms of Wernicke’s aphasia?
Fluent gibberish
Not able to comprehend
Cheerful
What are the symptoms of Broca’s aphasia?
Trouble speaking
Unable to make words easily
Able to comprehend what is being said
Distressing as they are unable to speak
What are the types of memory?
Declaritive/Explicit
Non-declaritive/Implicit
What is included in declarative/explicit memory?
Facts
What is included in non-declarative/implicit memory?
Motor skills and emotions
Where are memories stored?
All over the brain, in a global pattern
Where are explicit memories stored?
Cerebral hemispheres
Where are implicit memories stored?
Cerebellum and basal ganglia
Describe learning to do a habit e.g. cycling in terms of brain parts involved
Using primary motor cortex and sensory cortex when learning and once learnt transferred to cerebellum doe thoughtless action
What are the 2 types of memory stores?
Short term and long term
How is short term memory converted to long term memory?
Consolidation
What does consolidation depend on?
Emotional content
Rehearsal
Association
Which part of the brain is crucial for consolidation? Which memories in particular?
Hippocampus Particularly declarative (explicit)
What does the hippocampus do with all the inputs, and where do these inputs come from?
From all over the brain: visual. auditory, somatosensory, limbic etc
Takes these inputs and makes associations
What is neuroplasticity and what does it involve?
The molecular and cellular mechanism of memory
Involves the strengthening go synaptic connections
