NeuroscienceLesson 2 of 3 in the course The Somatic Nervous System

Sensory Pathways, Thalamic Relays, and Cortical Processing

5 flashcards · 4 quiz questions · 5 match pairs · 5 fill-in sentences · English

Save course
Lesson progress
0 / 5

Your progress is kept in this browser only.Sign up to save it

Summary

This lesson follows somatic sensory information from receptors toward the brain. Comparing the major pathways helps explain how the CNS distinguishes touch and body position from pain and temperature.

An ascending pathway carries sensory information from the periphery toward the brain. Many pathways use a chain of three neurons. The first neuron brings information from a receptor into the CNS; the second relays it toward the thalamus; and the third projects from the thalamus to the cerebral cortex. The thalamus is a major relay point before conscious sensory processing in the cortex.

All flashcards

What is the usual three-neuron plan for an ascending sensory pathway?
A first neuron carries receptor input into the CNS, a second relays toward the thalamus, and a third projects to the cerebral cortex.
Where does the second neuron cross in the dorsal column system?
It crosses the midline in the medulla before ascending as the medial lemniscus.
What does the vestibulo-ocular reflex do?
It helps keep images stable on the retina during head and body motion.
How does the ventral visual stream differ from the dorsal stream?
The ventral stream supports visual identification and significance; the dorsal stream supports spatial location and visually guided movement.
What is prosopagnosia?
An impairment in recognizing people by their faces.

Quiz questions

  1. How does the brain use auditory input to help locate a sound?Answer: It compares differences in sound arrival time and intensity between the ears.
  2. What is unusual about the initial route of olfactory information to the cerebral cortex?Answer: Olfactory tract axons can reach the cortex without the usual initial thalamic relay.
  3. Which function is most associated with the dorsal visual stream?Answer: Locating objects and guiding movement in response to visual input.
  4. How can binocular vision provide information about depth?Answer: The brain compares slightly different images received by the two eyes.

Based on Anatomy and Physiology 2e by J. Gordon Betts, Kelly A. Young, James A. Wise, Eddie Johnson, Brandon Poe, Dean H. Kruse, Oksana Korol, Jody E. Johnson, Mark Womble, Peter DeSaix (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.

More in Neuroscience

All Neuroscience lessons
NeuroscienceHuman Sensory Systems: Receptors, Transduction, and Sensory Pathways5 flashcards · 5 quiz questions · 4 gamesPlay free →NeuroscienceForebrain and Medullary Control of Autonomic Responses5 flashcards · 5 quiz questions · 4 gamesPlay free →NeuroscienceSynaptic Plasticity: Mechanisms, Timescales, and Regulation5 flashcards · 4 quiz questions · 4 gamesPlay free →NeuroscienceNeuroplasticity: Mechanisms, Learning, Rehabilitation, and Adaptation5 flashcards · 5 quiz questions · 4 gamesPlay free →NeuroscienceGABA Signaling: Receptors, Development, Metabolism, and Pharmacology5 flashcards · 5 quiz questions · 4 gamesPlay free →NeuroscienceBrain and Spinal Cord: Neural Organization, Function, and Measurement5 flashcards · 5 quiz questions · 4 gamesPlay free →