CNS spinal cord

What is the conus medullaris?

The cone-shaped end of the spinal cord located between the L1-L2 vertebrae.

What is the cauda equina?

A 'horse-tail' of nerve roots that extend below the conus medullaris.

What is the filum terminale?

thin extension of pia mater that anchors the spinal cord to the coccyx.

Where is the epidural space located?

Between vertebrae and dura mater; contains fat and blood vessels.

What is a clinical use of the epidural space?

Epidural anesthesia is delivered here.

What is the subdural space?

A potential space between dura and arachnoid mater; it can be a site for hematomas.

What is located in the subarachnoid space?

Cerebrospinal fluid (CSF) is contained here.

What procedure is performed in the subarachnoid space?

Lumbar puncture (CSF collection) and spinal anesthesia.

What does the anterior horn contain?

Somatic motor neurons for skeletal muscle control.

Where is the lateral horn located and what does it contain?

Located at the side of gray matter (T1-L2 region), contains autonomic neurons for smooth muscle, cardiac muscle, and glands.

What is the function of sensory neurons in the posterior horn?

They are responsible for processing incoming sensory signals.

What is the anterior funiculus responsible for?

It contains motor pathways for voluntary movement.

What does the lateral funiculus contain?

It contains both motor and sensory pathways.

What is the function of the posterior funiculus?

It contains sensory pathways for touch and proprioception.

What do first-order neurons in the posterior column do?

They carry touch and proprioception signals from sensory receptors to the medulla.

Where do third-order neurons in the posterior column go?

They travel from the thalamus to the somatosensory cortex.

What is the function of the spinothalamic pathway?

It carries pain and temperature signals.

Where do first-order neurons of the spinothalamic pathway start and where do they go?

They start at sensory receptors and travel to the posterior horn.

What is the function of the spinocerebellar pathway?

It carries unconscious proprioception signals.

Where do lower motor neurons start in the corticospinal descending pathway?

They start in the anterior horn.

What is the role of upper motor neurons?

They control voluntary movement and start in the primary motor cortex.

Why does damage to the left side of the brain affect the right side of the body?

Because sensory and motor pathways decussate (cross over) to the opposite side.

Where does decussation occur for motor pathways?

In the medulla for the corticospinal tract.

Where does decussation occur for the spinothalamic tract?

In the spinal cord.

Where does decussation occur for the posterior column pathway?

In the medulla.