Sensory Pathways and the Somatic Nervous System

Flashcards focused on key concepts from the chapter on sensory pathways and the somatic nervous system.

What does the somatic nervous system (SNS) control?

Controls contractions of skeletal muscles.

What are the two main divisions of the nervous system?

Central Nervous System (CNS) and Peripheral Nervous System (PNS).

What is the function of sensory pathways?

They transmit sensory information from receptors to the CNS.

What is sensation?

The arriving information to the cortex (input).

What is perception?

The conscious awareness of a sensation (processing).

What are the general senses?

Sensitivity to temperature, pain, touch, pressure, vibration, and proprioception.

What are special senses?

Olfaction (smell), gustation (taste), vision, equilibrium (balance), and hearing.

What is receptor specificity?

The particular type of stimulus that a receptor is responsive to.

What is the function of adaptation in sensory receptors?

Reduction of receptor sensitivity due to constant stimulus.

What are Tonic receptors?

Always active, slow-adapting receptors such as pain receptors.

What are Phasic receptors?

Normally inactive, fast-adapting receptors like those for temperature.

What types of sensory receptors respond to pain?

Nociceptors.

What are thermoreceptors sensitive to?

Temperature changes, including warm and cold sensations.

What do mechanoreceptors respond to?

Physical stimuli that distort their plasma membranes.

What is a homunculus?

A functional map of the primary somatosensory cortex representing sensory neuron density.

What pathway carries sensations of fine touch, vibration, pressure, and proprioception?

The Posterior Column Pathway.

What phenomenon describes continued pain from an amputated limb?

Phantom limb syndrome.

What are the roles of the basal nuclei and cerebellum in movement?

They provide coordination and feedback control over movement.

What do proprioceptors monitor?

The positions of skeletal muscles and joints.

How do motor pathways control movements?

By integrated pathways such as the corticospinal pathway, medial, and lateral pathways.

What is the corticospinal pathway responsible for?

Providing voluntary control over skeletal muscles.

What is the function of somatic motor pathways?

They carry motor commands from the motor cortex to the brain stem or spinal cord.

How do upper motor neurons synapse on lower motor neurons?

In the anterior horns of spinal cord gray matter.