Neuroanatomy Exam 1

Dynamic systems theory

any system including the human nervous system can be studied at various levels of analysis

Microscopic

molecules and cells in the nervous system

Mesoscopic

groups of cells linked together in various systems

Macroscopic

the whole human interacting in their environment

Distributed control

at any one time the nervous system coordinates many different activities

Adaptation

the human nervous system is able to change which can lead to changes in behavior and can be shaped by the environment

Neuro-occupation

reciprocal relationship between the nervous system and occupation

Localization of function

particular structure in the nervous system can be loosely tied to particular functions

Topographical organization

the brain can loosely be compared to a map

Brodmann’s areas

classification system which uses numbers to label individual areas of the cortex that are cellularly similar

Hemispheric specialization

each hemisphere of the brain is connected to some specific functions

Phylogenetic layers

most newer parts of our brain are located at the top of our head and more primitive parts are located deeper and lower

Crossed representation

for most sensory and motor functions, the left side of the brain functionally corresponds to the right side of the body and vice versa

Cell

Cell body

Nerve fibers

Dendrites and axons

White matter

white tissue of the CNS rich with myelinated axons

Gray matter

gray tissue of the CNS rich with neuronal cell bodies (nuclei)

Glial cells, neuroglia, glia

non-neural cells

Sulcus (sulci)

crevices of the brain (2/3s) of the brain is found in the sulci)

Gyrus (gyri)

ridges of the brain

Fissure

a deep sulcus

Cortex

outer layer of an organ or body structure

Group(s) of functionally or structurally related cell bodies (CNS)

nucleus (nuclei)

Groups(s) of functionally or structurally related cell bodies (PNS)

ganglion (ganglia)

Group(s) of parallel axons (CNS)

tract, fasciculus, lemniscus, peduncle

Group(s) of parallel axons (PNS)

nerve, ramus, root

Group(s) of several parallel tracts or fasciculi

funiculus, column

Group of axons connecting one side of the CNS with the other

commisure

Group(s) of functionally related cells that from a layer

layer, lamina, stratum

CNS

brain and spinal cord which are enclosed by bone

PNS

extension of the CNS that includes 12 pairs of cranial nerves and 31 pairs of spinal nerves which aren’t encased by bone or protected by the blood-brain barrier

Autonomic nervous system (ANS)

innervates smooth muscle and glands; regulates homeostasis

Somatic nervous system (SNS)

innervates mainly musculoskeletal tissue and skin

What is in the diencephalon?

cerebellum and brainstem (midbrain, pons, and medulla)

What cells form the PNS?

Neural crest cells

Sulcus limitans

longitudinal groove in wall of the neural tube in the 4th week

What is dorsal to the sulcus limitans?

the alar plate

What function does the alar plate have?

sensory functions

What is ventral to the sulcus limitans?

the basal plate

What function does the basal plate have?

motor functions

What are the 3 primary vesicles?

prosencephalon, mesencephalon, and rhombencephalon

What are the 5 secondary vesicles?

telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon

Cervical flexure

between future brainstem and spinal cord; straightens later in development

Cephalic flexure

between future midbrain and diencephalon; persists in adulthood and is the reason for “the bend” in the neural axis

Pontine flexure

between future pons and medulla; does not persist but affects caudal brainstem

Teratogens

drugs or other agents that cause atypical development

Craniorachischisis

complete failure of neural tube to close; incompatible with life

Spina bifida occulta

atypical formatin of vertebral column only

Meningocele

herniation of meninges only

Myelomeningocele

herniation of spinal cord and meninges

Anencephaly

failure of rostral end of tube to close resulting in absent cerebral hemispheres; incompatible with life

Holoprosencephaly

partial or complete failure of prosencephalon to separate into diencephalon and telencephalon; usually fatal

Nature

general layout of the nervous system

Nurture

various connections are adjusted to meet demands of environment; also known as neuroplasticity

Critical periods

early development

Ongoing adjustments

learning and memory; constraint-induced movement therapy; etc

Neuroplasticity

the ability of the brain to change its own structure and function through activity and thought

Neurogenesis

creating new neurons

Neural stem cells

cells that can produce new CNS neurons or glial cells

Re-wiring

creating new neuronal pathways

Unmasking

uncovering existing, but rarely used neuronal pathways

Cortical re-organization

reassigning cortical “real estate”

Changes in synaptic efficiency

basis if learning and memory

Potentiation

an increase in synaptic efficiencyD

Depression

a decrease in synaptic efficiency

Short-term potentiation or depression

lasts a few minutes

Long-term potentiation or depression

produces lasting changes (hours to years); basis of learning and memory and what we hope to affect in neurorehab

Neuronal competetition

neurons compete for neurotropic factors during development

What are the 2 types of long-term memory?

declarative memory and nondeclarative memory

Declarative (explicit) memory

memory of facts, events, concepts, places

Nondeclarative (implicit) memory

also know as procedural memory; how-to memory

What are the 3 stages of declarative memory?

immediate memory, working memory, and long term memory

Retrograde amnesia

loss of memories from a period prior to the brain injury

Anterograde amnesia

deficit in forming new memories

What are the 3 general types of nondeclarative memory?

skills and habits, emotional associations, and conditioned reflexes

What are the 3 stages involved in motor learning?

cognitive, associative, and autonomous

Cognitive stage of motor learning

verbally guide motor task; requires much attention

Associative stage of motor learning

movement is refined and made more efficient

Autonomous stage of motor learning

movements are practically automatic; requires very little conscious attention

What areas of the brain are most affected in a TBI?

anteromedial temporal lobes and basal orbitofrontal cortex

How is memory affected with Karsakoff’s psychosis?

affects mammillary bodies and is characterized by anterograde amnesia and may lead to confabulation

Confabulation

filling in memory gaps by fabrication

What memory structures does Alzheimer’s affect?

bilateral hippocampus, temporal, and basal forebrain structures

Psychogenic amnesia

memory loss of an emotional event or autobiographical information due to dissociation and repression

What are the meninges comprised of?

collagen fibrils and fibroblasts

What are the 3 meninges?

dura mater, arachnoid mater, and pia mater

What are the 2 layers of the dura mater?

periosteal layer and meningeal layer

Falx cerebri

vertically oriented separating cerebral hemispheres

Subarachnoid space

between arachnoid and pial membranes and filled with csf

Arachnoid trabeculae

connective tissue arising from arachnoid and connect the arachnoid to the pia

Subarachnoid cisterns

enlargements in the subarachnoid space

What is the largest cistern?

cisterna magna

Arachnoid granulations (large) or villi (small)

small tufts of arachnoidal tissue project into dural sinuses

What are the 5 types of intracranial hemorrhage?

epidural hematoma, subdural hematoma, subarachnoid hemorrhage, intracerebral hemorrhage, and intraventricular hemorrhage

Spinal dura

single-layered (unlike dura mater)

Spinal epidural space

is an actual space which is used clinically for epidural anesthesia

Lumbar cistern

widest area of subarachnoid space in the spinal cord

Meningitis

inflammation of the meninges from pressure in the lungs

Meningocele

protrusion of the meninges outside of the vertebral canal

What are the 5 basic components of the lateral ventricles?

anterior horn, body, posterior horn, inferior horn, and atrium