This study bears on the projections of layer 5 cells of the vibrissal sensory cortex to the somatosensory thalamus in rats. Small groups of cells were labeled with biotinylated dextran amine (BDA), and their axonal arborizations were individually reconstructed from horizontal sections counterstained for cytochrome oxidase. Results show that the vast majority ( approximately 95%) of layer 5 axon...

Functional magnetic resonance imaging (fMRI) of the hand representation in primary somatosensory cortex (area 3b) of macaque monkeys revealed an ipsilateral hand input undetected by most previous studies. Ipsilateral responses had a hemodynamic signature indistinguishable from that of contralateral hand responses. We explored the neural mechanisms of the fMRI effects using a second derivative a...

Background Researchers have recently begun to seek cognitive explanations for physical symptoms with no obvious biological cause. Concepts such as somatization, somatosensory amplification, and somatosensory catastrophizing have been invoked to explain these phenomena. Somatosensory amplification occurs when these bodily sensations become stronger and more painful. Somatosensory catastrophizing...

To elucidate the dental pulp-representing area in the human primary somatosensory cortex and the presence of A-beta fibers in dental pulp, we recorded somatosensory-evoked magnetic fields from the cortex in seven healthy persons using magnetoencephalography. Following non-painful electrical stimulation of the right maxillary first premolar dental pulp, short latency (27 ms) cortical responses o...

BACKGROUND Reflexology is an alternative medical practice that produces beneficial effects by applying pressure to specific reflex areas. Our previous study suggested that reflexological stimulation induced cortical activation in somatosensory cortex corresponding to the stimulated reflex area; however, we could not rule out the possibility of a placebo effect resulting from instructions given ...

Injections of tritiated amino acid into the pretectothalamic border area of cats resulted in the appearance of numerous silver grains in the ipsilateral claustrum. The accumulation of grains was especially abundant in the dorsomedial area of the central part of the claustrum. These results indicate the presence of substantial projection from the pretectothalamic border area to the claustrum. It...

The prefrontal cortex (PFC) receives input from sensory neocortical regions and sends projections to the basal forebrain (BF). The present study tested the possibility that pathways from sensory cortical regions via the PFC-BF and from the BF back to specific sensory cortical areas could modulate sensory responses. Two prefrontal areas that responded to stimulation of the primary somatosensory ...

The efferent cortico-cortical projections of the motorcortical larynx area were studied in three rhesus monkeys (Macaca mulatta), using biotin dextranamine as anterograde tracer. Identification of the larynx area was made with the help of electrical brain stimulation and indirect laryngoscopy. Heavy projections were found into the surrounding ventral and dorsal premotor cortex (areas 6V and D),...