Study Guide  3  Nervous System

Cerebral cortex -  conscious mine and motor control

Cerebral white matter – communication between cerebral cortex and lower CNS centers

Basal nuclei – regulating attention and cognition, inhibits unnecessary movements

Thalamus relays and edits signals

Hypothalamus – visceral control center of body, helps overall homeostasis

Epithalamus – contains  pineal glands

            Pineal gland produces melatonin which helps you sleep, regulated by signals from eye, regulates internal body clock

Brainstem – contains midbrain, pons, and medulla oblongata

Midbrain – reticular activating system ---- filters info, helps you be awake

Pons – communication between parts of brain

Medulla oblongata –respiratory centers, cardiovascular centers

Cerebellum – coordination of movements

Limbic system – seat of the emotions

Psychosomatic illness – stress stimulates parts of brain that cause symptoms of illness

Hippocampus- important in memory

Narcolepsy – falling suddenly to sleep

Insomnia – can’t fall asleep

Sleep apnea – stop breathing during sleep

Memory –

  short term memory   similar to ram on a computer, you store stuff here temporarily such as this material for this test

  long term memory – stored forever

                                    dependant on

                                               emotional state, rehearsal, association, automatic memory

cerebral palsy – caused by lack of oxygen, usually during delivery

anencephaly – baby has no brain

spina bifida – incomplete formation of vertebral column, usually caused by lack of folate in diet

pg 482 – mad cow disease

spinal reflexes – do not require brain participation, example – pulling hand from hot stove

Sensory adaptation – phenomenon of a sensation becoming less noticeable once it has been recognized by constant repeated stimulation.

Sensation occurs when nerve impulses arrive at the cerebral cortex

Perception occurs when the cerebral cortex interprets the meaning of sensation

Proprioceptors – receptors that allow us to know where our limbs are in space

Referred pain – pain that seems to be coming from one area but actually originates from another area due to shared nervous pathways

Taste buds have chemical receptors that bind to molecules that cause sensations of tastes.

Olfactory cells – modified neurons in nose that detect chemicals that are interpreted in the brain as smell

Olfactory fatigue – sensory adaptation to smell

Cataracts – the lens becomes opaque and blocks light transmission

Retinal detachment – retina comes loose from back of eye,  immediate emergency, can save vision if treated immediately, first sign may be blindness in top half of visual field

Photoreceptors

            Rods – black and white vision, night vision

            Cones – color vision

Color blindness – carried on sex chromosome, usually only males get it

 Nearsightness—eyeball is physically too long, only can focus on close objects

Farsightness – eyeball is physically too short, only can focus on far objects

Astigmatism  -- eyes focus on different planes

Depth perception is possible because both eyes focus on slightly different angles and the brain puts it all together

Hearing

 Sound wave vibrate tympanic membrane, it vibrates earbones, (malleus, incus, stapes) this vibrates inner ear, stimulates tiny hairlike nerve fibers which send signals to brain and are interpreted as sound

Balance – semicircular canals in ear are filled with fluid.  Tiny hairlike nerve endings sense change in position of head.

Nystagmus -  eye movement after rotation due to reflex set off by vestibular system

Motion sickness is caused by sensory imbalance