[Central representation of the anterior lateral line nerve in dwarf catfish]

The central distribution of the anterior lateral line nerve (ramus) (NLLa) were studied in the pygmean sheat-fish (Ictalurus nebulosus) by means of the method of Nauta--Gygax. NLLa, as well as posterior lateral line nerve (NLLp), projects topographically on the nucleus medialis of the acoustic-lateral area. Within the nucleus medialis NLLa can be traces in the rostro-lateral parts. A majority of NLLa fibres can be followed ipsilaterally, although a definite contralateral contribution also exists. It is concluded that NLLa, representing the electro- and mechanoreceptors of the head region, distributes predominantly within the rostral part of the medial nucleus, while NLLp, representing the trunk receptors, distributes in the caudal half of the medial nucleus. There is some overlapping within the middle part of the nucleus.