Cerebral Hemispheres Flashcards
What are the dips and elevations of the cerebral hemispheres called?
Sulci - dips
Gyri - elevations
What is the basal ganglia?
Collection of neuronal cell bodies buried in the white matter
What are the cavities in each hemisphere called?
Lateral ventricle
What is the fissure that separates the two hemispheres?
Medial longitudinal fissure
What is the corpus callosum?
Axons going from one cerebral hemisphere to the other
What sulcus goes all the way from the lateral sulcus to the medial surface and divides the cerebral hemispheres into lobes?
Central sulcus
What part of the cerebral hemisphere is motor?
Anterior
What part of the cerebral hemisphere is sensory?
Posterior
What is the function of medial portions of the hemispheres? What is the name for these areas?
Limbic system - storage and retrieval of processed information
What is area 4?
Frontal lobe - pre central gyrus
This is primary motor cortex
What are areas 44 and 45?
Inferior frontal gyrus - Broca’s area of motor speech
What is the prefrontal cortex?
Cognitive functions of higher order
Intellect, judgement, prediction and planning
What is the parietal lobe?
Somatosensory
What is the post-central gyrus?
Areas 3, 1, 2 - primary sensory area
Receives general sensations
What is the superior parietal lobule?
Interpretation of general sensory information and conscious awareness of contralateral half of body
What is the inferior parietal lobule?
Global association area
Interface between somatosensory cortex and visual and auditory association areas
Contributes to language functions in dominant hemisphere
What is the temporal lobe responsible for?
Hearing, smell
What is the superior temporal gyrus?
Primary auditory cortex
Areas 41, 42
What is the location of the auditory association areas and what is their function?
Posterior to 41, 42
Wernicke’s area in dominant hemisphere, crucial for understanding spoken word
Has connections with other language areas
What is the function of the inferior surface of the temporal lobe?
Receives fibres from olfactory tract
Conscious appreciation of smell
What is the occipital lobe responsible for?
Vision
What is located on the medial surface of the occipital lobe?
Area 17, primary visual cortex
What are areas 18, 19?
Visual association cortex concerned with interpretation of visual images
What is the limbic lobe responsible for?
Functional area
What is aphasia?
Problem with speech due to damage to one or more speech areas in the brain
What is Broca’s aphasia?
Understands speech but misses small words
Aware of difficulties in speech
Damage to frontal lobe, weakness/paralysis of one side of body
What is Wernicke’s aphasia?
Fluent speech with new words added
Unaware of mistake
Damage to temporal lobe
What are commissural fibres?
Connect corresponding areas of the two hemispheres
Found in corpus callosum
What are association fibres?
Connect one part of the cortex with the other
May be short or long
What are projection fibres?
Run between the cerebral cortex and various subcortical centres
Pass through corona radiate and internal capsule
What is the internal capsule?
Made up of projection fibres passing to and from the cerebral cortex
Narrow area between the thalamus and caudate nucleus medially and lentiform nucleus laterally
What does the internal capsule derive blood supple from?
Middle cerebral artery
What is the basal ganglia?
Subcortical nuclei deep within each cerebral hemisphere
What composes the basal ganglia?
Caudate nucleus, putamen and globus pallidus
What is the major function of the basal ganglia?
Help regulate initiation and termination of movements
What are the input regions of the basal ganglia?
Caudate nucleus and putamen
Receive input from motor cortex, premotor cortex and thalamus
What are the output regions of the basal ganglia?
The globus pallid us and substantia nigra
Where does the globus pallidus project?
Thalamus which then sends fibres to motor area of cortex
