Anatomy and Physiology - Sensory, Motor, and Integrative Systems

Flashcards based on Anatomy and Physiology lecture notes, focusing on the sensory, motor, and integrative systems.

Nervous System

Senses internal/external environments, conveys sensations to CNS, determines motor responses.

Sensation

Detection of changes in external/internal environment.

Perception

Conscious awareness and interpretation of sensations.

Sensory Modality

Unique type of sensation (somatic, visceral, smell, taste, vision, etc.).

Transduction

Convert stimulus energy into graded potential.

Free Nerve Endings

Bare dendrites for pain, temperature, tickle, itch, and some touch.

Encapsulated Nerve Endings

Dendrites in capsule for pressure, vibration, and some touch.

Separate Cells

Receptor cells synapse with sensory neurons in retina, inner ear, and taste buds.

Sensory Graded Potentials

Amplitudes vary with stimulus intensity.

Generator Potentials

Generate action potentials in sensory neuron’s axon.

Receptor Potentials

Trigger neurotransmitter release across synapse with sensory neuron.

Exteroceptors

Receptors at external surface; sensitive to external stimuli.

Interoceptors

Receptors in vessels, organs, and nervous system; internal environment info.

Proprioceptors

Receptors in muscles, tendons, joints, and inner ear; body position info.

Mechanoreceptors

Detect mechanical stimuli; touch, pressure, vibration, proprioception, etc.

Thermoreceptors

Detect temperature changes.

Nociceptors

Respond to painful stimuli from tissue damage.

Photoreceptors

Detect light on retina.

Chemoreceptors

Detect chemicals in mouth, nose, and body fluids.

Osmoreceptors

Sense osmotic pressure of body fluids.

Adaptation in Sensory Receptors

Decrease in receptor sensitivity during constant stimulus.

Somatic Sensations

Sensations from skin, membranes, muscles, tendons, joints, and inner ear.

Cutaneous Sensations

Somatic sensations from skin stimulation.

Four Modalities of Somatic Sensations

Touch, thermal, pain, and proprioceptive sensations.

Tactile Sensations

Activation of encapsulated mechanoreceptors for touch, pressure, and vibration.

Thermal Sensations

Activation of thermoreceptor free nerve endings.

Pain Sensations

Activation of nociceptor free nerve endings.

Somatic Fast Pain

Precisely localized pain.

Somatic Slow Pain

Diffuse pain from a larger skin area.

Referred Pain

Pain from skin area served by same spinal cord segment as embryologic origin.

Proprioceptive Sensations

Activation of proprioceptors for awareness of movements and position.

Muscle Spindles

Detect muscle length; maintain tone and stimulate contraction when stretched.

Tendon Organs

Detect tendon tension; reflex decreases muscle tension.

Joint Kinesthetic Receptors

Detect joint pressure, position, and movement.

Somatic Sensory Pathways

Relay information from somatic sensory receptors to cerebral cortex and cerebellum.

First-Order Neuron

Impulse from somatic receptor to CNS.

Second-Order Neuron

Decussate, carry impulse to thalamus.

Third-Order Neuron

Impulse from thalamus to postcentral gyrus on same side.

Posterior Column - Medial Lemniscus Pathway

Conducts nerve impulses for conscious proprioception, touch, and vibration.

Spinothalamic Pathway

Conducts impulses for pain, temperature, tickle, and itch.

Spinocerebellar Tract

Major route for proprioceptive impulses to cerebellum.

Primary Somatosensory Area

Receives sensory input from different body parts.

Primary Motor Area

Areas serve different body muscles unequally.

Lower Motor Neurons

Extend from brain and spinal cord to skeletal muscles.

Local Circuit Neurons

Coordinate rhythmic activity in muscle groups.

Upper Motor Neurons

Maintain muscle tone, posture, and balance.

Basal Nuclei Neurons

Initiate, terminate, and suppress movements.

Cerebellar Neurons

Coordinate movements, posture, and balance.

Direct Pathways

Control precise movements of hands and feet.

Lateral Corticospinal Pathway

Controls skilled movements of the hands and feet; decussates at medulla.

Anterior Corticospinal Pathway

Control movements of trunk/proximal limbs; decussate at spinal cord levels.

Corticobulbar Pathway

Control skeletal muscles of the head; some decussate.

Indirect Pathways

Axons extend from brain stem to spinal nerve.

Modulation of Movement by the Basal Nuclei

Respond with feedback signals through the thalamus.

Modulation of Movement by the Cerebellum

Monitors intentions/movements; sends correcting feedback if discrepancy.

Reticular Activating System (RAS)

Receives input from sensory receptors, eyes, and ears (not olfactory).

Learning

Ability to acquire new information or skills.

Memory

Ability to store and recall information or skills.

Immediate Memory

Recall ongoing experiences for a few seconds.

Short-Term Memory

Recall info for seconds to minutes; depends on brain events at time.

Long-Term Memory

Lasts days to years, and can be retrieved.