Nervous System Anatomy Flashcards
What are some of the main functions of the nervous system?
- Communication
- Regulation of internal events
- Storage of information
- Behavioural organisation
- Sensations, perceptions, emotions
- Make us who we are, how we feel and move in the world
What segments can the nervous system be split into?
- Central: -brain and spinal cord
- Peripheral: - spinal nerves (come off spinal cord) and cranial nerves (come off brain and brain stem)
What does sensory info come through to go into the spinal cord?
- Somatic afferents (sensory info coming from body)
- Visceral afferents (sensory info coming from visceral organs)
What happens to sensory info once it reaches the spinal cord?
It travels up to the brain to be processed then comes back down the spinal cord to be released as motor info.
What does motor info travel through to get to desired area?
- Somatic efferents (for info going to skeletal muscle)
- Visceral efferents (for general info and info going to smooth muscle, cardiac muscle and glands)
What is there between going from spinal cord to visceral efferents?
A synapse in between the 2 fibres.
What is the brain separated into on the surface?
2 cerebral hemispheres separated by longitudinal fissure (a groove in the middle)
What things make up the cerebrum?
- Gyri (ridges) and sulci (grooves), these give the characterisitc folded appearance
- Outer grey layer and an inner white matter
What is the purpose of the gyri and sulci?
They increase surface area meaning more nerve fibres can be in the brain and it helps in the limiting cavity of the skull.
What is the function of the cerebellum?
Controls movement, specifically co-ordinating movement and precision with integration of the sensory system.
What is the brainstem comprised of?
Midbrain, pons and medulla.
What is the function of the brainstem?
Breathing
Heart rate
What parts of the brain make up the forebrain?
Telencephalon (cerebrum)and diencephalon(thalamus and hypothalamus)
What makes up the midbrain and what is its function?
Mesencephalon is the midbrain
Plays role in vision, hearing, motor function and arousal state
What makes up hindbrain?
Rhombencephalon
What are glia?
Non neuronal cells of the brain and nervous system?
What are examples of glia and their function?
- Astrocytes=involved in nutrient supply to neurons in the CNS
- Ependymal cells= involved in production eg.CSF
- Oligodendrocytes= neuronal support and myelin formation in the CNS
- Schwaan cells= neuronal support and myelin formation in PNS
What is the central canal of the spinal cord surrounded by?
Ependymal cells
What does homunculus show?
How diproportionate areas of the sensory and motor function are represented in the brain.
Eg. bottom of body represented by top of brain
What 4 lobes can the brain be split into?
- Frontal
- Occipital
- Parietal
- Temporal
What is the function of the frontal brain lobe?
Long term memory, speech, movement, personality
What is the function of the parietal brain lobe?
Sensory integration, language interpretation, spatial/visual perception
What is the function of the occipital brain lobe?
Visual processing (colour, light)
What is the function of the temporal brain lobe?
Primary auditory cortex, memory, understanding language
What is the corpus callosum and its function?
Right and left cerebral hemispheres joined by corpus callosum.
Fibres cross over the body, so opposite side of brain controls opposite side of body.
It is linked to cognitive function
How is the spinal cord arranged?
Into cervical, thoracic, lumbar, sacral and coccygeal parts.
Where is the conus medullaris?
At lower end of spinal cord at L1-L2.
What is the cauda equina?
Nerve rootlets at L2-L5, CSF can be extracted from here in the subarachnoid space. It sits in the lumbar cistern formed by the subarachnoid space.
Cauda equina extends from conus medullaris to S2.
What is the meninges made up of?
3 layers that wrap around brain and spinal cord
Dura
Arachnoid
Pia
Describe the dura
thick membrane and made of dense irregular connective tissue.