Central nervous system Flashcards
What forms the CNS?
Brain and spinal cord
What is the function of the brain?
Where afferent neurones are processed, form where instruction can be issued as required to provide complete coordinate response through efferent descending tract of neurones
What are the three distinct areas of the brain?
Forebrain, mind brain and hind brain
What is the forebrain?
Cerebral hemispheres. and diencephalon
What is the hindbrain?
Cerebellum, pons and medulla
What forms grey matter?
Cell bodies
What forms white matter?
Nerve fibres
Which tracts decussate at the medulla as they leave the brain?
Dorsal columns
Corticobulbar
Corticospinal
What separates the cerebrum into two cerebral hemispheres?
Longitudinal fissure
What is the cerebral cortex?
Represents the outer layer of the cerebrum, consists entirely of grey matter- cell bodies, dendrites and synapses
What connects the two cerebral hemispheres together?
Band of axons (white matter) = corpus callous
What are the four main lobes of the cerebral hemispheres?
Frontal, parietal, temporal and occipital
What is the frontal lobe associated with?
Higher brain functions - emotional responses, planning, reasoning and decision making
Regulating and initiating motor function, language, attention and memory
What is the parietal lobe associated with?
Sensory movements (touch, pain), understanding spatial orientation and cognition. Sensory aspects of language
What is the occipital lobe associated with?
Controls range of visual functions: shape recognition and colour vision
What is the temporal lobe associated with?
Vision, memory, language, and comprehension
Processing auditory function
What is the limbic lobe associated with?
Amygdala, hippocampus, maxillary body and cingulate gyrus
What is the function of the hippocampus?
Responsible for the consolidation of learning from short term to long term
What is the mammillary body associated with?
Recollective memory
what is the limbic system concerned with?
Memory, emotion, motivation, reward and learning
Where is the insular cortex located?
Located in each cerebral hemisphere, deep within the lateral sulcus
What is the lateral sulcus?
Tissue separating the temporal lobe from parietal and frontal lobes
What is the insular cortex associated with?
Visceral sensations, autonomic control, interoception, auditory processing and visual-vestibular integration
What is visual vestibular integration?
Balance of eye movements
What is interoception?
Internal recognition
What three layers form the meninges?
Dura mater, arachnoid, and pia mater
Where does the subarachnoid space lie?
Between the arachnoid and Pia mater
What layers consist of the dura mater?
Periosteal and meningeal
What is the periosteal layer?
Layer of periosteum, lines internal cranium,
What is the meningeal layer?
Dural, dense fibrous membrane
Thick membrane consisting of dense irregular connective tissue, surrounding the brain and spinal cord.
What is the purpose of the subarachnoid space?
Contains cerebrospinal fluid
What is pia mater?
Thin, translucent & mesh like. Highly vascular membrane, closely adherent to the surface of the brain
Where is CSF produced?
Choroid plexus
Where is the choroid plexus located?
Lateral 3rd and fourth ventricles
Where does the CSF occupy?
Occupies the ventricular system, subarachnoid space, cisterns and central canal of the spinal cord
How is CSF reabsorbed?
Arachnoid villi (granulations) into superior sagittal sinus
Which foramen enables transpiration of CSH to the third ventricle?
Foramen of monroi
What is the foramen Lushcka?
Facilitates movement of the fluid into the subarachnoid space
What are the comparisons between CSF and plasma?
Lower pH, less glucose and potassium
Clear fluid- absent of blood and proteins
How can CSF be used as an indicator for pathological disease?
Protein blood detection in CSF
Which nerves are carried by the posterior ramus?
Visceral motor somatic motor and sensory nerves