Gross Brain, Brainstem, & Spinal Cord Flashcards
What is the nervous system divided into?
PNS
CNS
This is the collection of spinal and cranial nerves whose branches convey messages to/from the CNS.
PNS
This includes the brain and spinal cord.
CNS
The brain has multiple subdivisions and is composed of what?
Forebrain
Cerebellum
Brainstem
What is the forebrain composed of?
Cerebral hemispheres
Diencephalon
This lies between the forebrain and the spinal cord.
Brainstem
This type of matter consists of areas containing neuronal/glial cell bodies and dendrites.
Gray Matter
Gray matter is made up of ________, which are collections of cell bodies with a common function.
Nuclei
These are layers of gray matter over other parts of the CNS (i.e., cerebral and cerebellar).
Cortex
This type of matter consists of areas where there is a collection of axons, and many are covered with myelin.
White Matter
What are other terms for white matter?
Fasciculus Funiculus Lemniscus Peduncle Tract
Most tracts have 2 part names, that consist of what?
1st part = location of neuronal cell bodies from which axons originate
2nd part = site the axons terminate
***i.e., Corticospinal tract
This is the term for a ridge of cortical tissue.
Gyrus
This is the term for a groove located between gyri.
Sulcus
This is the term for deep sulci.
Fissures
Folding into gyri and sulci increases the total cortical area and the total number of cortical __________.
Neurons
There are four prominent sulci that divide each cerebral hemisphere into five lobes. What are these sulci?
Central sulcus
Lateral sulcus (fissure)
Parietooccipital sulcus
Cingulate sulcus
This sulcus divides the frontal lobe from the parietal lobe.
Central sulcus
This sulcus divides the frontal and parietal lobes from the temporal lobe.
Lateral sulcus (fissure)
***Very deep so it is also called a fissure!
This sulcus divides the parietal lobe and occipital lobe.
Parietooccipital sulcus
This sulcus divides the limbic lobe from the frontal lobe (lies medially, can only see in hemi brain).
Cingulate sulcus
The two hemispheres are joined by a huge fiber bundle called the…
Corpus Callosum
What is the inferior part of the Frontal Lobe called?
Orbital Part of the Frontal Lobe
What are the boundaries of the Frontal Lobe?
Anterior = Frontal Pole Posterior = Central Sulcus to Cingulate Sulcus Medial = Cingulate Sulcus Lateral = Lateral Sulcus (Fissure)
The Parietal Lobe extends from the Central Sulcus to an imaginary line that connects what?
Parietooccipital Sulcus and the Preoccipital Notch
Medially, the Parietal Lobe is bounded inferiorly by what?
Subparietal Sulcus
Calcarine Sulcus
This lobe is bounded anteriorly by the parietal and temporal lobes on both the lateral and medial surfaces of the hemisphere.
Occipital Lobe
This lobe is a strip of cortex that encircles the telencephalon-diencephalon junction. It is interposed between the Corpus Callosum and frontal, parietal, and occipital lobes.
Limbic Lobe
This lobe curves around to occupy part of the medial surface of the brain, which would otherwise be called the temporal lobe.
Limbic Lobe
The Frontal Lobe contains (SENSORY/MOTOR) areas.
Motor
What makes up the lateral surface of the Frontal Lobe?
Precentral Gyrus
Superior Frontal Gyrus
Middle Frontal Gyrus
Inferior Frontal Gyrus
What does the Precentral Gyrus contain?
Primary Motor Cortex
What is contained in the Precentral Gyrus (other than the Primary Motor Cortex) and portions of the frontal gyri?
Premotor and supplementary motor areas
***Involved with planning and initiating voluntary movements
The Inferior Frontal Gyrus consists of three parts, which are what from anterior to posterior?
Orbital Part
Triangular Part
Opercular Part
This is contained in the Opercular and Triangular Parts of the Inferior Frontal Gyrus, only on the left hemisphere.
Broca’s Area
This is important in motor aspects of written and spoken language.
Broca’s Area
The majority of the Frontal Lobe is occupied by this, and it is involved with executive functions, personality, decision-making, insight, and foresight.
Prefrontal Cortex
What makes up the Parietal Lobe?
Postcentral Gyrus
Superior Parietal Lobule
Inferior Parietal Lobule
The Postcentral Gyrus corresponds to the _______ _______ ________. Involved with processing of tactile and proprioceptive information and sensory localization.
Primary Somatosensory Cortex
***Part of Parietal Lobe
The Inferior Parietal Lobule (one hemisphere, usually left) is involved in what?
Language Comprehension
***Part of Parietal Lobe
The remainder of the parietal cortex functions doing what?
Spatial Orientation
Directing Attention
Describe what the Homunculus is.
A “map” of different parts of the body within the brain. There is a motor component in the Precentral Gyrus and a sensory component in the Postcentral Gyrus. The larger the body part appears means there is more innervation to this area.
What are the general locations for each body part in the Homunculus from superior to inferior?
Feet Legs Arm/Wrist Hand Face Mouth
***More detailed than this, look at slide 12!
What is the Temporal Lobe composed of?
Superior Temporal Gyrus
Middle Temporal Gyrus
Inferior Temporal Gyrus
What makes up the inferior surface of the Temporal Lobe?
Occipitotemporal (Fusiform) Gyrus
The superior surface of the Temporal Lobe, continuing as a small area of the Superior Temporal Gyrus, is the…
Primary Auditory Cortex
This is located on the posterior portion of the Superior Temporal Gyrus (one hemisphere, usually left). It’s important in the comprehension of language.
Wernicke’s Area
What gyri are all a part of Wernicke’s Area?
Superior Temporal Gyrus (posteriorly)
Supramarginal Gyrus
Angular Gyrus
What is the inferior surface of the Temporal Lobe involved in?
Higher-order processing of visual information
What is the most medial part of the Temporal Lobe involved in?
Learning and memory
What are the Limbic structures mostly composed of?
Cingulate Gyrus
Parahippocampal Gyrus
The anterior end of the Parahippocampal Gyrus hooks backward on itself forming a medial bump, which is called the…
Uncus
***In Temporal Lobe
Folded in the Temporal Lobe at the Hippocampal Sulcus is the…
Hippocampus
This is important for fear and emotion, and it lies beneath the Uncus of the Temporal Lobe.
Amygdala
This lobe is important in emotional responses, drive-related behavior, and memory.
Limbic Lobe
This area of the brain is an additional area of cerebral cortex not included in the five lobes. It lies buried in the Lateral Sulcus, and you have to pull it back like curtains.
Insula
The Insula can be seen by prying open the Lateral Sulcus or by removing the _________. This is the portion of the given lobe that is overlying the Insula.
Opercula
***There is a Frontal Opercula, Parietal Opercula, and Temporal Opercula because they all cover the Insula
This sulcus outlines the Insula and makes its border with the Opercular areas of the cortex.
Circular Sulcus
What is the Insula important for?
Taste
The lateral surface of the Occipital Lobe contains what gyri?
Lateral Occipital Gyri
This is a wedge-shaped area between the Parietooccipital and Calcarine Sulci (in Occipital Lobe).
Cuneus
***Most superior
This is contain in the walls of the Calcarine Sulcus (in Occipital Lobe).
Primary Visual Cortex
What function is the Occipital Lobe responsible for?
Higher order processing of visual information
This is only viewable in the hemisections of the brain, and includes the thalamus, hypothalamus, epithalamus, and subthalamus.
Diencephalon
This is located by the Optic Chiasm and connects the Pituitary Gland to the Hypothalamus.
Infundibulum (Infundibular Stalk)
The inferior surface of the hypothalamus is visible on an intact brain, including the infundibular stalk and two rounded protuberances called…
Mammillary Bodies
This is the primary processor of sensory information. Everything except olfaction goes through this!
Thalamus
These are a group of nuclei the lie deep to the cerebral cortex in each hemisphere.
Basal Nuclei
***Also called Basal Ganglia
What are the nuclei included in the Basal Nuclei?
Caudate Nucleus
Lenticular Nucleus
The Lenticular Nucleus can be subdivided into what?
Putamen
Globus Pallidus
The Lenticular Nuclei are physically separated from the thalamus and Caudate Nucleus by a thick sheet of fibers called the…
Internal Capsule
This contains most of the fibers interconnecting the cerebral cortex and deep structures (thalamus, basal nuclei, and brainstem).
Internal Capsule
These fibers connect cortical areas within the same sulci/gyri.
Arcuate Fibers
These connect cortical areas within the same hemisphere.
Longitudinal/Association Fasciculi
These connect cortical areas within other body regions.
Projection Tracts
This interconnects the two cerebral hemispheres and contains somewhere around 250 million axons.
Corpus Callosum
This is composed of commissural fibers that go to and from the Temporal Lobe (especially inferior parts).
Anterior Commissure
This is a white matter structure divided into limbs, each containing specific fiber groups.
Internal Capsule
What are the limbs of the Internal Capsule?
Anterior limb Genu Posterior limb Sublenticular limb Retrolenticular limb
This plays a major role in cranial nerve function, and conveys into to/from the forebrain.
Brainstem
This portion of the brainstem houses the tectum, superior and inferior colliculi, and paired cerebral peduncles.
Midbrain
These are paired bumps that are posterior the cerebral aqueduct.
Superior and inferior colliculi
The Basal Pons are part of the Brainstem, and the posterior portion of the pons is called the __________. This makes up part of the floor of the 4th ventricle.
Tegmentum
This part of the brainstem contains a rostral open portion and a caudal closed portion.
Medulla
The rostral open portion of the Medulla contains part of the…
4th ventricle
The caudal closed portion of the Medulla is continuous with what?
Spinal Cord
This functions in sensory information processing and influences motor neurons. Damage to it will result in abnormalities of equilibrium, postural control, and coordination of voluntary movements.
Cerebellum
The surface of the Cerebellum is made up of transverse ridges called…
Folia
The brain has white matter on the (OUTSIDE/INSIDE) and gray matter on the (OUTSIDE/INSIDE), while the spinal cord has white matter on the (OUTSIDE/INSIDE) and gray matter on the (OUTSIDE/INSIDE).
Inside
Outside
Outside
Inside
Posterior and Anterior Rootlets go on to make what?
Posterior and Anterior Roots, which go on to make Spinal Nerves
Posterior Rootlets enter the Spinal Cord via what?
Posterolateral Sulcus
Anterior Rootlets leave the Spinal Cord via what?
Anterolateral Sulcus
***This sulcus is poorly defined and hard to see
This is the region of gray matter that caps the posterior horn.
Substantia Gelatinosa
T/F. The body of the posterior horn contains interneurons and projection neurons that transmit somatic and visceral motor information.
False. Transmits somatic and visceral SENSORY information.
This is white matter located between the Substantia Gelatinosa (posterior horn) and the surface of the Spinal Cord.
Lissauer’s Tract
This nucleus has its cells located on the medial surface of the base of the posterior horn (T1 to L2). It has a prominent role in sensory processing and typically treated as part of posterior horn.
Clark’s Nucleus (Posterior Thoracic Nucleus)
The (POSTERIOR/ANTERIOR) horn contains cell bodies of lower motor neurons supplying skeletal muscle. The cells provide CNS control over body movements (voluntary or involuntary). Influenced by different pathways to modulate movements.
Anterior
This lies between the anterior and posterior horn and contains a collection of various projection neurons, sensory interneurons, and interneurons.
Intermediate Gray Matter
Preganglionic Sympathetic neurons (T1-L3), in the intermediolateral cell column, form the ________ _______. The axons leave via the ventral roots.
Lateral Horn
The _______ _______ nucleus spans S2-S4, but does not form a distinct lateral horn.
Sacral Parasympathetic
This lamina layer is a thin layer of gray matter covering the Substantia Gelatinosa.
Lamina I (Marginal Zone)
This lamina layer is the Substantia Gelatinosa.
Lamina II
These lamina layers are the body of the posterior horn.
Lamina III through VI
This lamina layer comprises some of the interneuron zones of the anterior horn.
Lamina VIII
This lamina layer consists of the clusters of motor neurons embedded in the anterior horn.
Lamina IX
This lamina layer is the zone of gray matter surrounding the central canal.
Lamina X
Primary afferents and lower motor neurons convey info to/from the CNS. Primary afferents terminate in the CNS on ________ neurons and are ipsilateral (with few exceptions).
Second-order
This type of neuron relays a signal from primary afferents (in the periphery) to a large in the CNS. Can cross the midline of the body.
Second-order neurons
This type of neuron relays the message to a final large in the a specific cortical area(s). Then the cortex decides on the given output.
Third-order neurons
Axons having similar connections bundles together, forming various tracts of the Spinal Cord. Many are named according to location of their cell body of origin and final destination. Naming indicates three important facts, which are…
1) If they are ascending or descending (i.e., corticospinal vs. spinocerebellar)
2) Location of the cell body of origin (i.e., cortex vs. spinal cord)
3) Location where the axons will terminate (i.e., spinal cord vs. cerebellum)
This type of ascending tract conveys ipsilateral proprioceptive, tactile, and vibratory information from the body (not face).
Posterior columns
This type of ascending tract relays information to the cerebellum, thalamus, and motor cortex to influence efficiency of motor activity.
Spinocerebellar tracts
This type of ascending tract relays pain, temperature, and nondiscriminative touch from the body (not face).
Anterolateral system (ALS)
This type of descending tract controls voluntary, fine movements of the musculature.
Corticospinal tract
This type of descending tract influences motor neurons innervating primarily axial and neck musculature.
Vestibulospinal tract
This type of descending tract excites flexor motor neurons and inhibits extensor motor neurons.
Rubrospinal fibers
