Do Now: True or False

• Unmyelinated axons conduct signals faster than myelinated axons.

• The body’s internal organs have sensory receptors for pain.

• The body’s sense of touch is primarily processed in the motor cortex located in the frontal lobe.

• Our emotions do not play any part in processing painful sensations.

• Pain information is sent in only one direction – from the body to the brain.

Pain Phenomena Jigsaw

Why do we first feel a stabbing pain, and then later feel an aching pain?

FirstStabbing

Pain

SecondAching

Pain

Why do people feel pain in their arm when they are having a heart attack?

Why do amputees feel pain in their missing limbs?

Mirror Box Therapy

Somatosensory Cortex Missing Input

Phantom Limb Pain

Why do our emotions play a large role in how we perceive pain?

How do medicines that relieve pain work?

Descending pain pathway

Ascending pain pathway

Opioids

OpioidsLocal anesthetics

Local anestheticsAnti-inflammatory drugs

Pain Receptors

Wrap Up: True or False

• Unmyelinated axons conduct signals faster than myelinated axons. – FALSE

• Myelinated axons conduct signals faster than unmyelinated axons.

Wrap Up: True or False

• The body’s internal organs have sensory receptors for pain. – TRUE

Wrap Up: True or False

• The body’s sense of touch is primarily processed in the motor cortex located in the frontal lobe. – FALSE

• The body’s sense of touch is primarily processed in the somatosensory cortex located in the parietal lobe.

Wrap Up: True or False

• Our emotions do not play any part in processing painful sensations. – FALSE

• Our emotions play a large role in processing painful sensations.

Wrap Up: True or False

• Pain information is sent in only one direction – from the body to the brain. – FALSE

• Pain information is sent in two directions – from the body to the brain, AND from the brain to the body.

Pain Phenomena JigsawPain Phenomena What is it? What is the neural

mechanism?

“First” and “Second “Pain

Referred Pain

Phantom Limb

Pain and Emotions

Medications for Pain

Pain Phenomena JigsawPain Phenomena What is it? What is the neural

mechanism?“First” and “Second “Pain

When we experience pain we often feel a “first” pain that is sharp, and a “second” pain that is dull.

The fibers that transmit painful information impact how pain is felt and how quickly it is felt, depending on whether or not those fibers are myelinated.

Referred Pain We experience pain on different parts of our skin, because our brain incorrectly localizes pain from our internal organs to our skin.

Axons from both the skin and the internal organs project to the same projection neuron in the sensory region of the spinal cord.

Phantom Limb Amputees feel pain in their missing limbs.

The absence of normal activation causes the brain to reorganize.

Pain and Emotions Our emotions play a large role in how we perceive pain.

Painful sensations are processed not only in the somatosensory cortex, but also by the insular cortex and cingulate gyrus which are integrate the sensation with our emotions.

Medications for Pain There are multiple drugs that relieve pain.

The brain has a descending pathway that can modulate pain transmission in the spinal cord. Opioids, like morphine work by activating this pathway.