The Central The Central Nervous SystemNervous System

CNSCNS

Meninges of the BrainMeninges of the Brain Dura Mater (HARD MOTHER) Dura Mater (HARD MOTHER)

- outer layer, strong white - outer layer, strong white fibrous tissue.fibrous tissue.

Arachnoid membrane Arachnoid membrane (SPIDER WEB) - middle layer, (SPIDER WEB) - middle layer, cobweb like layer.cobweb like layer.

Pia Mater (SOFT MOTHER)-Pia Mater (SOFT MOTHER)-inner layer, adheres to the inner layer, adheres to the brain, translucent. brain, translucent.

Divisions of MeningesDivisions of Meninges

Falx cerebri- parts right Falx cerebri- parts right and left cerebral and left cerebral hemisphereshemispheres

Sinuses within the dura Sinuses within the dura function as venus function as venus reservoirsreservoirs

Pia mater contains blood Pia mater contains blood vessels that surround vessels that surround brainbrain

Falx cerebri

Falx cerebri

Did you know?Did you know?

Menigitis- inflammation of the Menigitis- inflammation of the meniges caused by bacteria, viral or meniges caused by bacteria, viral or fungal infections. fungal infections.

Subdural Hematoma- large blood clot Subdural Hematoma- large blood clot found in under the dura mater. found in under the dura mater. Usually sign of trauma.Usually sign of trauma.

Cerebral Spinal fluidCerebral Spinal fluid

CSF- provides a cushion of protection around brain spinal cord.CSF- provides a cushion of protection around brain spinal cord. Ventricles- 4 fluid filled spaces in the brain.Ventricles- 4 fluid filled spaces in the brain. 11stst & 2 & 2ndnd (2 lateral), 3 (2 lateral), 3rdrd and 4 and 4thth (very tiny) (very tiny)

CSF is formed in the choroid plexuses then circulated via the CSF is formed in the choroid plexuses then circulated via the ventriclesventricles

Ventricles in the BrainVentricles in the Brain

The Brain StemThe Brain StemBrain Stem(vital centers)Brain Stem(vital centers)

Medulla Oblongata- controls heart rate, blood pressure, breathing

Landmarks- olives & pyramids

Pons- helps control vital functions

The MidBrainThe MidBrainMidbrain- connects brain Midbrain- connects brain

stem and cerebrum via stem and cerebrum via the cerebral pedunclesthe cerebral peduncles

Corpora quadrigemina (“body Corpora quadrigemina (“body of four twins”) is the of four twins”) is the inferior and superior inferior and superior colliculi.colliculi.

Inferior colliculi functions as Inferior colliculi functions as auditory processing auditory processing center.center.

Superior colliculi function as Superior colliculi function as visual processing center.visual processing center.

Red nucleus and substantia Red nucleus and substantia nigri(black matter) nigri(black matter) function in motor control., function in motor control., secretes dopamine.secretes dopamine.

The BrainThe BrainCerebellumCerebellum

Controls skilled muscle Controls skilled muscle movements, posture and movements, posture and balance.balance.

Is connected to thalamus Is connected to thalamus and motor cortex areas of and motor cortex areas of the cerebrum.the cerebrum.

Diencephalon “between-Diencephalon “between-brain”brain”

HypothalamusHypothalamus Connects info from nervous and endocrine to maintain Connects info from nervous and endocrine to maintain

homeostatsis.homeostatsis. Regulates appetite and feelings of satisfaction. Regulates appetite and feelings of satisfaction. Mind-body link (psychosomatic affect).Mind-body link (psychosomatic affect). Temperature control siteTemperature control site

DiencephalonDiencephalon

ThalamusThalamus detects mild pain and temperature sensationdetects mild pain and temperature sensation determines whether something is pleasantdetermines whether something is pleasant Relays sensory info to cerebrumRelays sensory info to cerebrum

Optic chiasma-Optic chiasma- where optic nerve cross before entering the where optic nerve cross before entering the brainbrain

Pineal gland-Pineal gland- secretes melatonin to regulate sleep.secretes melatonin to regulate sleep.

The CerebrumThe CerebrumGyrus (bulge) Sulcus (crevice)

The CerebrumThe Cerebrum

The CerebrumThe Cerebrum

CerebrumCerebrum Cerebral cortex- Cerebral cortex-

gray matter on the gray matter on the outside of the outside of the cerebrumcerebrum Responsible for Responsible for

conscious thoughtconscious thought MemoryMemory AwarenessAwareness languagelanguage reasoning.reasoning.

Cerebral plasticity- regions can vary in their functions between different individuals.

Regions of the CerebrumRegions of the Cerebrum

Corpus Callosum-Corpus Callosum-connects the right connects the right and left hemispheresand left hemispheres

Limbic system- Limbic system- controls emotions, controls emotions, anger, sorrow and anger, sorrow and pleasure.pleasure. Hippocampus- found

in the limbic system and associated with short term memory

Amygdala- helps decode

Corpus callosum

Olfactory tract

Mammillary bodies

Fornix

Anterior thalamic nuclei

Amygdala

Hippocampus Parahippocampal gyrus

Cingulate gyrus Hypothalamic

nuceli

Regions of the CerebrumRegions of the Cerebrum

Reticular Activating system-Reticular Activating system-when stimulated causes when stimulated causes consciousnessconsciousness REM- rapid eye movement REM- rapid eye movement

sleep, dreamingsleep, dreaming SWS- slow wave sleep, no SWS- slow wave sleep, no

dreamingdreaming

Image of Brain Image of Brain Homunculus Homunculus

““little man” little man” represented in represented in each each hemisphere of hemisphere of the brain, the brain, depicts amount depicts amount of sensory of sensory receptors in receptors in certain areascertain areas

Disorders of the BrainDisorders of the BrainStroke (Cerebrovascular accident CVA)Stroke (Cerebrovascular accident CVA)

Usually because of a clot there is a cessation of blood to the Usually because of a clot there is a cessation of blood to the brain and the region is starved of oxygen.brain and the region is starved of oxygen.

Hemiplegia- paralysis on one side of the body.Hemiplegia- paralysis on one side of the body.

Huntington diseaseHuntington disease Involuntary movements, dementia and deathInvoluntary movements, dementia and death

Creutzfeldt-JakobCreutzfeldt-Jakob Human mad cow disease. A prion causes protein Human mad cow disease. A prion causes protein

denaturization in the brain.denaturization in the brain.

SeizuresSeizures sudden burst of neuron activity. Epilepsy is chronic seizure, sudden burst of neuron activity. Epilepsy is chronic seizure,

normally idiopathic.normally idiopathic.

The Spinal CordThe Spinal Cord Located Located

within the within the spinal cavity spinal cavity along with the along with the meninges, meninges, cerebrospinal cerebrospinal fluid, adipose fluid, adipose tissue and tissue and blood vesselsblood vessels

The Spinal ColumnThe Spinal Column Dorsal nerve rootDorsal nerve root

Carry sensory information to Carry sensory information to the spinal cord, afferent the spinal cord, afferent pathwayspathways

Cell bodies of these unipolar Cell bodies of these unipolar neurons make up a small area neurons make up a small area of gray matter called the dorsal of gray matter called the dorsal root ganglionroot ganglion

Ventral nerve rootVentral nerve root Carries motor information out of Carries motor information out of

spinal cord, efferent pathwaysspinal cord, efferent pathways Cell bodies of these mulitpolar Cell bodies of these mulitpolar

neurons compose the inner core neurons compose the inner core of gray matterof gray matter

Spinal NerveSpinal Nerve Dorsal and Ventral join together Dorsal and Ventral join together

to form this single nerveto form this single nerve

The Spinal CordThe Spinal Cord

The Spinal CordThe Spinal Cord

Ascending Ascending TractsTracts Conduct Conduct

sensory sensory impulses up to impulses up to the brainthe brain

Descending Descending tractstracts Conduct motor Conduct motor

impulses down impulses down from the brainfrom the brain

Nerve RepairNerve Repair Nerve damage caused Nerve damage caused

by trauma can by trauma can sometime be repaired sometime be repaired by regrowth of the by regrowth of the axonaxon

Neurons can never Neurons can never replicate themselvesreplicate themselves

There is evidence that There is evidence that shows new neurons shows new neurons can grow out of adult can grow out of adult stem cells in the stem cells in the spinal cordspinal cord

CNS

PNS

Spinal Cord InjuriesSpinal Cord Injuries