Cerebral Cortex: Cells and Function Flashcards
What is different about unmyelinated axons with examples?
- they are shorter and thinner than myelinated axons
- they do not have a Node of Ranvier so they are slow conducting
- they are sensory fibres that carry pain, itch and temperature
Describe features of MS
- abnormal immune response which affects the CNS
- causes inflammation mediated by T cells and macrophages
- causes damage to myelin and oligodendrocytes slowing conduction
- results in permanent axonal loss and cell death
- can have some remyelination due to natural healing by stimulating oligodendrocytes to make more myelin (slow)
Name the glial cells of the CNS and PNS with their functions
CNS:
- oligodendrocytes (myelination)
- astrocytes (metabolic and mechanical support - water distribution, K+ buffering, maintain BBB, ROS scavenging)
- microglia (macrophage - phagocytosis, antigen presenting, synaptic pruning)
- ependyma (ciliated cuboidal epithelial cells - produce CSF)
PNS:
- Schwann cells (myelination)
- satellite cells (support cells in ganglia)
Name the glial cells of the CNS and PNS with their functions
CNS:
- oligodendrocytes (myelination)
- astrocytes (metabolic and mechanical support - water distribution, K+ buffering, maintain BBB, ROS scavenging)
- microglia (macrophage - phagocytosis, antigen presenting, synaptic pruning)
- ependyma (ciliated cuboidal epithelial cells - produce CSF)
PNS:
- Schwann cells (myelination)
- satellite cells (support cells in ganglia)
Describe the neurons that form the layers of the cerebral cortex, their communication and layer order
Cells:
- satellite interneuron (granular layers, responsible for input and processing (sensory))
- pyramidal neurons (pyramidal layers, responsible for output (motor))
Layers:
- molecular layer
- external granular
- external pyramidal
- internal granular
- internal pyramidal
- multiform layer
Describe how information is carried in the association visual cortex
Ventral stream for vision for action in the conext of movement (inferior temporal lobe): integrates motion vs object location
Dorsal stream for vision perception and visual memory (posterior parietal lobe): distinguishes spatial patterns, objects, faces
What is the location of the primary visual, motor and sensory cortices?
- primary visual: occipital lobe
- primary motor: pre-central gyrus (frontal lobe)
- primary somatosensory: post-central gyrus
What are the motor association cortex regions and their functions?
Supplementary motor area:
- responds to mental rehearsal of sequences of movements
- bilateral movement
Pre-motor cortex:
- preparation for action
- posture/gait
- integrates spatial info, planned movement, grasping
Posterior parietal cortex:
* integrates spatial representation of objects for action planning and control (integrates visual info to formulate a motor command)
Distinguish between primary and association areas of the cerebral cortex
Primary cortex:
- performs task
- takes in sensory information and sends out motor information
Association cortex:
- bigger than the primary cortex
- integrates information from the primary cortex to allow for analysis and recognition
- allows action on a sensory input with respect to past experiences
What is the role of the pre-frontal region?
- attention
- morality
- planning
- working memory
- social behaviour regulation
What are the areas of the brain significant of language?
Broca’s area (execution of language):
- left hemisphere, inferior frontal lobe
- regulates breathing patterns when speaking
Wernike’s area (understanding language):
- left hemisphere, temporal lobe
- language development and comprehension
Connected by the arcuate fasciculus
Describe cerebral dominance
- hemispheric specialisation
- has the ability to switch sides in the context of trauma/damage due to neuroplasticity by reorganising its structure/function/connections
