Lecture 20 Flashcards
Where is each lobe of the cerebrum located?
same location as bones, frontal bone as the most anterior, parietal immediately posterior, temporal lobe inferior to parietal, occipital as the most posterior lobe.
What are the names of the sulcuses which seperate the regions of the brain? which regions do they seperate? What are the two most important gyri?
The central sulcus separates the parietal lobe and the frontal lobe, the parieto-occipital sulcus separates the occipital and parietal lobe, The lateral sulcus separates the temporal lobe and the frontal lobe, the transverse fissure acts to seperate the cerebrum from the cerebellum. The two key gyri are the post-central gyrus and the pre-central gyrus.
What are the two types of the motor cortex and what is each part associated with?
The primary motor cortex is located on the pre-central gyrus and controls execution of movement, the pre-motor cortex is found immediately anterior and is involved in the planning of movement. Note that these control our voluntary movement.
What is the prefrontal cortex involves in?
-Decision making, anticipating consequences of actions, emotion.
What parts of the brain are considered to be in the brainstem? Which of these two are considered to be in the hindbrain?
The midbrain, pons and medulla oblongata. The pons and medulla oblongata are considered as in the hind brain.
What parts of the brain are not in the brain stem?
Cerebellum, thalamus, hypothalamus, cerebral cortex and corpus callosum.
Where is the 4th ventricle attachment point to the brainstem?
The dorsal aspect of the pons.
What are the deep nuclei?
a collection of cell bodies within the centre of the brain bulk.
What are the three types of white matter? What seperates them? Give an example for each.
Commisural tracts: axons cross side to side, travelling both ways (cell bodies on either side of this type) E.g corpus callosum.
Projection tracts: axons extend between cortex and other CNS areas, one way E.g the corticospinal tract.
Association tracts: Axons found on the same side within the cerebral cortex, allows communication between brain areas E.g communication between motor cortex and somatosensory cortex.
What is the general layout of the moror cortex in regards to which parts it controls? Why do certain areas take up more space?
Parts that are lower down on the body will be more medially located on the motor cortex, some regions e.g the lips and jaw take up more space than their size would suggest due to the large amount of motor units in that small space.
What is the anatomical layout of the corticospinal tract?
Cell bodies within the primary motor cortex, most axon fibres will cross to the opposite site of the body in the medulla, from this point they will descend until the spinal cord where they will synapse.
What is the parietal lobe’s main function? What part is located at the post centralgyrus and what is its function?
The parietal lobe is involved primarily with our senses and association of those senses, The key player we focus on is the somatosensory area of the parietal lobe, found on the post-central gyrus, this acts to integrate multiple types of sensory information from specific regions of the body.
What is a simple somatic sensory pathway?
sensory information travels from the affected region up dorsal white columns where it travels to the medulla and synapses as well as swaps sides, the signal then travels to the thalamus and synapses with another neuron before traveling further to reach the somatosensory cortex.
What does the homunculus look like for the primary somatosensory cortex?
lower down body parts are more median, parts with more nerves take up more space.
What does the cerebellum act to do in regards to movement?
Compares the wanted movement with the movement that is occuring based on sensory information, adjusts the motor output accordingly to cause the desired movement.
