Structure of the Nervous System Flashcards
What are the terms used to describe directions in the brain?
Dorsal: Top of brain
Ventral: Bottom of brain
Anterior: Front of brain
Posterior: Back of brain
Medial/Lateral: Middle Sides
Coronal Section: A cut from the
vertical plane from the crown of the head down and yields a frontal view
Horizontal Section: Falls along the horizon, viewed looking down from above (dorsal view)
Sagittal Section: A cut lengthways, front to back, and viewed from side (medial view)
What are the 2 divisions of the nervous system.
They are called the central and peripheral nervous systems
What does the the Central Nervous System contain?
The CNS contains the Brain and the spinal cord
What does the Peripheral Nervous System Contain?
The Autonomic Nervous System and the Somatic Nervous System
What does the Somatic Nervous System do?
Efferent Nerves: outgoing motor nerves that connect the CNS to the skeletal muscles
Afferent Nerves: incoming sensory nerves that carry information from sense organs into the CNS
What does the Autonomic Nervous System do?
Sympathetic nervous system: Arouses body to expand energy. “Fight or flight”
Parasympathetic nervous system: Calms body to conserve and mantain energy “ rest and digest”
What is the cerebrum?
It is a major structure of the forebrain which has 2 identical forebrains?
What does the cerebellum do?
The cerebellum is involved in motor coordination and possibly other mental processes.
What does the brainstem do?
The brainstem connects the brain to the spinal cord. it is critical for sustaining life (respiration, blood pressure, etc}
Basic instinctual function
What is the Cerebral Cortex?
It is the outer layer of grey matter which allows us to be conscious. It has a wrinkled appearance.
Gyrus?
a bump or convulsion between grooves
Sulcus?
A groove between gyri
What are the Lobes of the brain? What does each one do?
-Frontal Lobe: Controls motor control and executive functions
-Occipital Lobe: Controls vision
Parietal Lobe: Controls touch sensation and self of sense in space
Temporal Lobe: Controls auditory sensation, language perception, and taste functions.
What is the corpus callosum?
The corpus callosum connects the cerebral hemisphere so both sides of brain can work together
What is the Diencephalon and what does it do?
The diencephalon is one of 3 basic regions in the brainstem. It contains;
Thalamus: all sensory information (except smell) that passes through the thalamus
Hypothalamus: Controls homeostasis, regulates hormone secretion and maintains control of the brain
What is the Midbrain and what does it do?
The Midbrain is another one of the 3 basic division of the brainstem. The Midbrain contains neurons that the
What is the Hindbrain and what does it do?
The hindbrain is the last of the 3 basic regions of brainstem and it consists of ;
Pons: Connects the cerebellum to brain
Medulla: Controlls breathing and heart rate, connects brain to spinal cord, most inferior ventral portion of brain
What is the Ventricular System?
The brain is cushioned and supported by a series of interconnected hollow spaces called ventricles
What do meninges do?
Meninges are special membranes that protect the brain
What is Cerebrospinal Fluid?
CSF fills ventricles, brain, and spinal cord. Possesses a similar density to the brain to float comfortably in skull.
What are blood brain barriers?
Tight gaps between endothelial cells that prevent large molecules passing into the brain
What are the 2 main types of brain cells
-Neurons: the basic information processing units, second most populous in brain
-Glial Cells: Supports and modulates the neurons activities, creates the myelin sheath, most populous cell in brain
What do dendrites do?
They gather information from other neurons
What is the cell body?
It is the core region of neuron, contains the nucleus
What is the axon hillock?
connects the axon to cell body, is where the action potential begins
What is an Axon?
the axon carries information to be passed on to other cells
What is the terminal button?
knob at tip of an axon that conveys information to other neurons
What is Myelin/ Myelin Sheath?
a fatty substance produced by glial cells, it insulates the axon which increases speed and efficiency of electrical signal conduction
Schwann cells myelinate axons in PNS
Oligodendrytes myelinate axons in CNS.
Nor all axons are myelinated
What is Grey Matter and White Matter?
Grey Matter are the areas of the nervous system composed of cell bodies and blood vessels
White Matter is areas of the nervous system rich in fat-sheathed neural axons
What are tracts?
Large collections if axons in the CNS, they connect nuclei to each other in the brain, white matter mostly consists of tracts
What is a Nerve?
A large connection of axons forming connections in the PNS
What is a Nucleus?
A distinct cluster of neural cell bodies forming a functional group.
How do neurons organize themselves?
Neurons in cortex have uniform organizations
Neurons in subcortical and brainstem nuclei have irregular organization
What system is the Limbic System in?
The subcortical system
What is the Limbic System?
The limbic system:
is important for memories and can be effected by psychological disorders and drugs.
Consists of key nuclei in brain to control motivation and emotions.
The limbic system consists of 3 major parts
What is the Cingulate Cortex and what does it do?
The cingulate cortex is one of 3 important parts in the limbic system, it is involved in emotional processing and memory
What is the amygdala and what does it do?
The amygdala is one of 3 major parts of the limbic system. it is involved in fear, aggression, emotionally charged memories.
What is hippocampus and what does it do?
The hippocampus is 1 of 3 major parts of the limbic system. it is volved in formation of long term memories (spatial learning, environmental awareness)
What is the basal ganglia?
The basal ganglia is involved in controlling movement, learning and memory (Motor control and habits).
It consists of 3 main parts
What are the 3 main parts of the basal ganglia?
- The Caudate nucleus and the Putamen.
- The globus pallidus
- The substantia nigra: it is a part of the midbrain
What does the substantia nigra do?
It contains numerous dopamine neurons that project into basal ganglia
