NERVOUS SYSTEM: INTRODUCTION Flashcards
define: axon
extends into cell body and carries exciatory output in the form of action potentials
define: dendrites
receive input
define: cell body (soma)
contains genetic information, maintains the neuron’s structure, and provides energy to drive activities
define: neuroglia
differ from neurons in several ways; do not form synapses, have only one type of projection, are able to divide, and are less electrically excitable
define: pia mater
Pia mater: inner layer of the membrane surrounding the brain
What are the major divisions of the central nervous system
brain and spinal cord
what are the major divisions of the peripheral nervous system and their function
Peripheral nervous system (PNS): sensory afferents, somatic motor efferents, autonomic efferents
Afferent pathways of the PNS deliver sensory input to the CNS
Somatic efferent pathways control voluntary/skeletal muscle
Autonomic efferents control smooth and cardiac muscle
Explain the organization of the peripheral nervous system where it interfaces with the central nervous system
Interfaces with the central nervous system in the dorsal and ventral horns of the spinal cord
- dorsal horn: transmit sensory information from the peripheral nervous system to the central nervous system
- ventral horn: send axons via the ventral roots of the spinal nerves to terminate on striated muscles.
What does the ascending dorsal column medial lemniscus carry and where?
carries sensory input on fine touch, vibration and proprioception to the brain
What does the Ascending spinothalamic pathway carry and where?
carries sensory input on temperature, crude touch and pain to the brain
What does the corticospinal tracts carry and where?
carry motor signals from the brain to skeletal muscles to control movement (also called pyramidal and extrapyramidal)
What does the antero-lateral pathways carry and where?
pain and temperature up to the brain
What are the functions of the CNS? (5)
- Gather and integrate information from PNS
- Process and perceive information from PNS
- Organize reflex and autonomic responses
- Planning and executing voluntary movements
- Higher functions like cognition, learning and memory
Define/ give the function of: frontal lobe
Frontal lobe: primary motor cortex
Define/ give the function of: temporal lobe
Temporal lobe: auditory cortex and auditory association area
Define/ give the function of: parietal lobe
Parietal lobe: primary somatosensory cortex and sensory association area
Define/ give the function of: occipital lobe
Occipital lobe: visual association area, visual cortex
Explain the utility and limitations of Brodmann Areas
- Useful in that many areas associate closely with diverse functions (e.g. BA 1-3 is the sensory cortex; A4 is the motor cortex)
- Functional imaging can only identify approximate areas in terms of BAs because definition of the boundaries between them requires histological examination
- dated and debated
Define: cerebral cortex and give the function of its 3 layers
the outer layer that lies on top of your cerebrum
- superficial layers: have connections with other cortical areas
- intermediate layers: receive input from subcortical areas
- deep areas: project to subcortical areas
Cell layer composition and thickness varies across areas of the brain and can be used to divide cortex into Brodmann areas
What are cortical columns?
Six-layered functional networks; make up the basic ‘processing module’ for the cerebral cortex
The cellular makeup, together with their input and output connections, define the function and activity of the local region
define and give the function of thalamus
subcortical gray matter structure that acts as a ‘relay’ for sensory and motor information
define and give the function of the basal ganglia
subcortical gray matter structure involved in movement processing
gustatory complex
taste
olfactory complex
smell
sensorimotor and premotor cotex
motor coordination
dorsolateral prefrontal and lateral orbitofrontal cortex
planning and execution
limbic and paralimbic cortex, hippocampus, and amygdala
emotion
cerebrum
Cerebrum: cognition, motor control, sensory processing, language processing, memory formation
cerebellum
Cerebellum: motor coordination, balance and posture, cognitive functions, emotions and behaviour
brainstem
Brainstem: regulation of breathing, heart rate, swallowing and gag reflex, vomiting and coughing, alertness, cranial nerve function
