QS Study

Receptors are a part of the neuron or specialized cells which can generate an action potential in the neuron. It is an organ or cell able to respond to light, heat, or other external stimulus and transmit a signal to a sensory nerve. Receptors are often located in the sense organs, such as the ear, eye, and skin. Each organ has receptors sensitive to particular kinds of stimulus.

Properties of receptor –

Differential sensitivity: Every receptor is specific for specific stimulus.

Relation with the strength of stimulus: Sensation cc strength of the stimulus.

Mullen doctrine of specific nerve energy: The sensation evoked by any stimulation, the impulse generated in the receptor depends upon the specific part of the brain that ultimately activated.

Projection: Brain is stimulated but the conscious sensation is felt in the location of the receptor.

Recruitment: Increase stimulus causes addition of new stimulated receptors.

Adaptation: When a main tired and constant stimulation is applied to receptor the frequency of discharge from that receptor will gradually decline.

  • Rapid-Pacinian corpuscle
  • Slowly muscle spindle.

Intensity discrimination: The magnitude of sensation perceived is proportional to the log of the intensity of the stimulus and this is called “Weber Fechner law.”