Exam 2 - CNS Flashcards
Primary Motor Cortex
Precentral gyrus Voluntary muscle control (skeletal) More surface area to fine movements (ie face) SIMPLE MOVEMENTS Frontal Lobe
Prefrontal
Thinking ahead
Taking initiative
Primary Somatosensory Cortex
Postcentral gyrus
General sensation (pain, temp, touch)
Concious awareness of general somatic senses
Parietal lobe
More SA to more sensitive areas (ie face)
Premotor Cortex
In front of precentral gyrus
Planning movements
Complex movements –> has to be learned and practiced
Special Cortices in Temporal Lobe
Olfactor cortex
Auditory cortex and association area
Special Sensory Cortex in Occipital Lobe
Visual cortex
Pyramidal cells
large neurons of primary motor cortex
Cerebral White Matter (axon fibers) - types
- Commissural fibers
- Association fibers
- Projection fibers
Commissure tract&functions
composed of commissural fibers
allows communication between cerebral hemispheres
largest commissure = corpus callosum
Association fibers
connect different parts of same hemisphere
Projeciton fibers
connect different parts
i.e. cortex –> pons/cerebellum
Basal Ganglia (4)
subcortical grey matter
group of nuclei deep within cerebral white matter
1. caudate nucleus (Huntington’s)
2. Putamen (Huntington’s)
3. Globus pallidus
4. Amygdaloid body (LIMBIC SYSTEM) (FEAR)
**cooperate with cerebral cortex in performing movements
Caudate nucleus&lentiform nucleus
Huntington’s disease
arches over thalamus
“lens shaped”
=corpus striatum
Cranial Meninges
Dura mater
Arachnoid mater
Pia mater
Limbic System (function and 5 parts)
emotion and behavior
- cingulate gyrus
- dentate gyrus
- parahippocampal gyrus
- hippocampus
- fornix (axon fibers - connects parts of limbic system)
Dura mater (3 parts)
- Falx cerebri
- Tentorium cereblli
- Falx cerebell
Choroid plexus
filters cerebral spinal fluid (wastes go into capillaries, nutrients go into csf)
Thalamus
sensory relay center between brain stem and cortex
Proencephalon
Telecephalon –> cerebrum (cerebral hemispheres and cortex)
Diencephalon (thalamus and hypothalamus)
Forebrain
Mesencephalon
Tectum (superior and inferior colliculi, corpora quadrigemina)(superior to aqueduct) and tegmentum (cerebral peduncles, substanstia nigra) (inferior to aqueduct)
Midbrain
Rhombencephalon
Metencephalon –> cerebellum and pons
Myelencephalon –> medulla oblongata
Hindbrain
medial geniculate nucleus
specific thalamic nuclei
auditory relay nucleus
lateral geniculate nucleus
specific thalamic nuclei
visual relay nucleus
Functions of the Hypothalmus
visceral control center of the brain
- hormones via the pituitary
- autonomic nervous system
- feeding and drinking
- sexual activity
- temperature
- sleep-wake cycles
- memory
Superior colliculi
visual center
Inferior colliculi
auditory center
cerebral peduncles
part of tegmentum
group of projections (tract of axon fibers)
connect midbrain with cerbrum
Red nucleus
maintenance of muscle tone and limb position
Substantia nigra
part of tegmentum
Parkinson’s disease
crus cerebri
corticospinal tract
Pons
Contains nuclei of CN V, VI, VII
4th ventricle
Middle cerebellar peduncle (connects pons with cerebellum)
Inferior cerebellar peduncle
Cerebellum (functions)
- Balance (maintains posture, equilibrium, coordinates and smoothes movements)
- Cognition (language, problem solving, planning tasks)
Cerebellar Lesions
- Intentional tremor
2. Imbalance and “drunken” gait (like a duck)
Medulla Oblongata (5)
- Pyramid
- Olivary nuclei
- Reflex centers
- Cardiovascular centers
- Respiratory rhymicity center
Pyramid
Medulla oblongata Corticospinal tract (fibers make cross) Inferior olive pyramid
Olivary nuclei
Control cardiovascular and pulmonary systems
Medulla oblongata
Spinal cord damage between C5-S4
Paraplegia
Spinal cord damage at brachial plexus origin
Quadriplegia
Damage at or above phrenic nerve origin
asphyxiation and death (diaphragm control)
Ascending tracts of white matter
sensory
Descending tracts of white matter
motor
Lesion of corticospinal tract
Loss of voluntary motor control
AND spastic paralysis (spinal reflexes can still be evoked)
Lower motor neurons (fibers and lesion)
GSE fibers (final common pathway to skeletal muscle) Lesion deprives skeletal muscle of motor control --> flaccid paralysis (loss of reflexes and muscle atrophy)
