CHAPTER 8.5: NERVOUS

SYSTEM

SPINAL CORD INJURIES General paralysis Severe damage to spinal cord Loss feeling from injury down Quadriplegia—lose control of both arms

and legs

SPINAL INJURIES CONT… Paraplegia Lose control of just the legs Repair Impossible naturally No cell division of neurons Trying artificial division Uses stem cells

THE BRAIN About 35 billion neurons About 3 pounds Cerebrospinal fluid (CSF) Brain floats in this Makes brain light Transports nutrients, neurotransmitters,

and wastes Lumbar puncture—useful in determining

CNS disease Replaced every 8 hours

THE CEREBRUM Largest part of the brain Conscious Thought Intelligence Gray matter—superficial layer White matter—deep layer Contains axons Gyri—grooves that increase the surface

area Left and Right Lobes Control opposite sides of the body

FIGURE 8.16A

CEREBRUM CONT… Parietal Lobe Primary motor cortex Directs voluntary movements Primary sensory cortex Receives somatic sensory information Ex: Touch, pressure, pain, temperature

FIGURE 8.16B

CEREBRUM CONT… Occipital Lobe Visual cortex All visual information

FIGURE 8.16B

CEREBRUM CONT… Frontal Lobe Gustatory cortex Taste sensations

FIGURE 8.16B

CEREBRUM CONT… Temporal Lobe Auditory cortex—hearing Olfactory cortex—smell

FIGURE 8.16B