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G W Van Hoesen

Publications and source records attributed to G W Van Hoesen.

12 recordsLinked to original sources
PubMed1979

Subicular input from temporal cortex in the rhesus monkey.

The subicular cortices of the primate hippocampal formation form a physical and connectional link between the cortex of the temporal lobe and the hippocampus. Their direct connections with all classes of cortex in the temporal lobe except primary sensory cortex underscore the pivotal role of these areas in the potential interplay between the hippocampal formation and the association cortices.

Amino Acids↗
PubMed1978

Cortico-striate projections in the rhesus monkey: the organization of certain cortico-caudate connections.

The organization of cortical projections to the caudate nucleus was investigated in the rhesus monkey, using the autoradiographic tracing method. Following injections of tritiated leucine and proline into selected pre- and post-Rolandic association areas in the frontal, parietal, occipital and temporal lobes, widespread projections were observed to one, or more typically, more than one of the major subdivisions of the caudate nucleus. When cortical areas having strong reciprocal cortico-cortical connections were compared, a considerable communality of their cortico-caudate projections was noted; depending on the location of the cortical areas, the region of common distribution lay within the head, the body, or the tail of the caudate nucleus. This correlation between cortico-cortical and cortico-striate projections characterized all pairs of cases studied. It suggests a previously undescribed principle of organization within the telencephalon, namely, that areas of cerebral cortex having reciprocal cortico-cortical connections, while having unique overall patterns of projection to the caudate nucleus, project, in part, to one and the same region of the nucleus. This might imply that a given region of the caudate nucleus receives input not only from a particular area of cortex, but also from all other cortical areas reciprocally interconnected with that area.

Animals↗
PubMed1977

Limbic and sensory connections of the inferior parietal lobule (area PG) in the rhesus monkey: a study with a new method for horseradish peroxidase histochemistry.

The caudal part of the inferior parietal lobule (area PG) was injected with horseradish peroxidase (HRP) in 6 hemispheres of 5 rhesus monkeys. The retrograde transport of HRP resulted in the labeling of neurons in diverse cortical and subcortical areas. In cortex, labeled neurons were noted in prefrontal cortex (areas 8, 45, 46), in the banks of the intraparietal and superior temporal sulci, in medial parietal cortex, in cingulate cortex, in the retrosplenial area, in area TF and the caudal portions of the parahippocampal region. Subcortical sites with labeled neurons included the necleus basalis of the substantia innominata, the claustrum, the pulvinar and intralaminar thalamic nuclei, the pretectal area, the nucleus locus coeruleus and the raphe nuclei. Although many of the labeled neurons were seen in layers IIIc and V, each cortical area had an individual laminar pattern of labeled neurons. In these experiments, a benzidine dihydrochloride (BDHC) method was used which yields a blue reaction-product at sites containing HRP. BDHC affords superior visibility of labeled neurons, and a significant improvement in sensitivity when compared to a diaminobenzidine procedure in matching series of sections. Additional sections were also stained with a method which allows the simultaneous demonstration of HRP (blue) and acetylcholinesterase (reddish-brown). These revealed that virtually all substantia innominata (nucleus basalis) neurons which project to area PG are also rich in the enzyme acetycholinesterase. These afferents of PG may be classified into 'sensory association', 'limbic' and 'reticular' categories. It is argued that this arrangement of afferent imput may afford a convergence of limbic and sensory information in area PG and that this may subserve a significant function in the process of sensory attention.

Acetylcholinesterase↗
PubMed1977

Clinical manifestations of chronic thiamine deficiency in rhesus monkey.

In the course of multiple episodes of thiamine deficiency in the rhesus monkey, the triad of anorexia, apathy, and hind limb weakness is the earliest clinical manifestation. In later episodes, nystagmus, abducens paresis, midline ataxia, dysmetria, and congestive heart failure are also seen. With the exception of dysmetria, the neurologic signs promptly respond to thiamine administration. Pair-fed controls showed no clinical signs. Neither peripheral neuropathy nor edema was observed. Thiamine-deficiency in the experimental animals was confirmed by blood transketolase assays.

Abducens Nerve↗
PubMed1976

Temporal neocortical afferent connections to the amygdala in the rhesus monkey.

The temporal neocortical afferent connections to the amygdala were investigated in the rhesus monkey using the silver impregnation and autoradiographic tracing methods. A large topographically organized projection to the amygdala was found to originate from the anterior superior temporal gyrus (area TA), the anterior middle and inferior temporal gyri (area TE), and the medial and lateral aspects of the temporal pole (area TG). These projections terminate in discrete adjacent regions of the lateral and basal amygdaloid nuclei. The temporal pole projection terminates in the ventral two thirds of the medial one half of the lateral nucleus and in the accessory basal nucleus, the anterior superior temporal gyrus projection terminates in the ventral two thirds of the lateral one half of the lateral nucleus, and the anterior middle and inferior temporal gyri projection terminates in the dorsal parts of the lateral and lateral basal nuclei. A projection from the perirhinal cortex to the medial basal nucleus of the amygdala is also discussed. Our findings reveal that a far greater proportion of the temporal neocortex than previously described contributes afferents to the amygdala, further strengthening the view that the amygdala occupies a key anatomical position linking the neocortex with diencephalic structures.

Afferent Pathways↗
PubMed1975

Some connections of the entorhinal (area 28) and perirhinal (area 35) cortices of the rhesus monkey. III. Efferent connections.

In this investigation the efferent projections of the entorhinal and prorhinal cortices relative to their sites of termination in the hippocampus and fascia dentata were investigated in the rhesus monkey using experimental silver impregnation methods. Contrary to the often cited observations of Lorente de No, all entorhinal areas, including the laterally lying prorhinal cortex, were found to give rise to the perforant pathway, and furthermore, each cytoarchitectonically defined subarea was found to contribute a unique component. These perforant pathway components terminate in distinct regions of the dendritic zones of the fascia dentata granule cell and the hippocampal pyramidal cell. A previously undescribed projection to the prosubiculum and hippocampus has been found to originate from the prorhinal cortex which forms the medial wall of the rhinal sulcus along the lateral-most portion of the entorhinal cortex in the rhesus monkey. These results, in conjunction with our previous observations regarding differential afferents to the entorhinal cortex, indicate that specific afferent and efferent connections characterize each cytoarchitectonically definable subareas of this periallocortical region. Additionally, they indicate that the perforant pathway might be conceptualized as the final link in a multisynaptic series of connections instrumental in providing the hippocampus with potential modality specific and multimodal input.

Animals↗