 Automatic motor response to stimuli  Produces the same response every time  Reflex Arc  Step One: Arrival of stimulus and activation of receptor

 Step 2: Activate the sensory neuron  Step 3: Information processing by interneuron  Step 4: Activate motor neuron  Step 5: Response by effector (muscle or gland)

 Stretch Reflex  Automatic regulation of skeletal muscle  Allows for posture and balance  Doctors use to test condition of spinal cord  Ex: Knee Jerk Reflex

 Withdrawal Reflex  Move body away from stimulus  Strong when stimulus is pain  Ex: Flexor Reflex  Involves a limb  Ex: Grabbing a hot pan

 Babinski Sign  Stroke side of sole of foot—results in curled toes  Used to test CNS

 Sensation—information gathered by a receptor  Can filter out  Ex: Feel our clothes?  Posterior column pathway  Sends fine touch, pressure, vibration and position sensations  Sends to primary sensory cortex in cerebrum