Dr. Jacqueline A. Tickle Touch Lecture

These flashcards cover key concepts and details from Dr. Jacqueline Tickle's lecture on touch and sensation, focusing on mechanoreceptors and their significance in the sensory system.

What are the learning expectations of this lecture?

By the end of the lecture, students will be able to describe the neuronal basis of touch, explain the pathway from mechanoreceptors to the cortex via the thalamus, and apply this knowledge to higher-level processing in the somatosensory cortex.

What is the importance of touch in human experience according to David J. Linden?

Touch is crucial for human development, influencing everything from consumer choice to healing, and is integral to our unique human experience.

What are the four main types of cutaneous mechanoreceptors?

Meissner corpuscle (RA1), Merkel cells (SA1), Pacinian corpuscle (RA2), and Ruffini endings (SA2).

What type of information do SA1 fibers encode?

SA1 fibers encode form and pressure, including edges.

How do RA2 fibers respond to vibration?

RA2 fibers encode vibration, producing spikes at onset and offset of pressure stimuli, as well as during vibration stimuli.

What fiber types are involved in the mechanoreceptors?

C fibers, A-delta fibers, A-beta fibers, and A-alpha fibers.

What role does the thalamus play in the sensory pathway?

The thalamus acts as a relay station for sensory information before it is processed in the cortex.

What happens in the spinal cord regarding afferent fibers?

Afferent fibers synapse in the dorsal horn of the spinal cord, and information is segregated by fiber-type within the horn.

Why are SA2 fibers considered super-sensitive?

SA2 fibers are super-sensitive to stretch and play a role in hand shape perception and 3D shape.

What can the mechanoreceptors and their responses tell us when someone grips an object?

Mechanoreceptors work together to sense grip force, load force, hand posture, and vibrations during force application.