Neuroscience: DCML Pathway Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What type of sensory information is primarily carried by the DCML pathway?

Pain and temperature

Vibration, proprioception, and fine touch (correct)

Visual and auditory stimuli

Coarse touch and pressure

Where does the decussation of the DCML pathway occur?

At the level of the lumbar region

In the spinal cord

Within the thalamus

In the lower medulla (correct)

Which structures are involved in transmitting information through the DCML pathway?

Spinocerebellar tracts

Lateral corticospinal tract

Cuneate and Gracile Fasciculi (correct)

Anterior spinothalamic tract

What is the sequence of brain structures that the DCML pathway synapses with after decussation?

Thalamus, parietal cortex (C) Signup and view all the answers

Which pathway runs on the ipsilateral side of the spinal cord before decussation?

DCML pathway (D) Signup and view all the answers

Which type of sensation requires the integrity of the contralateral cerebral sensory cortex for correct perception?

Vibration sensations (A) Signup and view all the answers

What is the primary role of the posterior roots of spinal nerves?

Conduct sensory information to the spinal cord (C) Signup and view all the answers

Which pathway is responsible for carrying information about pain and temperature?

Spinothalamic pathway (C) Signup and view all the answers

What does the term 'decussate' refer to in the context of sensory pathways?

The crossing over of nerve fibers to the opposite side (C) Signup and view all the answers

Which of the following is not a cortical sensation?

Proprioception (C) Signup and view all the answers

How are sensations of itching and tickling processed in the nervous system?

Via the spinothalamic pathway (C) Signup and view all the answers

What ability is assessed when a patient can recognize a key placed in their hand without seeing it?

Tactile Recognition (B) Signup and view all the answers

Which of the following sensations is processed primarily at the contralateral thalamus?

Temperature (C) Signup and view all the answers

What is a common cause of dorsal radiculopathy?

Herniated disc (A) Signup and view all the answers

Which neurological syndrome is characterized by impaired vibration and proprioception below the level of the lesion?

Posterior Cord Syndrome (A) Signup and view all the answers

Which condition is described by damage to multiple peripheral nerves in a symmetrical manner?

Polyneuropathy (D) Signup and view all the answers

What symptom would NOT typically be associated with an impairment in the dorsal root?

Bilateral ataxia (C) Signup and view all the answers

Which of the following conditions is NOT a cause of Posterior Cord Syndrome?

Vascular insufficiency (B) Signup and view all the answers

Which symptom is typically spared in Posterior Cord Syndrome unless the lesion progresses?

Motor function (D) Signup and view all the answers

What type of nerve damage involves only a single nerve?

Mononeuropathy (A) Signup and view all the answers

Which of the following is a characteristic symptom of dorsal radiculopathy?

Ipsilateral muscle weakness (C) Signup and view all the answers

What causes Anterolateral Cord Syndrome?

Anterior spinal artery occlusion (B) Signup and view all the answers

Which sensory modalities are preserved in Central Cord Syndrome?

Touch, vibration, and proprioception (C) Signup and view all the answers

Which tract is least affected by lesions of the Medulla Oblongata?

Dorsal columns (D) Signup and view all the answers

What is a clinical feature of Anterolateral Cord Syndrome?

Bilateral impairment of pain and temperature perceptions (D) Signup and view all the answers

Which syndrome features dissociated sensory loss?

Central Cord Syndrome (C) Signup and view all the answers

Who is most likely to be affected by the consequences of lateral medullary infarction?

Patients with circulatory system disorders (A) Signup and view all the answers

What effect does Anterolateral Cord Syndrome have on the corticospinal tract?

It is completely affected (B) Signup and view all the answers

Which clinical sign is typical of Central Cord Syndrome as it expands?

Lower motor neuron signs below the lesion (C) Signup and view all the answers

What is the primary function of the trigeminal nerve (CN V)?

Transmitting sensations of pain, temperature, and touch (A) Signup and view all the answers

What is the clinical feature associated with lesions of the Medulla Oblongata?

Impaired pain and temperature perception (B) Signup and view all the answers

Where does sensation from the trigeminal nerve's nuclei decussate before ascending to the thalamus?

Within the trigeminal nucleus in the pons (D) Signup and view all the answers

Where is sensory impairment localized with a unilateral lesion of the pons or midbrain?

Contralateral to the lesion (C) Signup and view all the answers

Which part of the body does the somatosensory cortex primarily receive sensations from?

The contralateral side of the body (A) Signup and view all the answers

Which sensory pathway is primarily responsible for transmitting fine touch and proprioception?

DCML pathway (D) Signup and view all the answers

What are common causes of Thalamic Pain Syndrome?

Stroke, multiple sclerosis, tumors, and trauma (B) Signup and view all the answers

What is a clinical consequence of a parietal lobe lesion?

Loss of discriminative sensory function contralateral to the lesion (A) Signup and view all the answers

In a lesion affecting a peripheral nerve, what kind of sensory impairment would you expect?

Impairment of multiple modalities in a corresponding dermatomal distribution (A) Signup and view all the answers

Which of the following distinguishes the sensory effects of a Medulla Oblongata lesion from a Thalamic Pain Syndrome?

Ipsilateral face and contralateral body effects (C) Signup and view all the answers

Which structure directly follows the trigeminal nerve in the ascending sensory pathway?

Thalamus (B) Signup and view all the answers

In Thalamic Pain Syndrome, what sensory modality is primarily affected?

All sensory modalities contralateral to the lesion (D) Signup and view all the answers

What is the role of the dorsal ganglion in sensory pathways?

To relay afferent sensory information to the spinal cord (D) Signup and view all the answers

How is pain and temperature perception affected by a lesion in the Medulla Oblongata?

Impaired ipsilaterally on the face (A) Signup and view all the answers

Which of the following best describes the pathway of sensations from the trigeminal nerve to the somatosensory cortex?

CN V → Pons → Thalamus → Somatosensory Cortex (B) Signup and view all the answers

What is typically preserved in a parietal lobe lesion despite sensory loss?

Both pain and temperature (B) Signup and view all the answers

Study Notes

Sensory Syndromes

This lecture covers sensory pathways and syndromes.
Includes classifications based on the location of the lesion affecting the sensory system.

Types of Sensations

Pain, touch, temperature, vibration, and proprioception are discussed.
Cortical sensations are tested with the patient's eyes closed, including two-point discrimination, tactile recognition, graphesthesia, and localization.

Classification

Vibration, proprioception, and cortical sensations require the contralateral cerebral sensory cortex for accurate perception.
Pain, temperature, and touch are processed in the contralateral thalamus.

Anatomical Review

Spinal Nerves: Each spinal nerve has an anterior and a posterior root. Anterior roots carry motor information, originating from anterior horns and exiting towards muscles. Posterior roots carry sensory information from receptors to the posterior horns, containing a sensory ganglion.
Sensory Pathways:
- The spinothalamic pathway carries pain, temperature, and crude touch, decussating (crossing to the opposite side) in the spinal cord and ascending to the thalamus.
- The dorsal column-medial lemniscus (DCML) pathway carries vibration, proprioception, and fine touch, ascending ipsilaterally (same side) in the spinal cord, decussating in the medulla, and synapsing in the thalamus and parietal cortex.
Cranial Nerves: The trigeminal nerve (CN V) conveys sensory information from the face, with its ophthalmic, maxillary, and mandibular divisions. Afferent signals travel to the trigeminal nucleus in the pons, decussating and ascending to the thalamus and somatosensory cortex.

Sensory Syndromes:

Classification by Location: Lesions in peripheral nerves, dorsal roots, spinal cord, brainstem, thalamus, and the somatosensory cortex each result in unique patterns of sensory loss.
Peripheral Nerve Lesions: Injury to a peripheral nerve leads to sensory impairment across all modalities in the corresponding dermatome.
- Mononeuropathy: Damage to a single nerve
- Polyneuropathy: Symmetrical damage to multiple peripheral nerves
Dorsal Root Disorders: Often caused by herniated discs, resulting in ipsilateral (same side) radicular pain (tingling or electrical), hypoesthesia (reduced sensation), and muscle weakness.
Spinal Cord Syndromes:
- Posterior Cord Syndrome: Affects the DCML pathway, sparing spinothalamic and corticospinal fibers. Causes include vitamin B12 deficiency and multiple sclerosis. Clinical features include bilateral loss of vibration and position sense below the level of the lesion.
- Anterolateral Cord Syndrome: Affects spinothalamic and corticospinal tracts, sparing dorsal columns. Often caused by anterior spinal artery occlusion. Clinical features include bilateral impairment of pain and temperature below the level of the lesion, plus paraplegia or tetraplegia with hypotonia and hyporeflexia.
- Central Cord Syndrome: Affects spinothalamic fibers at the level of decussation, sparing the DCML pathway. Often due to syringomyelia or spinal tumours. Clinical features include dissociated sensory loss (pain and temperature lost, touch preserved).
Brainstem Lesions:
- Medulla Oblongata Lesions: Commonly due to posterior inferior cerebellar artery occlusion. Affect the trigeminal nerve and spinothalamic tracts (ipsilateral facial and contralateral body pain/temp). Clinical features include impaired pain/temp. ipsilateral on the face and contralateral on the body (Harlequin syndrome).
- Pons and Midbrain Lesions: Unilateral lesions result in sensory impairment contralateral to the side of the lesion.
Thalamic Lesions: Thalamic pain syndrome, causing impairment of all sensory modalities on the opposite side of the body (contralateral). Symptoms may include hyperpathia (excessive sensitivity to pain).
Somatosensory Cortex Lesions: Parietal lobe lesions cause loss of discriminative sensory function on the opposite side of the body (contralateral). Pain/temp/touch are relatively preserved.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on the Dorsal Column-Medial Lemniscal (DCML) pathway in the nervous system. This quiz covers key aspects such as sensory information types, decussation, and structures involved. Challenge your understanding of how sensory modalities are processed in the brain.