47 terms

Peripheral Nervous System: sensory

receptors associated with the general senses
specialized endings of pseudodendrites of first order sensory neurons (pseudounipolar neurons) associated with skin and organ and body walls. They are sensitive to specific changes in the internal or external environent. They differ in structure, thresholds and locations.
exteroceptors and enteroceptors
Types of receptors
types of exteroceptors
nociceptors, thermoreceptors, mechanoreceptors would be categorized as this type of receptor.
These are found in the skin and interact with the external environment
These receptor consist of free nerve endings. They respond to any extreme stimuli and generate impulses interpreted as pain. They are stimulated by tissue damage and low oxygen and extremes. They are particularly sensitive to bradykinin, the most painful substance known.
These receptors respond to changes in temperature.
light touch, regular touch, and pressure
types of mechanoreceptors
Meissner's corpuscles
Which receptor detects light touch in hairless portions of the skin and by root hair plexuses where hairs are present
free nerve endings or Merkel's discs
This receptors detects regular touch
Ruffini's and Pacinian corpuscles
These receptor detects pressure
These receptors supply the body's interior
visceroceptors and proprioceptors
Types of enteroceptors
nociceptors, pressoreceptors, and chemoreceptors
Types of visceroceptors
These receptors are found in the walls of certain blood vessels (carotid and aortic sinuses) and detect change in blood pressure.
These receptors detect changes in chemical concentrations.
In the hypothalamus, these receptors detect body fluid concentrations (hypertonic vs hypotonic)
In the hypothalamus these receptors detect blood sugar levels
These are mechanoreceptors that detect changes in muscle contraction and joint movement (concerned with the position of the body).
golgi tendon organs
detect excessive muscle tension
muscle spindles
detect stretch and movement of muscle tissue
Receptor adaptation
When, after continuous stimulation, receptors fail to respond. In order to avoid adaptation, change in the stimulus must exceed the rate of adaptation. Stimulation may exceed the ability of the receptor to adapt. Receptors vary in their ability to adapt.
nociceptors and proprioceptors
These receptors are slow adapters
thermoreceptors and touch receptors
These receptors are fast adapters
first order sensory neurons
These neurons are psudounipolar neurons in the periphery that have receptors that detect change in the environment.
dorsal root ganglia
It houses cell bodies of 1st order sensory neurons
2nd order sensory neurons
These neurons typically have their cell bodies in the posterior horn of gray matter and have axons that transmit impulses up the spinal cord to the thalamus.
3rd order sensory neurons
These neurons usually have their cell bodies in the thalamus and have axons that extend from the thalamus to the postcentral gyrus of the cortex
referred pain
This is the perception that pain is felt in a part of the body different from the part that is actually generating the pain.
referred pain
It is an inability to project properly. It probably involves an area of the body that is less familiar, convergence of different afferent neurons onto the same seconday neuron, commonly associated with decaying teeth, appendicitis, and heart attack.
root hair plexuses
These receptor detects light touch where hairs are present
These receptors are associated with the walls of internal organs
In the medulla oblongata and in the carotid and aortic bodies, receptors detect carbon dioxide, oxygen and hydrgoen ions.
Osmoreceptors and glucoreceptors
Types of chemoreceptors
These receptors are associated with skeletal muscle, tendons and joints
Golgi tendon organs
These parts of the body detect excessive muslce tension
Muscle spindles
These parts of the body detect stretch and movement of muscle tissue
1st order sensory neurons
These neurons have psedodendrites (peripheral processes) that extends from the peripher to the brain stem nuclei of cranial nerves and the dorsal root ganglia of spinal nerves.
1st order sensory neurons
These neurons are the first neurons in the pathway that leads ultimately to the somatosensory cortex on the postcentral gyurs of the brain.
1st order sensory neurons
Axons of these neurons extend from the cell body to the posterior horn of gray matter in the spinal cord.
1st order sensory neurons
the axons of these neurons synapse with a second order sensory neuron in the posterior horn.
2nd order sensory neurons
With their axons in the spinocerebellar tract, these neurons transmit impulses (proprioception) to the cerebellum
This part of the brain crudely determines the type and location of the sensation.
This part of the brain tempers one's emotional reaction to the sensation
cerebral cortex (postcentral gyrus)
this part of the brain specifically determines the source and kind of sensation
cerebral cortex (postcentraly gyrus)
This part of the brain determines the intensity of the sensation
cerebral cortex (postcentral gyrus)
This part of the brain projects the sensation back to its source
These receptors are housed in a special structure of special sense (eye, ear, tongue, nose)