<table class="infobox infobox-cell">
<tr>
<th class="infobox-header" colspan="2">Pretectal Nuclei</th>
</tr>
<tr>
<td class="label">Location</td>
<td>Dorsal midbrain, rostral to superior colliculus</td>
</tr>
<tr>
<td class="label">Components</td>
<td>Olivary pretectal nucleus, nucleus of the optic tract, posterior pretectal nucleus, anterior pretectal nucleus</td>
</tr>
<tr>
<td class="label">Primary Function</td>
<td>Pupillary light reflex, optokinetic nystagmus</td>
</tr>
<tr>
<td class="label">Key Inputs</td>
<td>Retinal ganglion cells, visual [cortex](/brain-regions/cortex), superior colliculus</td>
</tr>
<tr>
<td class="label">Clinical Relevance</td>
<td>Vertical gaze palsy in PSP, Parinaud syndrome</td>
</tr>
<tr>
<td class="label">Taxonomy</td>
<td>ID</td>
</tr>
<tr>
<td class="label">Allen Brain Cell Atlas</td>
<td>[Search](https://portal.brain-map.org/atlases-and-data/bkp/abc-atlas)</td>
</tr>
<tr>
<td class="label">Cell Ontology (CL)</td>
<td>[Search](https://www.ebi.ac.uk/ols4/ontologies/cl/)</td>
</tr>
<tr>
<td class="label">Human Cell Atlas</td>
<td>[Search](https://www.humancellatlas.org/)</td>
</tr>
<tr>
<td class="label">CellxGene Census</td>
<td>[Search](https://cellxgene.cziscience.com/)</td>
</tr>
<tr>
<td class="label">Marker</td>
<td>Expression Pattern</td>
</tr>
<tr>
<td class="label">Calbindin</td>
<td>Diffuse pretectal neurons</td>
</tr>
<tr>
<td class="label">Parvalbumin</td>
<td>Direction-selective neurons</td>
</tr>
<tr>
<td class="label">c-Fos</td>
<td>Light-responsive neurons</td>
</tr>
<tr>
<td class="label">Melanopsin</td>
<td>Intrinsically photosensitive cells</td>
</tr>
<tr>
<td class="label">GAD65/67</td>
<td>GABAergic interneurons</td>
</tr>
<tr>
<td class="label">VGLUT2</td>
<td>Glutamatergic projection neurons</td>
</tr>
<tr>
<td class="label">Pathological Change</td>
<td>Clinical Manifestation</td>
</tr>
<tr>
<td class="label">Pretectal neuronal loss</td>
<td>Vertical saccade slowing</td>
</tr>
<tr>
<td class="label">Globose neurofibrillary tangles</td>
<td>Downgaze limitation</td>
</tr>
<tr>
<td class="label">Posterior commissure gliosis</td>
<td>Loss of vertical vestibulo-ocular reflex</td>
</tr>
<tr>
<td class="label">Pretectal [tau](/proteins/tau) pathology</td>
<td>Reduced OKN response</td>
</tr>
</table>
The pretectal nuclei are a group of midbrain nuclei located at the junction of the diencephalon and mesencephalon, immediately rostral to the superior colliculus. These nuclei are essential for processing visual information related to pupillary light reflexes, optokinetic responses, and the coordination of eye movements. In neurodegenerative diseases, particularly progressive supranuclear palsy (PSP), pretectal involvement contributes to the characteristic vertical gaze palsy and other oculomotor abnormalities.[@bttnerennever2014]
The pretectal complex consists of five distinct nuclei:[@gamlin2006]
The pretectal area occupies the dorsolateral midbrain at the level of the posterior commissure:[@bttnerennever2008]
Pretectal neurons express characteristic molecular markers:[@distler2011]
The pretectal nuclei, particularly the OPN, serve as the central relay for the pupillary light reflex:[@loewenfeld1999]
This bilateral organization explains the consensual pupillary response (both pupils constrict when light is shone in one eye).[@kardon2014]
The nucleus of the optic tract is essential for horizontal optokinetic nystagmus (OKN):[@hoffmann2007]
The pretectal area, particularly connections through the posterior commissure and interstitial nucleus of Cajal, contributes to vertical gaze control:[@horn2008]
PSP prominently affects the pretectal region, contributing to the pathognomonic vertical gaze palsy:[@steele1964]
The vertical gaze palsy in PSP typically begins with downgaze impairment before affecting upgaze. This pattern reflects the preferential vulnerability of downgaze-related neurons in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF) and pretectal connections.[@bhidayasiri2001]
Pretectal involvement in Parkinson's disease produces subtler deficits:[@biousse2004]
Visual processing deficits in [Alzheimer's disease](/diseases/alzheimers-disease) involve pretectal dysfunction:[@scinto1994]
While not a neurodegenerative disease, Parinaud (dorsal midbrain) syndrome illustrates pretectal dysfunction:[@parinaud]
The NOT contains direction-selective neurons that respond preferentially to visual motion in specific directions:[@mustari2008]
OPN neurons exhibit:[@zhang1998]
Assessment of pretectal function includes:[@kawasaki2012]
OKN and vertical gaze assessment:[@leigh2015]
The following diagram shows the key molecular relationships involving Pretectal Nuclei discovered through SciDEX knowledge graph analysis: