Three famous neurological pathways

Neurological pathways: 

Neurological pathways

3 Pathways to Learn : 

3 Pathways to Learn 2 sensory pathways Dorsal column- Medial Lemniscus (DC-ML) pathway Spinothalamic pathway 1 motor pathway Corticospinal pathway

Sensory pathways: 

Sensory pathways Body Brain Right Left

Motor pathways: 

Motor pathways Body Brain Right Left

Sensory pathways: 

Sensory pathways Body Brain Right Left

Pathways: 

Pathways What kind of information? How many neurons? Where are the cell bodies? Where do you cross the midline (decussate)? Where in the cord does it travel?

DC-ML pathway: 

DC-ML pathway Body Brain Right Left Thalamus Medulla Spinal cord 1 2 3 Stimulus

DC-ML pathway: 

DC-ML pathway Body Brain Right Left Thalamus Medulla Spinal cord 1 2 3 What kind of information? How many neurons? Where are the cell bodies? Where does it decussate? Where in the cord does it travel?

DC-ML- 5 questions: 

DC-ML- 5 questions What kind of information? Fine touch, sensory localization 2 point discrimination Vibration Conscious proprioception How many neurons? 3 Where are the cell bodies? 1 st neuron  dorsal root ganglion 2 nd neuron ipsilateral medulla. Specifically, in the cuneate or gracile nucleus 3 rd neuron contralateral thalamus. Specifically, in the ventral posterolateral nucleus (VPL) Where do you cross the midline (decussate)? At the medulla. The fibers that decussate are the axons of the 2 nd order neuron. These fibers are called internal arcuate fibers After the fibers cross, the fibers that continue to ascend (still part of 2 nd order neuron) are called the medial lemniscus Where in the cord does it travel? Dorsal column (posterior funiculus)

Spinothalamic pathway: 

Body Brain Right Left Thalamus Medulla Spinal cord 1 2 3 Stimulus Spinothalamic pathway

Spinothalamic - 5 questions: 

Spinothalamic - 5 questions What kind of information? Nociception (perceived as pain) Temperature How many neurons? 3 Where are the cell bodies? 1 st neuron  dorsal root ganglion 2 nd neuron ipsilateral dorsal horn 3 rd neuron contralateral thalamus. Specifically, in the ventral posterolateral nucleus (VPL) Where do you cross the midline (decussate)? At the cord at the point of entry ** Where in the cord does it travel? Anterolateral portion of the cord in the white matter

PowerPoint Presentation: 

DC-ML travels through the dorsal column

PowerPoint Presentation: 

1 2 Spinothalamic travels through the anterolateral white matter

Corticospinal pathway: 

Corticospinal pathway Body Brain Right Left Thalamus Medulla Spinal cord 2 1 Skeletal muscles

Corticospinal - 5 questions: 

Corticospinal - 5 questions What kind of information? Voluntary motor activity How many neurons? 2 Where are the cell bodies? 1 st neuron  2/3 are in frontal lobe, 1/3 are in parietal lobe 2 nd neuron contralateral ventral horn Where do you cross the midline (decussate)? At the medulla. Pyramidal decussation Where in the cord does it travel? Lateral funiculus

PowerPoint Presentation: 

Figure 12.34

PowerPoint Presentation: 

Figure 12.35