Intensive 1 Flashcards
What are the structural / anatomical divisions of the Nervous System
Structural / anatomical divisions include:
- The central nervous system (Brain, brainstem, cerebellum, spinal cord).
- The peripheral nervous system (Cranial nerves and their ganglia + spinal nerves and their ganglia
What are the functional classifications of the nervous system?
Functional classifications of the nervous system include sensory (afferent) and motor (efferent) divisions.
Each functional branch (sensory & motor) contains nerves that either detect sensory information or deliver motor signals to either somatic tissue (muscles etc involved in voluntary movement) or visceral tissue (organs, glands - involuntary movements / secretions).
The visceral efferent system is also called the autonomic nervous system (ANS = Parasympathetic + Sympathetic)
Additionally the visceral tissues receive both sympathetic and parasympathetic input. Grossly speaking parasympathetic inputs increase visceral functions such as digestion and decrease voluntary movement associated functions; where as sympathetic input decreases visceral functions such as digestion and increase somatic associated functions (ie respiratory rate, heart rate etc).
What is the general role of the afferent (sensory) division somatic nervous system?
The general role of the afferent somatic nervous system is to detect changes in the external environment.
Afferent somatic receptors detect change in the external environment > convey change to CNS > response issued as determined (often delivered via efferent somatic signals).
For example:
Afferent somatic receptors detect heat on hand that touches hot surface > sensory input conveyed to CNS > efferent somatic nerves deliver message to muscles of arm / hand to withdraw hand from hot surface.
What is the general role of the visceral afferent (sensory) nervous system?
The general role of the visceral afferent nervous system is to detect changes within the internal environment.
For example distension of the digestive tract is detected by visceral afferent nervous system which conveys stimuli to the CNS > CNS responds via the autonomic NS (parasympathetic or sympathetic) > the visceral efferent may respond to promote digestion / peristaltic contraction to promote digestion.
At it’s most basic / fundamental level, what is the role of the nervous system?
The most basic / fundamental function of the nervous system is to detect (afferent division) changes in our environment (both external to the body and internally) > to process this information in the CNS > to respond to changes as required (efferent division).
What does the term ganglia refer to?
Ganglia are collections of peripheral nerve cell / neuron cell bodies. (PNS = outside of CNS)
What is another more common term for the Visceral efferent nervous system?
The Autonomic nervous system describes the visceral efferent nervous system. It has two divisions; the Parasympathetic and the sympathetic divisions.
In general terms, what is the roles of the two divisions of the Visceral efferent (motor division) of the nervous system (commonly known as the Autonomic nervous system - ANS)?
Parasympathetic: ‘Rest and digest.’
Sympathetic: ‘Fight, flight, fright.’
What constitutes the grey and white matter of the brain?
The grey matter in the brain contains neuronal cell bodies (neurons cell bodies, dendrites & neuroglia).
*Synapses occur in grey matter.
The white matter contains no neuron cell bodies but millions of axons and neuroglia).
*White matter connects different parts of the CNS
Label the basic brain structures image attached
Cerebrum (R & L cerebral hemispheres)
Cerebellum
Brainstem (midbrain, pons, medulla oblongata)
Diencephalon (thalamus, hypothalamus)
What is the grey matter sheets called that line the outer layer of the (i) cerebral hemispheres; & (ii) the cerebellum
The grey matter / sheets forming the outer layer of the cerebrum and cerebellum are called:
(i) the cerebral cortex
(ii) the cerebella cortex
Label the ventricles of the brain in the image attached.
What are the three types of white matter?
The three types of white matter include (i) Association fibres, (ii) Commissural fibres and (iii) Projection fibres.
What is the role of white matter: commissural fibres?
Commissural fibres connect the R & L cerebral hemispheres for example the Forceps Major in the posterior aspect of the brain connects the R & L Occipital lobes.
What is the role of the white matter association fibers?
Association fibres connect different parts of the same cerebral hemisphere with each other.
There are two types of association fibres (short and long). Short connect within the same gyrus and long connect distant regions of the same lobe, such as the Arcuate fasiculus, Superior longitudinal, Inferior longitudinal fibres and the Uncinate fasiculus.
What is the largest commissural fibre region in the brain?
The Corpous Callosum
It connects all the parts of the R & L cerebral hemispheres (except the anterior and inferior parts of the temporal lobe).
What is the role of white matter projection fibres?
The role of projection fibres (white matter) is to connect higher brain centres to lower centres. For example the internal capsule which contains the cortico-spinal track (cortex > spinal cord).
There are ascending and descending projection fibres.
Projection fibres connect the cortex to ie, brainstem, cerebellum and spinal cord.
What is the role of the Arcuate fasiculus
The Arcuate fasiculus is a long association fibre (white matter) that connects Wernike’s area with Broca’s motor and speech area.
What does the brain consist of?
(i) Neurons; grey matter (neuronal cell bodies) & white matter (neuronal axons),
(ii) Neuro glial cells (support cells ie astrocytes)
(iii) the ventricular system
What sections of the brain stem is connect to the cerebellum posteriorly?
All three sections of the brain stem (midbrain, pons & medulla oblongata) are connected to the cerebellum posteriorly.
Which part of the brain stem continues into the spinal cord?
The medulla oblongata, the most inferior part of the brain stem extends inferiorly to become the spinal cord.
Label the following diagram and explain the fundamental purpose of this anatomical structure for the cerebral hemispheres.
The elevations are called gyri and the groves are called sulci. They function to increase brain surface area.
Label the main gyri of the cerebrum.
The main gyri of the cerebrum include the central sulcus, the occipital sulcus and the lateral sulcus (Sylvian Fissure).
Which sulcus divides the frontal and parietal lobes of the cerebrum?
The central sulcus divides the frontal and parietal lobes of the cerebrum.
The central sulcus lies between which two cerebral lobes?
The central sulcus lies in between the frontal and parietal lobes.
What is the name of the sulcus which lies between the parietal and occipital lobes of the cerebral hemispheres?
The parieto-occipital sulci lies between the parietal and occipital lobes of the cerebral hemispheres.