True about Galvanic Skin Response: (PGI June 2009)
**Core Concept**
Galvanic Skin Response (GSR) is a physiological phenomenon that measures the electrical conductivity of the skin, which changes in response to emotional arousal, stress, or other stimuli. It is a type of psychophysiological response that can be used in various applications, including lie detection and emotional state assessment.
**Why the Correct Answer is Right**
GSR is an autonomic nervous system response that involves the release of acetylcholine from the eccrine glands in the skin, leading to an increase in sweat gland activity. This increase in sweat gland activity results in a decrease in the electrical resistance of the skin, making it more conductive to electrical currents. The GSR response is often used in conjunction with other measures, such as heart rate and blood pressure, to assess a person's emotional state or detect deception.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the mechanism of GSR. While it is true that GSR is an autonomic nervous system response, it is not primarily a response to visual stimuli.
**Option B:** This option is incorrect because it is not a specific or accurate description of the GSR response. While it is true that GSR can be influenced by emotional arousal, it is not the only factor that affects the response.
**Option C:** This option is incorrect because it does not accurately describe the physiological basis of GSR. While it is true that GSR involves changes in the skin, it is not primarily a response to changes in skin temperature.
**Option D:** This option is incorrect because it is not a specific or accurate description of the GSR response. While it is true that GSR can be used in various applications, it is not the only use of the response.
**Clinical Pearl / High-Yield Fact**
One important clinical application of GSR is in the assessment of anxiety disorders, where an abnormal GSR response can be used as an indicator of increased anxiety or stress.
**Correct Answer:** None of the above