Nervous System Flashcards
What is the overall role of the NS?
-monitors the internal and external environment
-process this information
-direct behaviour and body processes
What is an interneuron?
-wide variety of neuronal subtypes
-complex physiology
-function in networks
-processing information, generating an output
What is the function of neuroglia?
-local concentrations of neurotransmitters
-supply nutrients
-support/guide neuronal development
-sabilise neuronal network
-improve communication speeds
-provide immunological defence
Name the two conceptual divisions
anatomical
functional
Name the anatomical divisions of the CNS
brain
spinal cords
Name the divisions in the PNS
cranical nerves
spinal nerves
What is a ganglia ?
part of peripheral nervous system, collection of neuronal cell bodies
example- dorsal root ganglion
What is the somatic nervous system?
-voluntary motor nerve fibres
-conducts impulses from the CNS to skeletal muscels
What is the autonomic nervous system?
-involuntary motor nerve fibres
-conducts impulses from the CNS to cardiac muscle, smooth muscle and glands
How complex is the brain?
84 billion neurons
86 billion non neurons
cerebellum is 50%
some neurones 100-300k connections
Name the divisions in the sensory PNS afferent
somatic sensory pathway
autonomic sensory pathway
Name the divisions in the motor PNS efferent
somatic motor pathway
autonomic motor pathways
what are satellite cells?
surround neuron cell bodies located in the PNS
Whats the function of dendrites?
recieve information from other neurons called pre synaptic neurons or environment
Define the function of the soma/cell body
-contains genetic info
-maintain neuron structure
-provide energy
define the function of the axon hillock
processes the incoming signals from other neurons
Define the function of terminal branches
change electrical impulses or action potential within a neuron into chemical messages in the form of neurotransmitters.
Name the types of neuroglia
-astrocytes
-oligodendrocytes
-microglial cells
Name some key components of the meninges
-skull bone
-brain
-venous sinus
-arachnoid vilus
-pia matter
-subarachnoid space
-cranial dura matter
What are the layers of the cranial dura matter?
-Periosteal layer
-meningeal layer
-arachnoid matter
Name the ventricles of the brain
-arachnoid granulations
-lateral ventricles
-3rd ventricle
-choroid plexus of lateral ventricle
-4th ventricle
-choroid plexus of the 4th ventricle
-central canal of spinal cord
What is CSF produced by?
-choroid plexuses tissues of brain
What is the function of CSF?
-protective medium for brain
-nutritive- glucose
-removal of metabolites (urea,lactate)
-provide stablie ionic environment
Name the main gyri and sulci of the brain
-pre-central gyrus
-central sulcus
-post central gyrus
-lateral sulcus
Whats the funtion of gyri and sulculi?
-folding of cerebral cortex
-segregates the brain areas and enhances the surface area and cognitive abilities of the brain
-establishes the borders between the brain lobes
Describe grey brain matter
-neurons
-glial cells
-blood vessels
-no major long fibre tracts
Describe white matter of the brain
-fibre tracts
-information highway
-connects different areas of the brain
-sensory and motor pathways
-ascending/descending
-tract to rest of NS
What pia matter of the meninges?
-protects the NS by containing CSF and cushioning the brain and spine
Describe the function of the arachnoid layer
involved in CSF metabolism via the subarachnoid space
-sits between the dura and pia-avascular membrane
Whats the dura matter?
-surrounds, supports and protects the CNS
-thick and fiborous
What are the three key fibre pathways that stem from white matter?
-corpus collosum
-internal capsule
-association fibres
Whats the function of the corpus collosum?
connects the right and left hemispheres
Whats the function of the internal capsule?
connects higher cortical areas to lower brain and spinal cord
Whats the function of association fibres?
connects cortical areas in the same hemisphere
List the main lobes of the brain
-frontal lobe
-parietal lobe
-temporal lobe
-occipital lobe
-brain stem
-cerebellum
Whats the function of the frontal lobe?
-planning, emotion, mood, behaviour, smell and motor function
What is the function of the parietal lobe?
touch,pain,temp sensation
Whats the function of the temporal lobe?
-hearing
-language
-memory
Whats the function of occipital lobe?
vision
Whats the function of the cerebellum?
balance and coordination
what is the choroid plexus?
a cluster of cappilaries enclosed via the PM then by ependymal cells- type of glial cells, each ventricle produces CSF
What is the function of the insula of the brain?
-concious awareness
-gustation
-cognitive emotional processing
-audio-visual integration
-interoception (autonomic sensory monitoring)
-homeostatic error detection
Whats the structure and function of the brainstem?
-midbrain,pons and medulla oblongata
-ascending/descending nerve tracts
-cranical nerve origin
-contains recticular formation
-conciousness,sleep,gaze centre, modulation of pain, regulation of respiratory and cardiovascular system
Whats the structure of the cerebellum?
-two hemispheres which are connected by the vermis, a narrow midline area
-consists of grey and white matter
Whats the structure and function of recticular formation?
-a diffuse-net like formation of recticular nuclei
Name some specific functional areas of the brain
-motor cortex somatic
-Brocas area
-auditory cortex
-sensory cortex
-visual cortex
-wernicke’s area
Whats the function of the motor cortex somatic?
-motor control of skeletal muscles
Whats the function of Brocas area?
-motor control of speech
-speech planning( stutter)
-motor planning
-language output area
Whats the function of the auditory cortex?
-pitch, loudness, location
-auditory memory/ sound recognition
Whats the function of the sensory cortex?
-input from skin
-input from propioreceptors
-spatial discrimination
Whats the finction of the visual cortex?
mapping visual input
visual recognition
Whats the function of Wernicke’s area?
-language
-reading or listening
-recognition of words
-association with menaings
-context
Whats the language loop model?
1-visual cortex
2-brocas
3-wernickes
Define somatotopy
body maps onto brains surface
Describe the motor homunculus
-a representation of the body parts and its correspondence along the precentral gyrus of the fronal lobe
What is the sensory homunculus?
a representation of the body parts along the postcentral gyrus of the parietal lobe
What is the solar plexus?
makes up part of the prevertebral complex
What is the sympathetic postganglionic transmitter?
noraepinephrine
whats the way to remember the PSNS VS SNS?
P- rest and digest
S-fight or flight
What are the 4 main nuclei involved in the brain stem control of CO?
-solitary nucleus
-pressor area- sympathetic
-nucleus ambiguous
-depressor area-inhibition
what are the 3 main nucei involved in the brain stem control of respiratory function?
-pontine nulei
-ventral respiratory group
-dorsal respiratory group
also recieves input from solitary nucleus
describe the relationship between the adrenal gland and SNS
stress triggers the sympathetic nervous system, promting the adrenal glands to release catecholamines
After the amygdala sends a distress signal, the hypothalamus activates the SNS by sending signals through the autonomic nerves to adrenal glands
describe the vagus nerve in autonomic control
-input of sensory ( stretch chemoreception) information from:
lungs,bladder, circulation system, digestive tract
adjustments made via ANS effectors
decribe the cerebral cortex in autonomic control
1- cerebral cortex
2-limbic system -emotional input
3-hypothalamus-overall integration of ANS
4-brain stem-regulates pupil size, BP, airflow
5-spinal cord-reflexes for urination, defecation
