Cerebral functional areas Flashcards
telencephalon grey matter
cerebral cortex (outer covering of grey matter - highly folded which increases SA - lots of synapses) \+ basal nuclei \+ limbic structures (hippocampus & amygdala)
telencephalon white matter
projection, commissural, association
The diencephalon
though housed between the hemispheres, is not part of the cerebrum (telencephalon)
Each cerebral hemisphere consists of 5 lobes
Frontal lobe is specialised in motor output (action),
Parietal, occipital & frontal lobes are specialised in sensory input (perception)
Insular cortex
Primary gustatory cortex
the insula is located deep inside the lateral sulcus & cannot be allocated to any of the lobes
Hierarchical organisation of the cerebral cortices
1. primary cortical areas
motor sensory: • somatosensory • visual • auditory • taste (gustation) • olfaction
Hierarchical organisation of the cerebral cortices
2. secondary association (specific) areas
adjacent to primary
• modality specific (unimodal)
• interpret
Hierarchical organisation of the cerebral cortices
3. tertiary (broad) association areas:
- multimodal
- more broad functions: cognitive abilities, emotions, personality
- some lateralisation of function
3 broad association areas
Posterior association area
Frontal association area - prefrontal cortex
Temporal association area
Frontal association area - prefrontal cortex
Focus attention
• Motor expression of emotions and behaviour
• Exploration of the environment
Temporal association area
Lateral & medial temporal lobe
• Associate perception with previous experience
• Link recognition with meaning
Posterior association area
Margin of the parietal, temporal & occipital lobes
• Interprets multimodal sensory information
• Awareness of self & extrapersonal space
Simplified hierarchical organisation of the sensory cortices flowchart
Sensory input (e.g. visual, auditory, tactile, movement) > thalamus > primary sensory cortices (unimodal cortex) > secondary association centre (unimodal cortex) > Highest order association cortices (multi(hetero)modal cortex)
sensory cortices
Cerebral cortices of OCCIPITAL, PARIETAL, AND TEMPORAL LOBES
Simplified hierarchical organisation of the sensory cortices
- 1˚ sensory cortex (PSC) receives sensory information from the thalamus
- PSC conveys information to the 2˚ association cortex for interpretation (e.g. 20 somatosensory area combines tactile, pressure & proprioceptive information to ‘recognise’ an object.
- multiple 2˚ associationcortices send their sensory information to the multimodal posterior association area for integration
Simplified hierarchical organisation of the motor cortices flowchart
Prefrontal cortex (highest order association cortex) > SMC - Supplementary Motor Cortex /PMC =PreMotor Cortex > Primary motor cortex (M1) > pyramidal pathway> SPINAL CORD > Somatomotor output
Simplified hierarchical organisation of the motor cortices
- Motor command is initiated in the brain and exits the brain via the primary motor cortex(M1)
- The prefrontal cortex / anterior association area generates motor commands and transfers them to secondary motor cortices (SMC & PMC) for purposes of integration of motor skills
- Secondary association cortices (SMC&PMC) transfer the motor command to the primary motor cortex (M1) for execution
motor cortices
Cerebral cortex of the FRONTAL LOBE
SMC = Supplementary motor cortex;
PMC = Premotor cortex
Frontal lobe
Primary motor cortex Secondary motor areas premotor area Supplementary motor area: Frontal eye field Broca’s area prefrontal cortex
Frontal lobe - Primary motor cortex:
precentral gyrus – outflow = corticospinal tract
Frontal lobe - Secondary motor areas
planning & initiation of movements, motor maps
Frontal lobe - premotor area
posterior middle frontal gyrus & opercular part inferior frontal gyrus
Frontal lobe - Supplementary motor area:
posterior portion superior frontal gyrus
Frontal lobe - Frontal eye field
= posterior end middle frontal gyrus just rostral to premotor
Frontal lobe - Broca’s area:
triangular & orpecular parts, inferior temporal gyrus in dominant hemisphere
= motor aspects of language symbols – spoken, written & sign
Frontal lobe - prefrontal cortex
executive functions, motor expression of emotions & behaviour
Mirror neuron system
Network of neurons throughout all cerebral cortices
• Motor learning
• Empathy
the anterior commissure
lies within lamina terminalis, which in turn forms the anterior wall of the 3rd ventricle.
The falx cerebri
separates the left & right frontal, parietal, occipital & cingulate portions of the limbic lobes.
