The Pain Matrix Flashcards
What is the following a definition of?
An upleasant sensory and emotional experience related to physical tissue injury or the potential for tissue damage to occur
Pain
Pain follows an intricate, variable interaction between ____ factors such as ____, ____ factors and ____ factors
Biological; genetics; psychological, social
The processing of nocicpetive stimuli and the perception of pain involves what?
Multifactorial and multipathway system
What parts of the brain does the Pain Matrix project to? (7)
- Brainstem
- Amyglada
- Hypothalamas
- Thalamus
- Anterior Cingulate Cortex
- Insula
- Somatosensory Cortices
What are the 2 systems that the cortical represenation of pain been divided into?
Lateral pain system and medial pain system
Which signals transfer up the pain matrix when stimulated?
Peripheral Nociceptors
Which cortical representation of pain stimulus is this?
Recieves location and intensity of tissue damage or potential tissue damage
Lateral Pain System
Which cortical representation of pain stimulus is this?
Affective and cognitive responses to the signals
Medial Pain System
Name the structures of the lateral nociceptive system (3)
- Somatosensory cortex
- ventral posterolateral and ventral postermedial nuclei
Name the structures of the medial nociceptive system (11)
- Insula
- Cingulate Cortex
- Prefrontal
- Parietal Cortex
- Amygdala
- Ventral Striatum of the Basal Ganglia
- Hypothalamus
- Intralaminar nuclei
- Periaqueductal gray
- Reticular formation
- Ventral Medulla
The discriminative aspect of understanding pain is what?
Ability to localize the site, timing, and intensity of tissue damage or potential damage
What is the discriminative aspect of pain processed by?
Travels the spinothalamic tract and is processed in the somatosensory cortex via the lateral pain system
What is the motivational-affective aspect of the pain experience?
Effects of pain experience on emotions and behavior
How the is the motivational-affective aspect processed?
Travels in the spinolimbic and spinoreticular tracts and then to emotional system
What is the cognitive-evaluative aspect of the pain experience?
The meaning that the person assigns to the pain
Does the pain matrix generate a top-down or down-top response to nociceptive signals that regulate affecrent nociceptive signals?
Top-down
What is the following a defintion of?
The top-down inhibition of pain signals
Antinociception
What is the following a defintion of?
The top-down amplification of pain signals
Pronociception
What type of pain is this?
- Serves as a warning system and serves to protect from tissue damage
- Lasts for a short period of time and resolves after the noxious stimulus is removed or the tissue injury heals
Acute Pain
What is acute pain detected by?
Sharp localizing pain, dull throbbing pain
What are the 3 types of noxious stimuli?
- Mechanical
- Thermal
- Chemical
What is the following a defintion of?
- First neurons to be activated
- Primary afferents as the noxious stimulus creates potentials that will eventually synapse in the dorsal horn of the spinal cord before making their way to the brain
Nociceptors
Which nociceptor fiber is this?
- Fast and myelinated
- First to recognize and localize pain
- Activated by mechanical and thermal stimulation
A(delta) fiber
What is the following a defintion of?
- Slow and myelinated
- Signals are diffuse and secondary
- activated by chemical reaction
C Fibers
What is the following a defintion of?
- General sensory fibers
- Invovled in pain modulation
A(beta) fibers
How do nociception signals make their way to the spinal cord?
Via the dorsal root and into the dorsal horn
When the A(gamma) axons enter the cord and branch to the levels of the spinal cord where do they go?
They enter the spinal cord through the dorsolateral tract before entering and terminating in the dorsal horn
What are the following characteristics of?
- Synapse with A(gamma) and C fibers
- Encode only for pain stimulti and project to higher centers
Nociceptive-Specific cells
What are the following characteristics of?
- Recieve dynamic input from all types of sensory fibers
- Can encode for a wide range of painful and nonpainful stimuli
Wide Dynamic Range Fibers
What area of the dorsal horn is this?
Where the processing of nociceptive information can be altered by abnormal neural activity or by tissue injury
Laminae I, II, and V
What state of sensory processing in the dorsal horn is this?
Signals resulting from stimuli are accurate
Normal state
What state of sensory processing in the dorsal horn is this?
Touch, pressure, and vibration information is transmitted normally but nociceptive impulses are inhibited
Suppressed State
What state of sensory processing in the dorsal horn is this?
Changes in the quantities and types of neurotransmitters and receptors produce painful response to A(beta), A(delta), and C activity
Sensitized State
What is the following a defintion of?
Sensitized state in which neurons within the central nociceptive pathways exhibit elevated responses to incoming nociceptive and non-nociceptive stimuli
Central Sensitization
Following an acute injury central sensitization is triggered by what?
Peripheral sensitization in nonciceptive afferents
When does central sensitization occur?
In acute pain and chornic pain
Where do axons in the nociceptive-specific cells and wide dynamic neurons decussate?
In the anterior white commisure of the spinal cord
Where do axons in the nociceptive-specific cells and wide dynamic neurons ascend?
In the anterolateral system
What does the anterolateral system consist of?
Fibers carrying pain and temperature from the spinal cord to the thalamus and brainstem
What is the following a definiton of?
Persistent pain that has been identified as pain that persists past the normal time of tissue healing
Chronic Pain
Are the following charactersitics of primary or secondary chronic pain?
- orignates independently of other conditions and is considered a disease
- exists in the absence of tissue damage and has no beneficial biologic function
- central sensitization intiated by gain of function in central nocicepetive pathways resulting in increased pain perception in the absence of tissue damage
Primary chronic pain
What causes primary chronic pain to occur?
Gain of function in the central nociceptive system
Are the following charactersitics of primary or secondary chronic pain?
- Pain that arises as a consequence of another medical condition
- Nociceptive pain arises from stimulation of nociceptors; gain of function in central nociceptive pathways may be present
- neuropathic chronic pain arises from damage to somatosensory system & nociceptors are not stimulated
Secondary Chronic Pain
What is the following a defintion of?
Phenomenon of pain that is percieved as coming from an area of the body that is not directly innervated by the neurons exposed to the noxious stimulus
Referred Pain
