Neuroanatomy Flashcards
What is the brain stem composed of?
The combination of midbrain, pons and medulla oblongata
What is a neuron?
The “Communicators”. They receive information, chiefly via synapses, integrate the information, and then transmit electrical impulses to another neuron or effector cell.
What is a neuron made up of?
A neuron has three main parts: dendrites, an axon, and a cell body or soma, which can be represented as the branches, roots and trunk of a tree, respectively.
What is the role of astrocytes?
Roles in support, maintaining the blood-brain barrier, environmental homeostasis. Astrocytes are the most numerous cell type within the CNS
What are oligodendrocytes?
Produce myelin in the CNS (NOT IN THE PNS). Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity.
What are microglia?
Cells of similar lineage to macrophages (i.e., hemopoietic origin). Immune monitoring and antigen presentation.
What are ependymal cells?
Ciliated cuboidal/columnar epithelium that lines the ventricles.
Type of neuronal support cell (neuroglia) that forms the epithelial lining of the ventricles (cavities) in the brain and the central canal of the spinal cord.
What is the grey matter of the brain?
Home to neural cell bodies, axon terminals, dendrites, and nerve synapses. This brain tissue is abundant in the cerebellum, cerebrum, and brain stem. It also forms a butterfly-shaped portion of the central spinal cord.
What is the white matter of the brain?
White matter is found in the deeper tissues of the brain (subcortical). It contains nerve fibres (axons), which are extensions of nerve cells (neurons).
What are the fissures of the brain?
A fissure is a deeper grove and is often used interchangeably with sulcus. Each cerebral hemisphere divides into four separate lobes by a central sulcus, parieto-occipital sulcus, and lateral fissure.
What are the gyrus of the brain?
A gyrus (plural: gyri) is the name given to the bump’s ridges on the cerebral cortex (the outermost layer of the brain).
What are the sulcus of the brain?
A sulcus (plural: sulci) is another name for a groove in the cerebral cortex.
What are the roles of the gyri and sulci?
Each gyrus is surrounded by sulci and together, the gyri and sulci help to increase the surface area of the cerebral cortex and form brain divisions.
Difference between sulcus and fissure?
A fissure separates one lobe from another, while a sulcus is within a lobe and determines the boundaries of the gyri.
What is the lateral ventricle?
The two largest ventricles of the brain and contain cerebrospinal fluid (CSF).
Each cerebral hemisphere contains a lateral ventricle, known as the left or right ventricle, respectively.
What is the thalamus and its role?
The thalamus is composed of different nuclei that each serve a unique role, ranging from relaying sensory and motor signals, as well as regulation of consciousness and alertness.
What is the lentiform nucleus?
The lentiform nucleus is a collective name given to the putamen and globus pallidus, both of which are nuclei in the basal ganglia - As part of the basal ganglia, it carries out complex functions related to movement, cognition, and emotion.
What is the basal ganglia?
A group of subcortical nuclei responsible primarily for motor control, motor learning, executive functions, behaviours, and emotions. Disruption of the basal ganglia network forms the basis for several movement disorders.
Corpus callosum
The primary commissural (joining/junction) region of the brain consisting of white matter tracts that connect the left and right cerebral hemispheres.
Internal capsule
A white matter structure composed of bundles of myelinated fibres that course past the basal ganglia.
It separates the caudate nucleus and thalamus from the lentiform nucleus.
What is the midbrain?
The midbrain serves important functions in motor movement, particularly movements of the eye, and in auditory and visual processing.
What are the pons?
Connect the medulla with the cerebellum.
Works together with the medulla oblongata to serve an especially critical role in generating the respiratory rhythm of breathing.
Medulla?
It plays an essential role in passing messages between your spinal cord and brain. It’s also essential for regulating your cardiovascular and respiratory systems.
What is the pineal gland?
the “Seat of the Soul”, and it is located in the center of the brain. Receives information about the state of the light-dark cycle from the environment and convey this information to produce and secrete the hormone melatonin.
Function of the frontal lobe?
The frontal lobes are considered our behaviour and emotional control centre and home to our personality.
Function of the temporal lobe?
The second largest lobe. They are most commonly associated with processing auditory information and with the encoding of memory. Language as well.
o Recognition deficits (agnosias)
Function of the occipital lobe?
Smallest of the four lobes. The occipital lobe is primarily responsible for visual processing. It contains the primary and association visual cortex.
o Visual field defects
Function of the parietal lobe?
Process somatosensory information from the body; this includes touch, pain, temperature, and the sense of limb position. Like the temporal lobes, the parietal lobes are also involved in integrating information from different modalities.
What are the three meninges layers from superficial to deep
Dura mater - outermost layer
Arachnoid mater - middle layer
Pia mater - is the delicate innermost layer of the meninges, the membranes surrounding the brain and spinal cord.
What is the cerebellum?
The cerebellum is important for making postural adjustments in order to maintain balance.
What does the anterior cerebral artery supply?
The anterior cerebral artery (ACA) is one of a pair of cerebral arteries that supplies oxygenated blood to most midline portions of the frontal lobes and superior medial parietal lobes of the brain.
What does the middle cerebral artery supply?
It supplies blood to lateral (side) areas of the frontal, temporal, and parietal lobes.
What does the posterior cerebral artery supply?
Supply the posterior medial parietal lobe, inferior and medial part of the temporal lobe including the hippocampal formation, and the medial and inferior surfaces of the occipital lobe.
What is the spinal cord?
The spinal cord is the caudal continuation of the brainstem. It commences at the foramen magnum and traverses the vertebral foramen to the lower border of the first lumbar vertebra (L1) in an adult
What are the two tracts of the spinal cord called?
the ascending (towards brain) and descending tracts (away from brain) of the spinal cord
What is the end of the spinal cord called and where is it?
As the spinal cord approaches its most inferior limit, it tapers off to form the conus medullaris. At the inferior border of L1, a filamentous extension of the spinal cord known as the filum terminale is continuous caudally, to the point of insertion at the coccyx.
What is present at the lumbar enlargement?
The spinal nerves arborize to form the cauda equina
The spinal cord is divided into a white and grey matter like the brain, what is the grey matter of the spinal cord?
Butterfly-shaped collection of neuronal cell bodies.
It is subdivided into the dorsal (posterior), intermediate (lateral), and ventral (anterior) grey columns (horns).
What is the white matter of the spinal cord and how is it arranged?
Collection of myelinated nerve fibres that travel to and from the brain. Like the grey matter, it can be subdivided into anterior (ventral), posterior (dorsal), and lateral segments called funiculi (s. funiculus).
The dorsal funiculus is unique as it can be divided into two fasiculi; what are they called?
The gracile fasciculus (fasciculus gracilis) and the cuneate fasciculus (fasciculus cuneatus)
How many pairs of spinal nerves are there?
31 pairs
What are the two enlargements of the spinal cord?
Cervical, which is related to the upper limb, and lumbar, which is related to the lower limb.
What is the conus medullaris?
The distal tapering end of the spinal cord at L1 - This structure serves to stabilize the spinal cord by connecting the conus to the coccyx via the coccygeal ligament.
What is the Filum terminale?
The fibrous extension of the cord, the filum terminale, is a nonneural element that extends down to the coccyx.
What are cisterns?
Enlarged pockets of CSF created due to the separation of the arachnoid mater from the pia mater based on the anatomy of the brain and spinal cord surface.
The butterfly shaped grey matter of the spinal cord is divided into 4 sections; what are they?
Left and right posterior (dorsal) horn - sensory
Left and right anterior (ventral) horns - motor