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T E Finger

Publications and source records attributed to T E Finger.

84 records · Page 5Linked to original sources
PubMed1980

Nonolfactory sensory pathway to the telencephalon in a teleost fish.

Pathways conveying lateral-line sensory information within the brain of a bullhead catfish terminate in a localized zone within the telencephalon. Thus, the telencephalon in teleosts, as in amniote species, contains regions that receive specific sensory input. Therefore, this lemniscal organization is not restricted to mammalian or amniote species but is a feature common to most, if not all, vertebrates.

Afferent Pathways↗
PubMed1980

Central projections of the frontal organ of Rana pipiens, as demonstrated by the anterograde transport of horseradish peroxidase.

The central projections of the frontal organ of Rana pipiens are more widespread, and more similar to those of the epiphysis, than previously realized. Fibers labeled with horseradish peroxidase were traced to the amygdala, the epiphysis, the pretectal region, and several nuclear areas of the mesencephalic and diencephalic central gray. When peroxidase reaction product was carefully distinguished from neuromelanin by means of polarization microscopy, no unequivocally labeled cell bodies off centrifugal fibers could be found.

Amygdala↗
PubMed1978

Cerebellar afferents in teleost catfish (Ictaluridae).

The cerebellar afferents in the bullhead catfish (Teleostei) were labeled by relying on the retrograde transport of horseradish peroxidase (HRP). Retrogradely labeled neurons were seen in: spinal cord, lateral cuneate nucleus, inferior olive, reticular nuclei, vestibular nuclei, nucleus subeminentialis, n. lateralis valvulae, locus coeruleus, n. mesencephalicus dorsalis, the basal optic nuclei, and a nucleus at the isthmic level which may be equivalent to the pontine nuclei of birds and mammals. Inputs to the molecular layer arise from the inferior olive, locus coeruleus and n. lateralis valvulae in addition to subjacent granule cells. No projections to cerebellum were seen to arise from either the optic tectum or from the inferior lobe. The so-called "lobo-cerebellar" tract in teleosts was reported by Goldstein, amongst many others, who mistook the superior secondary gustatory nucleus for a deep cerebellar nucleus.

Afferent Pathways↗
PubMed1978

Gustatory pathways in the bullhead catfish. II. Facial lobe connections.

The second order projections of the gustatory system in catfish were examined using both retrograde (HRP) and anterograde (degeneration and autoradiographic) hodological methods. Golgi-stained material was used to demonstrate the different cell types in the primary gustatory sensory area, the facial lobe. Efferents from the facial lobe gather into ascending and descending secondary gustatory tracts. The descending tract terminates largely in the medial funicular nucleus and the commissural nucleus of Cajal in the region of the obex. A small portion of the descending tract continues caudally to terminate in the dorsal horn of the spinal cord. The ascending secondary gustatory tract terminates mostly in the ipsilateral superior secondary gustatory nucleus in the isthmic region. A small portion of the ascending tract continues rostrally to terminate in the posterior thalamic nucleus and in the region of the nucleus lobo-bulbaris. Sparser contralateral projections are also seen in the posterior thalamus and isthmic gustatory regions. Three cell types can be discerned in the facial lobe: small, medium and large. The small cells are intrinsic neurons, the medium cells project to the isthmic gustatory nucleus, and the large cells send fibers to the other terminal areas described above, as summarized in figure 19.

Animals↗
PubMed1976

Gustatory pathways in the bullhead catfish. 1. Connections of the anterior ganglion.

The central projections of the external gustatory system in bullhead catfish were examined using orthograde degeneration and retrograde transport of horseradish peroxidase (HRP) techniques. Both large and small cells were observed in the anterior ganglion which contains a mixture of elements from the trigeminal, facial and anterior lateral line nerves. Some of the large cells on the lateral margin of the ganglion were found to belong to the lateral line system. No separation of trigeminal and facial nerve connections could be made. Using HRP, the relation between the barbels and specific ganglion regions was determined. The dorsalmost portion of the ganglion received recurrens nerve inputs (from taste buds on the trunk); the rostromedial portion of the ganglion, from the maxillary and mandibular barbel nerves. The facial lobe (similar to part of the n. solitarius) was found to be divided into lobules by fascicles of nerve fibers. The lateral lobule received input only from the dorsal-most part of the ganglion (recurrens nerve: trunk receptors); the intermediate lobule from the rostro-lateral part of the ganglion (nasal barbel); and the medial lobule from the ventral areas of the ganglion (maxillary and mandibular barbels). Thus a topographical relationship exists between the different taste receptor groups and their locus of representation in the facial lobe. The trunk receptors connect to the lateral lobule; the nasal barbel receptors to the intermediate lobule, and the maxillo-mandibular receptors to the medial lobule.

Afferent Pathways↗
PubMed1975

The distribution of the olfactory tracts in the bullhead catfish, Ictalurus nebulosus.

Using degeneration staining methods, central projections of the olfactory tracts in the bullhead catfish, Ictalurus nebulosus were studied. Seporate lesions were made of the lateral and medial olfactory tracts in an attempt to separate their zones of projection. Three major terminal fields were found: lateral, medial and central-posterior complex. Two additional minor projections were seen: interbulbar and hypothalamic. The lateral division of the olfactory tract terminates in lateral, central and hypothalamic terminal fields. The medial tract projects to lateral, meedial, posterior and hypothalamic fields. All terminal fields were found bilaterally; the lateral tract partly crossing in both the anterior commissure. A small intellbulbar commissure was also found to contain medial tract fibers. Evidence is given to show that the anterior olfactory nucleus, if present in catfish, may be located within the olfactory bulb itself. Similarities between mammalian and teleost olfactory systems are also discussed.

Animals↗