definitions

Question 1

specificity

Answer 1

each sensory receptor responds only to a particular stimulus

Question 2

adequate stimulus

Answer 2

only a threshold stimulus can activate a receptor

Question 3

Adaptation of receptors

Answer 3

When a stimulus of constant strength is applied to the receptor, the frequency of action potential in its sensory nerve decreases over a period

Question 4

Type of stimulus

Answer 4

A particular sensory receptor is sensitive to one type of stimuli
- labelled line principle

Question 5

Weber-Fechner law

Answer 5

Frequency of action potentials (magnitude of sensation) generated in a nerve fiber is directly proportional to the log intensity of the stimulus

Question 6

Intensity discrimination is brought about through two ways:

Answer 6

1. Strength of stimulus (intensity of stimulus)
2. Increasing the number of receptors being stimulated (recruitment of sensory units)

Question 7

Location of stimulus

Answer 7

acuity is increased when the receptive field is smaller and there is more overlap among the sensory units

• Receptive field and sensory unit is larger and so to discriminate two points of stimuli is difficult ( example: internal organs)
• Receptive field and sensory unit is smaller and so to discriminate two points of stimuli is easier (Example: tip of the finger)

Question 8

Law of projection

Answer 8

Stimulation of sensory nerve fiber anywhere along its course produces the specific sensation which is refferred to the location of the receptor

Question 9

Duration of stimulus

Answer 9

Adaptation-stimulus of constant strength over a period -frequency of action potentials generated reduces