Introduction to the Nervous System Flashcards
Cortex definition/characteristics
- outer covering of brain
- composition = grey matter
- information generated @ cortex is transmitted to contralateral side
Grey Matter definition/characteristics
- cell bodies and dendrites of neurons
- location:
- @ brain = outer layer
- @ spinal cord = inner layer
White Matter definition/characteristics
- myelin-coated axons of neurons
- location:
- @ brain = inner layer
- @ spinal cord = outer layer
Thalmus definition/characteristics
- location = near center of cranial cavity; L & R thalamus on each side of midline
- subregions = nucleus (cluster of cells)
- thalamus projects ==> cerebral cortex ==> contralateral side of spinal cord
Cerebellum definition/characteristics
- large structure projects ==> thalamus
- olive projects ==> cerebellum
- location: posterior + inferior to brain
Commisure definition
Fibrous tract in the nervous system that crosses the midline and connects two points that are mirror images
Decussation definition
Crossing of axons within the brain stem, passing the midline, and heading to another point in the nervous system.
Homunculus definition
- Scale of human body that illustrates physiologic, psychologic, or other abstract human characteristics or functions
- commonly: abstract human figure that illustrates brain area dedicated to each part of the human body
Somatotopy definition
Topographic association of positional relationships of the body to the functional areas of the cerebral cortex
Synaptic Plasticity definition/characteristics + example
- Patterns of activity ==> physical changes in neurons
- Axon A is near to Cell B ==> Axon A & Cell B repeatedly fire together ==> growth process and/or metabolic changes ==> Axon A efficacy in firing Cell B is improved
- “Neurons that fire together, wire together”
- e.g. Pavlov’s Dog: Connects hearing to salivation
Learning definition/characteristics
- structural modification of nervous system ==> long-lasting changes
Conceptual framework of the nervous system (~how does the nervous system work on a small to large scale?)
Genes ==> Gene expression ==> Proteins ==> Protein pathways ==> Subcellular elements (synapses) ==> Neurons ==> Neural circuits/networks ==> Behavior
Basic components of Neurologic exam
- Mental status exam/psychiatric exam
- Reflex exam
- Sensory Exam
- Motor Exam
- Cranial Nerve Exam
- Examination of Coordination and Gait
Possible neuroanatomical localizations of pathology (8)
- Generalized vs. Localized
- Muscle
- NMJ
- Peripheral Nerve
- Spinal Cord
- Brainstem
- Subcortical = Basal ganglia, cerebellum
- Cortical
Differential dx approach for neuropathology
- VITAMIN C:
- Vascular
- Infectious
- Trauma
- Age-related/degenerative
- Metabolic
- Inflammatory
- Neoplastic
- Congenital
