Dorsal columns, anterolateral sensory

The ascending pathway of the DC-ML includes the primary afferent with cell body in the _____

Second order neuron is in the _____ ____ ___ or ____

Fibers _____ as they exit the _____ to form the ____ ___

Third order neuron is in the ____ ___ ___ nucleus of the ____

The termination of the ____ ___ is in the _____ _ region of the ____ cortex (____ ___) Neurons in the ______ region project ____ to the _____ __ region

The ascending pathway of the DC-ML includes the primary afferent with cell body in the DRG

Second order neruon is in the dorsal nuclei cuneatus or gracilis

Fibers cross as the exit the nucleus to form the medial lemniscus

Third order neuron is in the ventral posterior lateral nucleus of the thalamus

The termination of the thalamic inputs is in the somatosensory I region of the ipsilateral cortex (Postcentral gyrus) Neurons in the somatosensory I region project bilaterally to the somatosensory II region

Trigeminal component of the DC-ML system has a primary afferent with cell body in the _____ ____

Second order neuron in the ____ ____ of ____

Fibers from the ____ ____ of ___ cross the ____ and ascend as the ____ ___ adjacent to the ____ ____

Trigeminal component of the DC-ML system has a primary afferent with cell body in the trigeminal ganglion

Second order neuron in the sensory nucleus of V

Fibers from the sensory nucleus of V cross the midline and ascend as the trigeminal lemniscus adjacent to the medial lemniscus

Receptors of the DC-ML system include ____ ___ which are sensitive to ____ and _____ ____

_____ ____ sensitive to ___ of lower ____ than ____ ___ and _____ ____

____ cells which are located at the base of the ___ and sensitive to ___ ___ and ____ ___

____ endings which are located in the ____ and sensitive to ____ ___ and _____ ____

These are ___-____ or ___-____ fibers

Receptors of the DC-ML system include pacinian corpuscles which are sensitive to vibration (deep dermis) and rapidly adapting

Meissner corpuscles sensitive to vibration of lower frequency pacinian corpuscles (dermal papillae) and rapidly adapting

Merkel cells which are located at the base of the epidermis and sensitive to sustained pressure and slowly adapting

Ruffini endings which are located in the dermis and sensitive to sustained pressure and slowly adapting

These are A-beta or A-delta fibers

Receptors of the DC-ML also include ___ ___ which detect ____ ___

_____ ___ ___ which detect ___ ___

____ ____ mechanoreceptors which detect ___ ____

Receptors of the DC-ML also include muscle spindles which detect muscle stretch (Ia)

Golgi tendon organs which detect Muscle tension (Ib)

Joint capsule mechanoreceptors - detect joint angle (AB fibers)

DC-ML receptors image

Somatotopy in the DC and ML?

The primary somatosensory cortex is ____ with respect to ____ ____ ____

3a is ___ ___
3b is _____
1 is ____
2 is ____ __ and ___

The primary somatosensory cortex is partitioned with respect to functional receptor classes

3a is deep tissue
3b is skin
1 is skin
2 is deep tissue and skin

Information encoded by particular cortical neurons includes more than the ____ ___ of the stimulus. For example, some cortical neurons are sensitive only to a ____ ____ and different neurons encode different ____ of ____

Feature extraction by higher order neurons involves combinations of ____ ____

Information encoded by particular cortical neurons includes more than the primary quality of the stimulus. For example, some cortical neurons are sensitive only to a moving stimulus and different neurons encode different directions of movement

Feature extraction by higher order neurons involves combinations of receptive fields

Feature extraction image receptive field

Excitation and inhibition from a cortical neuron field

Some neurons in the somatic sensory cortex are _____ ____

Some neurons in the somatic sensory cortex are directionally sensitive

The neospinothalamic tract projects directly to the ____ and the paleospinothalamic tract relays through the ____ ____ ___ on the way to the ____

The neospinothalamic tract projects directly to the thalamus and the paleospinothalamic tract relays through the brainstem reticular formation on the way to the thalamus

The paleospinothalamic tract originates in ____ ___

This is ___ fibers (____)

It is ____ (___, ____) pain and chemically mediated ____ ___

Goes to the ____ ___, ____, and _____ ____ of the ____ - as well as the _____

The paleospinothalamic tract originates in lamina V

This is C fibers (afferents)

It is Protopathic (slow, burning) pain and chemically mediated pain sources

Goes to the reticular formation, mesencephalon, and intralaminar nucleus of the thalamus as well as the VPL

The neospinothalamic tract originates in ____ ___

This is ___ fibers (____)

This is _____ (___-____) pain and inputs induced by ____ and ____ ___

Goes to ____ ____ ___ (____ and ____ __)

Has a small _____ component

The neospinothalamic tract originates in Lamina I

This is A-delta fibers (afferents)

This is epicritic (well localized) pain and inputs induced by pressure and thermal extremes

Goes to the thalamic relay nuclei (VPL and posterior nuclei)

Has a small uncrossed component

Trigeminal components of the anterolateral tract include the primary afferents (___ and ____ fibers) with cell bodies in the ___ ____

Central process descend as the ____ ___ of ___ to synapse in the ___ ___ of ___

Neurons in the ___ ___ of __ send ____ across the ___ where they join in the _____ tract and project to the ____

_____ modalities synapse in the ____ ____ ____ ___ while _____ components synapse in the _____ _____

Trigeminal components of the anterolateral tract include the primary afferents (C and Adelta fibers) with cell bodies in the trigeminal ganglion

Central process descend as the spinal tract of V to synapse in the spinal nucleus of V

Neurons in the spinal nucleus of V send axons across the midline where they join in the anterolateral tract and project to the thalamus

Epicritic modalities synpase in the ventral posterior medial thalamus while protopathic components synapse in the intralaminar nucleus

Anterolateral tract conducts ____, _____ sensations, ____ touch, ___, ____, and ____ sensations

Anterolateral tract conducts pain, thermal sensations, crude touch, tickly, itch, and sexual sensations

Neurotransmitter associated with sensory afferents?

Substance P

mechanical afferents conducted through ____ ___ fibers

Thermal afferents conducted through _____ _____ fibers

Polymodal nociceptors conducted through ____ fibers

Mechanical afferents conducted through A delta fibers

Thermal afferents conducted through A delta fibers

Polymodal nociceptors conducted through C fibers

The mechanism by which nerve terminals sense specific modalities such as temp and specific chemicals depends on ____ channels which transduce _____, ____, and ____ stimuli into ____ ____ - these are _____ ____ ____ channels

The first to be ID'd was _____ which responds to _____

The mechanism by which nerve terminals sense specific modalities such as temp and specific chemicals depends on TRP channels which transduce thermal, chemical, and mechanical stimuli into inward currents - these are non selective cation channels


The first to be ID'd was TRPV which responds to capsacin

Nocireceptors are activated by compounds released when ___ is _____. They utilize the _____ channels to generate a potential. _____ ___ mediated processes carry sensations described as _____

_____ ____ mediate long lasting or ____ pain

Nocireceptors are activated by compounds released when tissue is damaged. They utilize the TRP channels to generate a potential. A delta mediated processes carry sensations described as epicritic

C fibers mediate long lasting or protopathic pain

Protopathic pain is the type of pain that is more clinically ____ to treat. All the receptors are ____ ___ ____

They can be responsive to ___, _____, _____, or ____ - they can also be _____ by ____ and ______ ___ so they are more responsive - this is called ____

Protopathic pain is the type of pain that is more clinically difficult to treat. All the receptors are free nerve endings

They can be responsive to K+, histamine, bradykinin, or serotonin - they can also be sensitized by prostaglandins and tissue damage so they are more responsive - this is called hyperalgesia

There are no CNS neurons specifically devoted to ____ ____ - instead _____ afferents converge onto the same _____ neurons that mediate ____ ___

The convergence takes place at the ____ of the ____ ___

Lamina _ and _ cells that give rise to the ____ ____ receive ____ input from both ____ and ____ receptors

There are no CNS neurons specifically devoted to visceral pain - instead visceral afferents converge onto the same CNS neurons that mediate somatic sensation

The convergence takes place at the level of the spinal cord

Lamina I and V cells that give rise to the anterolateral tract receive convergent input from both somatic and visceral receptors

The somatic stimulus takes _____ in ____ ___ - thus ____ __ is referred to the _____ ____ from which the ____ input arose

The somatic stimulus takes precedence in central processing - thus visceral pain is referred to the somatic site from which the convergent input arose

The ability of _____ activation to diminish traffic in the ____ pathways is the mechanism for ____ ___ ___ as a pain therapy

The ability of AB activation to diminish traffic in the pain pathways is the mechanism for transcutaneous nerve stimulation as a pain therapy