17.Neuro_PT2_study_guide

Upper Motor Neurons (UMN)

Neurons that originate in the motor strip of the cerebral cortex or brainstem and synapse with lower motor neurons in the spinal cord.

Lower Motor Neurons (LMN)

Neurons with cell bodies in the spinal cord, whose axons extend into the PNS to synapse with muscle fibers at the neuromuscular junction.

Spinal Reflexes

Automatic responses to stimuli mediated by the spinal cord, maintaining posture, muscle tone, and protective responses.

Reflex Arc

Neural circuit in the spinal cord that triggers motor responses without needing CNS input.

Afferent Pathways

Sensory pathways that carry sensory impulses to the CNS.

Efferent Pathways

Motor pathways that carry impulses from the CNS to effector organs.

Sympathetic Nervous System (SNS)

Part of the autonomic nervous system responsible for the body's 'fight or flight' response.

Parasympathetic Nervous System (PSNS)

Part of the autonomic nervous system responsible for 'rest and digest' functions.

Acute Pain

Pain that is sharp and sudden, typically signaling injury or trauma.

Chronic Pain

Persistent pain that lasts longer than expected, often associated with ongoing conditions.

Pain Threshold

The minimum intensity at which a stimulus is perceived as painful.

Pain Tolerance

The maximum level of pain a person can endure before seeking relief.

Endogenous Opioids

Natural pain-relieving chemicals in the body, such as endorphins.

Referred Pain

Pain perceived in a location different from its origin but innervated by the same spinal nerve segment.

Autonomic Nervous System (ANS)

Part of the nervous system that regulates involuntary bodily functions.

Neurotransmitters

Chemical messengers that transmit signals across synapses in the nervous system.

Acetylcholine (ACh)

A neurotransmitter involved in both the peripheral and central nervous systems, acting on cholinergic receptors.

Norepinephrine

A neurotransmitter primarily used in the sympathetic nervous system.

Epinephrine

A hormone and neurotransmitter involved in the fight-or-flight response.

Cholinergic Receptors

Receptors that respond to acetylcholine.

Adrenergic Receptors

Receptors that respond to the catecholamines, norepinephrine and epinephrine.

Beta-1 Receptors

Adrenergic receptors predominantly found in the heart.

Beta-2 Receptors

Adrenergic receptors located in bronchioles and other tissues with beta-mediated functions.

Alpha-1 Receptors

Adrenergic receptors found in vascular smooth muscle that mediate vasoconstriction.

Alpha-2 Receptors

Adrenergic receptors in the CNS that inhibit the release of norepinephrine.

Segmental Organization

The arrangement of spinal nerves and segments that correspond to specific parts of the body.

Pathological Changes in Spinal Cord

Alterations in function resulting from injury, disease, or other disruptions in the spinal cord.

Spinal Cord Injury (SCI)

Damage to the spinal cord that can result in temporary or permanent changes in its function.

Quadriplegia

Paralysis affecting all four limbs, often resulting from cervical spinal cord injuries.

Paraplegia

Paralysis affecting the lower half of the body, typically resulting from thoracic, lumbar, or sacral spinal cord injuries.

Acute Physiological Responses to Pain

Immediate body reactions such as increased heart rate or changes in blood pressure.

Chronic Physiological Responses to Pain

Long-term changes in physiology such as altered stress response and immune function.

Wind-up Phenomenon

Increased sensitivity to pain resulting from repeated stimulation of pain pathways.

Trauma to the Spinal Cord

Physical injury leading to disruption of spinal cord functions.

Degenerative Processes

Gradual deterioration of spinal cord structures, affecting its functioning.

Homeostasis

The body's ability to maintain stable internal conditions despite external changes.

Involuntary Function

Automatic processes regulated by the ANS, such as heart rate and digestion.

Hypothalamus and Brain Stem

Brain regions responsible for integrating autonomic functions and maintaining homeostasis.

Pre-ganglionic Neurons

Neurons that emerge from the spinal cord and synapse in ganglia before reaching target tissues.

Post-ganglionic Neurons

Neurons that travel from ganglia to the target organ.

Ganglia

Clusters of neuronal cell bodies located in the peripheral nervous system.

Thermoregulation

The ability of the body to maintain a stable internal temperature.

Autonomic Dysreflexia

A condition characterized by rapid increase in blood pressure in response to stimuli below the level of a spinal cord injury.

Vasovagal Response

A reflex that causes a sudden drop in heart rate and blood pressure, leading to fainting.

Sensory Neuron

Neurons that transmit sensory information from receptors to the CNS.

Effector Organ

An organ or tissue that produces a response to a stimulus.

Pain Perception Alteration

Changes in how pain is experienced, influenced by various factors including psychosocial elements.