MCAT Monday: Processing the Environment - Somatosensation



Foundational Concept 6B: The way we think about the world depends on our awareness, thoughts, knowledge, and memories. It is also influenced by our ability to solve problems, make decisions, form judgments, and communicate. Psychological, sociocultural, and biological influences determine the development and use of these different yet convergent processes.

Biological factors underlie the mental processes that create our reality, shape our perception of the world, and influence the way we perceive and react to every aspect of our lives. (via AAMC)


Practice Videos:

Practice Questions:

1. When a cup starts to slip from one’s hand it makes quick vibrations, which are felt through the hand. Which receptor, that is important in perceiving vibration, is being triggered? Choose 1 answer:

  • A: The Merkel receptor, a slow-adapting (SAI) mechanoreceptor that fires to continuous pressure.

  • B: The Ruffini cylinder, a slow-adapting (SA II) mechanoreceptor that fires to continuous pressure.

  • C: The Meissner corpuscle, a fast-adapting (FA I) mechanoreceptor that fires to ‘on’ and ‘off’ stimulus.

  • D: The Pacinian corpuscle, a fast adapting (FA II) mechanoreceptor that fires to ‘on’ and ‘off’ stimulus.

2. A researcher is attempting to test the hypothesis that vibrotaction is important in the perception of fine or closely spaced texture. She uses a 10 Hz vibration stimulus applied to the skin for 7 minutes to adapt the Meissner corpuscle and a 250 Hz stimulus applied for 7 minutes to adapt the Pacinian corpuscle. What effect did adaptation of the Meissner corpuscle and the Pacinian corpuscle have on the ability to perceive texture, based on the chart below? Choose 1 answer: