Neuroanatomy 1 Flashcards
Terms of relationship and comparisson:
What are they in the CNS and why are they different in the CNS than in the rest of the body?
They are varied in the CNS because in development, the long axis of the CNS is bent
Therefore, intsead of A/P, A/I which refer to the long axis that is straight, we use:
Rostral - towards the nose
Caudal - towards the tail
Dorsal - nearer to the TOP
Ventral - nearer to the BOTTOM
Medial - nearer to the median plane
Lateral - nearer to the lateral plane
Telencephalon: overall structure description
Aka Cerebrum
Consists of 2 large hemispheres separated from each other by a deep, longitudinal cerebral fissure.
Telencephalon: what structures make up the telencephalon?
Cerebral Cortex Subcortical White Matter Basal Ganglia (nuclei) Hippocampus Amygdaloid (nucleus)
Telencephalon: Cerebral Cortex
Where is it?
It is the outer surface of the brain.
Telencephalon: Cerebral Cortex
How is it organized?
It is composed of 6 horizontal layers of neuron cell bodies that are further organized in a vertical arrangement, forming columns. These areas are subdivided based on cytoarchitectural features (meaning differences in the neurons they are made up of) and are called Brodmann’s Areas. These areas are structurally different, and it therefore follow that they are functionally different.
Telencephalon: Cerebral Cortex
What characterizes its physical appearance?
Characterized by gyri or crests of cortical tissue, andy by sulci, which are grooves that divide the gyri from one another.
Though it appears symmetrical externally, it is not completely symmetrical in structure, and it is not symmetrically equivalent in function.
Telencephalon: Cerebral Cortex
Major Sulci - What are they, how do they divide the cortex?
The major sulci divide the cortex into 4 lobes.
They are imaginary lines connecting certain sulci, and connecting certain sulci with the preoccipital notch to help demarcate the lobes.
Telencephalon: Cerebral Cortex
Major sulci - name the 5 major sulci and state which view they can be seen in
Central aka Rolandic - lateral Lateral aka Sylvia - lateral Parieto-occipital - lateral and medial Cingulate - medial Collateral - medial
Telencephalon: Cerebral Cortex
How are the lobes named?
Lobes are named for the overlying cranial bones.
Frontal Lobe: General Functional Areas
Primary somatomotor cortex
Nomenclature
Location
Function
Aka primary motor cortex, M1, Brodmann’s area 4
Location: Precentral gyrus, anterior paracentral gyrus
Function: executing movement
**Motor Homunculus applies here. We have more fine motor control in the areas that are depicted larger and therefore more cortex is devoted to those areas.
Frontal Lobe: General Functional Areas
Premotor Areas
Areas it includes
Nomenclature
Location
Function
Includes:
1) premotor and supplementary motor areas
2) frontal eye fields
Other names:
1) M2, Brodmann’s area 6
2) Brodmann’ area 8
Location: Rostral to the precentral gyrus and the anterior paracentral gyrus; rostral to primaty somatomotor
Function: Planning movement
Frontal Lobe: General Functional Areas
Broca’s Area
Nomenclature
Location
Function
Nomenclature:
Brodmann’s areas 44 and 45
Location:
Usually in the left hemisphere
inferior frontal gyrus - pars opercularis and pars triangularis
Function:
Production of language
Frontal Lobe: General Functional Areas
Prefrontal Cortex
Nomenclature
Divisions
Location
Function
Nomenclature:
Frontal association cortex
**Anterior multimodal association cortex
Brodmann’s areas 9-12 and 45-47
Divisions:
Lateral
Medial
Orbitofrontal
Location:
Rostral to the promotor areas
Makes up most of the rostral cortex
Function:
Intention: Sensory integration and selection of appropriate motor responses
cognition
receives all the information from the posterior multimodal area
Parietal Lobe: General Functional Areas
Primary Somatosensory Cortex
Nomenclature
Location
Function
Nomenclature:
aka Primary Sensory Cortex
S1
Brodmann’s areas 1,2,3
Location:
Postcentral gyrus, posterior paracentral gyrus
Function:
Somatosensory perception
**Sensory Homunculus - the areas where we have to most receptors are depicted the largest because those areas have a larger amount of cortex dedicated to them.
Parietal Lobe: General Functional Areas
Secondary Somatosensory Cortex
Nomenclature
Location
Function
Nomenclature:
aka S2
Location:
Superior bank of the lateral fissure
Function:
Unimodal - an associational area where sensory input is INTERPRETED (somatosensory interpretation)
Parietal Lobe: General Functional Areas
Wernicke’s Area
Nomenclature
Location
Function
Nomenclature:
aka Brodmann’s areas 39 and 40
Location:
Usually in the Left Hemisphere
Supramarginal gyrus, angular gyrus (at the end of the lateral fissure)
Function:
COMPREHENSION of language
Parietal Lobe: General Functional Areas
Posterior Parietal Cortex
Nomenclature
Location
Function
Nomenclature:
Aka Brodmann’s areas 5 and 7
Location:
Superior Parietal Lobule
Function;
Somatosensory interpretation AND integration (submodalities, vision) - right next to the multimodal association cortex so it shares its function
Plays a role in spatial vision - showing selectivity for direction and speed of movement rather than size, shape, etc.
Parietal Lobe: General Functional Areas
Parietal-Temporal-Occipital Association Cortex
Nomenclature
Location
Function
Nomenclature:
aka Posterior multimodal association cortex
Brodmann’s areas 37, 39, 40
Location:
Junction of the parietal, temporal, and occipital lobes
Function:
Somatic, visual, and auditory sensation integration.
Mediates attention and recognition
Temporal Lobe: General Functional Areas
Primary Auditory Cortex
Nomenclature
Location
Function
Nomenclature:
Aka A1
Brodmann’s area 41
Location:
Transverse temporal gyri
Function:
Auditory perception
Temporal Lobe: General Functional Areas
Secondary Auditory Cortex
Nomenclature
Location
Function
Nomenclature:
aka A2
Auditory Association Cortex
Brodmann’s area 22
Location:
Superior temporal gyrus
Function:
Auditory interpretation
Temporal Lobe: General Functional Areas
Wernicke’s area
Nomenclature
Location
Function
Nomenclature:
aka Brodmann’s area 22
Location:
Straddles the parietal and temporal regions
Usually located in the Left hemisphere
Superior temporal gyrus (temporal lobe)
Function:
Comprehension of language
Occipital Lobe: General Functional Areas
Primary Visual Cortex
Nomenclature
Location
Function
Nomenclature:
aka V1
Striate Cortex
Brodmann’s area 17
Location:
Cuneus
Lingual Gyrus
Function:
Visual Perception
Occipital Lobe: General Functional Areas
Secondary Visual Cortex
Nomenclature
Location
Function
Nomenclature: aka V2 - V5 Extrastriate cortex Visual association cortex Brodmann's areas 18-21, 37
Location:
Very large
Occipital Gyri
Includes middle and medial superior temporal area (located in the occipital and parietal lobes) and inferior temporal cortex)
Function:
Visual interpretation
General Functional Areas: Frontal Lobe
What general functional areas are in the frontal lobe?
Primary Somatomotor Cortex
Premotor Cortex
Broca’s Area
Pre-frontal Cortex
General Functional Areas: Parietal Lobe
What general functional areas are in the parietal lobe?
Primary Somatosensory Cortex Secondary Somatosensory Cortex Wernicke's Area Posterior Parietal Cortex Parietal-Temporal-Occipial Cortex
General Functional Areas: Temporal Lobe
What general functional areas are in the temporal lobe?
Primary Auditory Cortex
Secondary Auditory Cortex
Wernicke’s Area
Parietal-Temporal-Occipial Cortex
General Functional Areas: Occipital Lobe
What general functional areas are in the occipital lobe?
Primary Visual Cortex
Secondary Visual Cortex
Parietal-Temporal-Occipial Cortex
Regions: Insula
Location?
Deep Inside the Lateral Fissure
Regions: Insula
What General Functional Area is in the Insula?
Name
Brodmann’s Area
Other structures involved
Function
Primary Taste Cortex
Brodmann’s Area 43
Primary Taste area also includes the inferior frontal gyrus pars opercularis and the parietal postcentral gyrus
Function: Taste Perception
Regions: Limbic
Location?
Medial Rim of the hemisphere, specifically in the temporal lobe.
Regions: Limbic
What are the structures in this region?
Cingulate Gyrus, Parahippocampal gyrus, uncus, parahippocampal sulcus, callosal sulcus
Regions: Limbic
What are the General Functional Areas in this region?
Part of the Limbic System, Primary Olfactory Cortex
Regions: Limbic - General Functional Areas
Limbic System
Brodmann’s area
Other associated areas
Function
Brodmann’s 28 - 36, 38
Includes hippocampus, amygdaloid, and parts of the basal ganglia, hypothalamus, prefrontal cortex.
Function: Important in emotional states, drive related behavior, and memory formation
Regions: Limbic - General Functional Areas
Olfactory Cortex
Brodmann’s area
Limbic region structures
Other associated areas
Function
Brodmann’s: 28, 34 - 36, 38
Limbic structures: parahippocampal gyrus, uncus
Also includes, frontal olfactory tubercle and amygdaloid.
Function: Smell perception
Subcortical White Matter
What is its function?
Creates communications between parts of the brain.
Subcortical White Matter
Where is it located?
Internal to the Cortex
Subcortical White Matter
What is it made up of?
Myelinated axons and oligodendrocytes
Subcortical White Matter
What are the three types of fibers in the subcortical white matter?
Association, commissural, projection
Subcortical White Matter - Commisural Fibers
Relevant Structures
Function
Relevant Structures:
Corpus Callosum - connects the hemispheres
Function: Interconnects corresponding structures on either side of the neuraxis (communication between hemispheres)
Subcortical White Matter - Projection Fibers
Relevant Structures
Function
Relevant Structures:
Internal Capsule - between thalamus and basal ganglia
Function:
1) Carry (corticopetal) axons that originate outside the telencephalon and project to the cerebral cortex
2) Carry (corticofugal) axons that arise from the cerebral cortex and project outside the telencephalon
Basal Ganglia
Location? Composition?
Between the temporal cortex and the lateral ventricle on both sides of the internal capsule.
Composed of neuron cell bodies.
Basal Ganglia
What structures from the telencephalon does it include? What other regions contain basal ganglia strucures?
Structures in the telencephalon:
Striatum: Caudate, putamen
Globus pallidus (internal segment and external segment)
Includes structures of the diencephalon and midbrain.
Basal Ganglia: Function
1) Gate proper initiation of movement
2) Contribute to emotional states
3) Certain forms of cognition (like learning new skills)
Hippocampus: Location
Internal to the parahippocampal gyrus of the limbic region
Hippocampus: Composition
Composed of horizontal layers of neuron cell bodies
Hippocampus: Relevant structures
Hippocampus proper
Hippocampus: Function
Memory Formation
Amygdaloid (Nucleus): Location
Internal to the uncus of the limbic region, just rostral to the hippocampus
Amygdaloid (Nucleus): Composition
Composed of an aggregation of neuron cell bodies
Amygdaloid (Nucleus): Function
Important to emotional states and drive-related behavior
Diencephalon: Location
Situated between the telencephalon and the brain stem
Diencephalon: What cavity is associated with the diencephalon? How is it organized with reference to the cavity?
Cavity: The 3rd ventricle
The right and left halves contain symmetrically distributed cell groups separated by the space of the third ventricle
Diencephalon: What structures does it include?
dorsal thalamus (aka thalamus), hypothalamus, ventral thalamus (aka subthalamus), and epithalamus
Diencephalon: Dorsal Thalamus
Location and Structural characteristics
This is what we refer to as the thalamus.
It is located superior to the hypothalamic sulcus, between the interventricular foramen and the splenium of the corpus callosum.
It is the largest subdivision of the diencephalon.
It is an ovoid mass containing about 50 nuclei
Diencephalon: Dorsal Thalamus
How are the nuclei in this region characterized?
Contains relay and association nuclei
Diencephalon: Dorsal Thalamus
Relay Nuclei
Recieve input predominantly from one source
Diencephalon: Dorsal Thalamus
Association Nuclei
Recieve input from a number of different structures and usually send output to more than one association area.
Diencephalon: Dorsal Thalamus
Relevant external structures
Lateral geniculate body, medial geniculate body, pulvinar
Diencephalon: Dorsal Thalamus
What kinds of structures does it contain internally?
Sensory, Motor, Modulatory
Diencephalon: Dorsal Thalamus
Function
Process most of the information that reaches the cerebral cortex.
Hypothalamus: Location
Inferior to the hypothalamic sulcus, superior to the pituitary gland (with which it has a close relationship) and caudal to the lamina terminalis.
Hypothalamus: Composition
Composed of Aggregates of neuron cell bodies and axons.
Hypothalamus: Relevant External Structures
Infundibulum - this is the pituitary stalk where the hypothalamus communicates with the pituitary gland
Mammillary bodies
Hypothalamus: Relevant Internal Structures
Suprachiasmatic nucleus
Hypothalamus: Function
1) Integrates autonomic response and endocrine function with behavior.
2) Controls homeostasis, reproduction, and emergency response to stress
Ventral Thalamus: Location, Composition
Aka subthalamus
Caudal to the hypothalamus, rostral to the diencephalon-brainstem junction and lateral to the midline.
Composed of aggregations of neuron Cell Bodies
Ventral Thalamus: Function
Related to the basal ganglia of the telencephalon
Epithalamus: Location, Composition
In very close approximation tot he posterior commisure
Composed of aggregates of cell bodies
Epithalamus: Relevant Structure
Pineal gland (external
Epithalamus: Function
Epithalamus is related to the limbic system
The pineal gland plays a role in circadian rhythm.
Subcortical White Matter - Association Fibers
Relevant Structures
Function
Relevant Structures:
Fasiculi
Function: Interconnect various areas of cortex within the same hemisphere
