The Tectospinal Pathway

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The Tectospinal Pathway

• "I like a woman with a head on her shoulders. I
  hate necks."
• -Steve Martin

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Introduction

• This descending pathway plays a large role in the
  orientation of head movement to visual cues and
  eye-head coordination
• It originates from the deep layers of the
  superior colliculus, crosses ventral to the
  central gray matter (Dorsal Tegmental
  Decussation), and descends contralaterally near
  the medial longitudinal fasciculus.

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Distribution
The distribution along the spinal cord is mainly
to cervical Motor neurons - to the muscles of
the neck and shoulder girdle.
From http//danke.com/Orthodoc/neck.html
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The Superior ColliculusEye-Head Coordination

• The superior colliculus receives input from the
  retina and the visual
• cortex. Output from its deepest layer begins
  the Tectospinal path.

Output to Tectospinal Tract
From Retina and Visual cortex
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Switching Sides
Superior Colliculus Medial Longitudinal Fascicul
us Dorsal Tegmental Decussation
In the caudal portion of the midbrain the fibers
cross ventral to the central gray matter and
descend contralaterally.
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Going Down..
Medial Lemniscal Tectospinal MLF
The fibers continue down the spine between the
Medial Lemniscal and the MLF pathways.
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Exiting the cord
At the cervical level, the fibers synapse in the
medial portion of the ventral horn. The axons
leaving the ventral horn serve to excite muscles
in the neck.
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And now for the movie.