PNS

somatic NS

voluntary control, neruons to the head trunk and limbs, sensory neurons carry info about external environment toward receptors.

12 pairs of cranial nerves, myelinated, but also connect to internal organs

32 pairs of spinal nerves, myelinated

each spinal never contains both sensory and motor neurons

autonomic NS

involuntary control

nerves stimulate or inhibit glands or cardiac or smooth muscle ‘maintains homeostasis by adjusting body conditions internally or externally, without being conscious of it

hypothalamus and medulla oblongata control it, has neurons bundled together with somatic system in cranial and spinal nerves

Sensory/Afferent Neurons

These neurons are activated by stimuli from the environment (like touching a hot surface) and send signals towards the brain and spinal cord.

Motor/Efferent Neurons:

These neurons carry messages from the brain and spinal cord to the muscles and glands, controlling movement and other actions.

Interneurons:

Found within the brain and spinal cord, connect sensory and motor neurons, relaying and processing the signals before a response is sent out.

hind brain

coordination and homeostasis

midbrain

processing sensory input

forebrain

thought, learning, emotion

occipital lobe

lobe of cerebral cortex that receives and analyzes visual information needed for visual recognition

temporal lobe

lobe of cerebral cortex that shares in the processing of visual information, main function is auditory reception

parietal lobe

receives and processes sensory information from skin, helps to process information about body position and orientation

• highest concentration of sensory receptors in face hands and genitals

frontal lobe

integrates information from other brain parts contains reasoning critical thinking memory and personality

• language use

• contain motor areas controlling various aspects of precise voluntary motor movement