Download 14-1

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Neuropsychopharmacology wikipedia, lookup

Feature detection (nervous system) wikipedia, lookup

Stimulus (physiology) wikipedia, lookup

Circumventricular organs wikipedia, lookup

Neuroanatomy wikipedia, lookup

Clinical neurochemistry wikipedia, lookup

Metastability in the brain wikipedia, lookup

Time perception wikipedia, lookup

Environmental enrichment wikipedia, lookup

Neuroplasticity wikipedia, lookup

Causes of transsexuality wikipedia, lookup

Holonomic brain theory wikipedia, lookup

Brain wikipedia, lookup

Neuroeconomics wikipedia, lookup

Cognitive neuroscience wikipedia, lookup

Connectome wikipedia, lookup

Neuropsychology wikipedia, lookup

Limbic system wikipedia, lookup

Neural correlates of consciousness wikipedia, lookup

Aging brain wikipedia, lookup

Neurophilosophy wikipedia, lookup

Human brain wikipedia, lookup

Brain Rules wikipedia, lookup

Brain morphometry wikipedia, lookup

Neuroesthetics wikipedia, lookup

History of neuroimaging wikipedia, lookup

Cognitive neuroscience of music wikipedia, lookup

Selfish brain theory wikipedia, lookup

Neurolinguistics wikipedia, lookup

Lateralization of brain function wikipedia, lookup

Neuroinformatics wikipedia, lookup

Dual consciousness wikipedia, lookup

Haemodynamic response wikipedia, lookup

Biochemistry of Alzheimer's disease wikipedia, lookup

Blood–brain barrier wikipedia, lookup

Subventricular zone wikipedia, lookup

Eyeblink conditioning wikipedia, lookup

Functional magnetic resonance imaging wikipedia, lookup

Intracranial pressure wikipedia, lookup

Cortical cooling wikipedia, lookup

Affective neuroscience wikipedia, lookup

Sports-related traumatic brain injury wikipedia, lookup

Emotional lateralization wikipedia, lookup

Transcript
The Brain and Cranial Nerves
• Largest organ in the body at almost 3 lb.
• Brain functions in sensations, memory, emotions, decision
making, behavior
14-1
Principal Parts of the Brain
• Cerebrum
• Diencephalon
– thalamus &
hypothalamus
• Cerebellum
• Brainstem
– medulla, pons &
midbrain
14-2
Protective Coverings of the Brain
• Bone, meninges & fluid
• Meninges same as around
the spinal cord
– dura mater
– arachnoid mater
– pia mater
14-3
Blood Supply to Brain
• Uses 20% of our bodies oxygen & glucose needs
– blood flow to an area increases with activity in that area
– deprivation of O2 for 4 min does permanent injury
• at that time, lysosome release enzymes
• Blood-brain barrier (BBB)
– protects cells from some toxins and pathogens
• proteins & antibiotics can not pass but alcohol & anesthetics do
– tight junctions seal together epithelial cells, continuous
basement membrane, astrocyte processes covering capillaries
14-4
Cerebrospinal Fluid (CSF)
• 80-150 ml (3-5oz)
• Clear liquid containing glucose, proteins, & ions
• Functions
– mechanical protection
• floats brain & softens impact with bony walls
– chemical protection
• optimal ionic concentrations for action potentials
– circulation
• nutrients and waste products to and from bloodstream
14-5
Origin of CSF
• Choroid plexus = capillaries covered by ependymal cells
– 2 lateral ventricles, one within each cerebral hemisphere
– 3rd ventricle
– 4th ventricle
14-6
Brain Stem
Medulla Oblongata
Pons
Midbrain
14-7
Ventral Surface of Medulla Oblongata
• Ventral surface bulge
– pyramids
– large motor tract
– decussation of most fibers
• left cortex controls right muscles
14-8
Reticular Formation
• Scattered nuclei in medulla, pons & midbrain
• Reticular activating system
– alerts cerebral cortex to sensory signals (sound of
alarm, flash light, or intruder) to awaken from
sleep
– maintains consciousness & helps keep you awake
with stimuli from ears, eyes, skin and muscles
• Motor function is involvement with
maintaining muscle tone
14-9
Cerebellum
• 2 cerebellar hemispheres
• Function
– correct voluntary muscle contraction and posture based on
sensory data from body about actual movements
– sense of equilibrium
14-10
Diencephalon Surrounds 3rd Ventricle
• Surrounds 3rd ventricle
• Superior part of walls is thalamus
• Inferior part of walls & floor is hypothalamus
14-11
Thalamus
• 1 inch long mass of gray mater in each half of brain
• Relay station for sensory information on way to cortex
• Crude perception of some sensations
14-12
Hypothalamus
• Mammillary bodies are relay station for olfactory reflexes;
infundibulum suspends the pituitary gland
• Major regulator of homeostasis
– receives somatic and visceral input, taste, smell & hearing
information; monitors osmotic pressure, temperature of blood
14-13
Functions of Hypothalamus
• Controls and integrates activities of the ANS which
regulates smooth, cardiac muscle and glands
• Synthesizes regulatory hormones that control the
anterior pituitary
• Contains cell bodies of axons that end in posterior
pituitary where they secrete hormones
• Regulates rage, aggression, pain, pleasure & arousal
• Feeding, thirst & satiety centers
• Controls body temperature
• Regulates daily patterns of sleep
14-14
Epithalamus
• Pineal gland
– endocrine gland the
size of small pea
– secretes melatonin
during darkness
– promotes sleepiness &
sets biological clock
• Habenular nuclei
– emotional responses to
odors
14-15
Cerebrum
(Cerebral Hemispheres)
• Cerebral cortex is gray matter
overlying white matter
– 2-4 mm thick containing billions
of cells
– grew so quickly formed folds
(gyri) and grooves (sulci or fissures)
• Longitudinal fissure separates left
& right cerebral hemispheres
• Each hemisphere is subdivided into 4 lobes
14-16
Limbic System
• Emotional brain--intense pleasure & intense pain
• Strong emotions increase efficiency of memory
14-17