Decussation Of Brachium Conjunctivum


BACKGROUND: Caudal midbrain lesions involving the entire decussation of the superior cerebellar peduncles have a distinctive clinical picture: bilateral cerebellar ataxia, eye-movement disorders, and palatal myoclonus. OBJECTIVE: To define the clinical and radiologic picture of patients with unilateral lower midbrain ischemic lesions of the decussation of the brachium conjunctivum.  

Ipsilateral involvement of both cerebellofugal fibers, before and after decussation, was responsible for bilateral cerebellar ataxia..  

the habenulo-interpeduncular tract, decussation of the dorsal tegmentum, the medial longitudinal fasciculus, transverse pontine fibers, the brachium conjunctivum and the inferior cerebellar peduncle were cadherin-8 positive, as were the spinal tract of the trigeminal nerve, oculomotor nerve, facial nerve and trigeminal nerve.  

Retrograde labelling from LPO was found in the archistriatum, dorsomedial thalamic complex, nuclei lateralis anterior and superficialis parvicellularis thalami, substantia nigra, central gray, area ventralis tegmentalis of Tsai, and locus coeruleus and in cells dorsal to the decussation of brachium conjunctivum.  

Stimulation of a region of slices presumably corresponding to the decussation of brachium conjunctivum evoked mainly monosynaptic EPSPs with a "fast"-rise time in the RN neurons, which suggests activation of the synaptic input from the cerebellar nucleus interpositus.  

At all ages, the main ascending limb of the BC can be followed from its emergence, dorsal to the cerebellar plate where it assumes an almost vertical course, up to its decussation. In E16 and E17 embryos, labeled BC fibers extend beyond the decussation in the caudal part of the red nucleus.  

In contrast to the current concept of abortive regeneration of mammalian central axons, the occurrence of marked, functionally active, regeneration of the cerebellofugal projection was proved in the cat after complete transection of the decussation of the brachium conjunctivum (BCX).  

In contrast to the current concept of abortive regeneration of mammalian central axons, occurrence of marked, functionally active regeneration of the cerebellofugal projection was proved in kittens after complete transection of the decussation of the brachium conjunctivum (BCX).  

This finding, together with a reexamination of data from two related studies from this laboratory strongly support the conclusion that an essential premotor component of the conditioned NM response is a doubly decussating circuit from the interpositus nucleus of the cerebellum to magnocellular red nucleus, via brachium conjunctivum and its decussation, and from red nucleus caudally, via the ventral tegmental bundle and the rubrobulbar tract, to the accessory abducens nucleus, where motoneurons involved in the NM response are located.  

Besides DA cells of SN and its extensions, DA cells were also observed more caudally in nucleus raphe linearis intermedius and dorsalis, decussation of brachium conjunctivum, fasciculus longitudinalis medialis and periaqueductal gray.  

Type A, B and C neurones were found intermingled, around the brachium conjunctivum and among its fibres from the level of the decussation to the posterior end of the locus coeruleus complex.(ABSTRACT TRUNCATED AT 400 WORDS).  

Rostro-caudally, silver grain accumulation within the LPRF extends from the level of the motor trigeminal nucleus (VM) to the pyramidal decussation, exhibiting a cephalocaudal decrease of grain density.  

Using the paired sample method for comparing data cube by cube in the two conditions it was shown that under pentobarbitone, RRU activity was profoundly depressed in the reticular formation surrounding dorsal and ventral bulbar respiratory nuclei, in the region bridging the gap between these and the pneumotaxic centre and extending from the pneumotaxic level to the decussation of the brachium conjunctivum.  

The contralateral descending pathway (B.C.de) roceeds caudally from the decussation of the B.C.  


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