Vestibular sensation. When you move your head, the ____ ____ adjacent to the cochlea monitors movement and directs compensatory movements of your eyes.
The ____ ____ respond to pressure, bending, or other distortions of the receptor. They include touch, pain, and other body sensations, as well as vestibular sensation, which detects the position and movement of the head.
Sensations from the vestibular organ detect the direction of tilt and the amount of acceleration of the head. Vestibular sensations are critical for guiding eye-movement and ____ ____.
The vestibular organ, consists of the ____, ____, and three semicircular canals.
saccule : utricle
The vestibular receptors are modified ____ receptors.
Calcium carbonate particles called ____ lie next to hair cells, when the head tilts in different directions, the otoliths push against different sets of hair cells and excite them.
The three ____ ____, oriented in perpendicular planes, are filled with a jellylike substance and lined with hair cells.
Acceleration of the head at any angle causes the ____ ____ in one of these canals to push against the hair cells.
Action potentials initiated by cells of the vestibular system travel through part of the ____ ____ ____ to the brainstem and cerebellum. (The eighth cranial nerve contains both an auditory component and a vestibular component.)
eighth cranial nerve
The ____ system, the sensation of the body and its movements, is not one sense but many, including discriminative touch (which identifies the shape of an object), deep pressure, cold, warmth, pain, itch, tickle, and the position and movement of the joints.
Receptor: ____ ____ ____. Location: near base of hairs and elsewhere in skin. Responds to: pain, warmth, cold.￼
Free nerve ending
Receptor: ____ ____. Location: hair-covered skin. Responds to: movement of hairs.
Receptor: ____ ____. Location: hairless areas. Responds to: sudden displacement of skin; low-frequency vibration (butter).
Receptor: ____ ____. Location: both hairy and hairless skin. Responds to: sudden displacement of skin; high-frequency vibration.
Receptor: ____ ____. Location: both hairy and hairless skin. Responds to: light touch.
Receptor: ____ ____. Location: both hairy and hairless skin. Responds to: stretch of skin.
Receptor: ____ ____ ____. Location: mostly or entirely in hairless areas, perhaps including genitals. Responds to: uncertain.
Krause end bulbs
A ____ ____ maybe a simple bare neutron ending (e.g., many pain receptors), a modified dendrite (Merkel's discs), an elaborated neuron ending (Ruffini endings and Meissner's corpuscles), or a bare ending surrounded by other cells that modify its function (Pacinian corpuscles).
Stimulation of a touch receptor opens ____ channels in the axon, thereby starting an action potential.
Information from touch receptors in the head enters the central nervous system (CNS) through the ____ ____.
Information from receptors below the head enters the spinal-cord and passes toward the brain through the 31 ____ ____, including 8 cervical nerves, 12 thoracic nerves, 5 lumbar nerves, 5 sacral nerves, and 1 coccygeal nerve.
Each spinal nerve has a ____ component and a ____ component.
sensory : motor
Each spinal nerve innervates (connects to) a limited area of the body called a ____. Each dermatome overlaps one third to one half of the next dermatome.
The various areas of the somatosensory thalamus send their impulses to different areas of the ____ ____ ____, located in the parietal lobe.
primary somatosensory cortex
To parallel strips in the ____ ____ respond mostly to touch on the skin. Two other parallel strips respond mostly to deep pressure and movement of the joints and muscles.
The primary somatosensory cortex is essential for touch experiences. Damage to somatosensory cortex impairs ____ ____.
____, the experience provoked by harmful stimulus, directs your attention toward a danger and holds your attention.
With pain the ____ cortex continues responding as long as the pain lasts.
Pain sensation begins with the least specialised all receptors, a ____ ____ ____.
bare nerve ending
____, the chemical found in hot peppers such as jalapenos, also stimulates the receptors for painful heat. ____ can produce burning or stinging sensations on many parts of your body.
The axons carry pain information have little or __ ____ and therefore conduct impulses relatively slowly, and the range of 2 to 20 m/s.