The concept that cortisolr may be formed by more than one pathway, and pertinent literature leading to this concept, have been discussed previously in reference to the extensive conversion of 17-hydroxypregnenolone to cortisol by slices of a human adrenal cortical tumor (2). Villee et al. (3) demonstrated the conversion of progesterone to 16ac-hydroxyprogesterone (Reaction g, Fig. 1) by homogen...

This study explored the question as to whether hypotension is related to decreased attentional performance and reduced cortical activation. A total of 50 females aged 19-44 years participated in the study. Attentional performance was assessed using three subtests of the Attentional and Cognitive Efficiency (ACE) battery. Contingent negative variation (CNV) as a measure of cortical activation wa...

Previous studies have shown that alpha event-related desynchronization (α-ERD) is associated with reaction to visual stimuli in oddball paradigm, as a reflection of attention allocation and memory updating. The present study tested the hypothesis that it reflects a modality and/or frequency specific mechanism. Electroencephalography (EEG) recordings (64 channels) were performed on 18 healthy su...

Rhythmicity is prevalent in the cortical dynamics of diverse single and multicellular systems. Current models of cortical oscillations focus primarily on cytoskeleton-based feedbacks, but information on signals upstream of the actin cytoskeleton is limited. In addition, inhibitory mechanisms--especially local inhibitory mechanisms, which ensure proper spatial and kinetic controls of activation-...

Experience-dependent plasticity of the adult visual cortex underlies perceptual learning and recovery of function following central nervous system lesions. To reveal the signal transduction cascades involved in adult cortical plasticity, we utilized a model of remapping of cortical topography following binocular retinal lesions. In this model, the lesion projection zone (LPZ) of primary visual ...

1. In freely moving cats, the cortical desynchronization elicited by painless rhythmic distension, or by low voltage electric stimulation, of the small intestine in drowsiness and slow wave sleep is extinguished following a few repetitions. After extinction of the arousal reaction, similar intestinal stimulation was systematically followed by the appearance of synchronized activity, or an incre...

The stability of cortical function depends critically on proper regulation. Under conditions of migraine and stroke a breakdown of transmembrane chemical gradients can spread through cortical tissue. A concomitant component of this emergent spatio-temporal pattern is a depolarization of cells detected as slow voltage variations. The propagation velocity of approximately 3 mm/min indicates a con...

Propagated sensation along the meridian can occur when acupoints are stimulated by acupuncture or electrical impulses. In this study, participants with notable propagated sensation along the dian were given electro-acupuncture at the Jianyu (LI15) acupoint of the large intestine meridian. When participants stated that the sensation reached the back of their hand, regular nervous system action d...

What, if anything, is the functional significance of spatial patterning in cortical feature maps? We ask this question of four major theories of cortical map formation: self-organizing maps, wiring optimization, place coding, and reaction-diffusion. We argue that i) self-organizing maps yield spatial patterning only as a byproduct of efficient mechanisms for developing environmentally appropria...

gorlin-goltz syndrome (ggs) consists of ectodermal and mesodermal abnormalities. in this case report we will investigate lower extremity lesions of ggs. a 52-year-old man with ggs underwent skull and lower extremity computer tomography. radiographic findings included cervical spondylosis, transparent areas with slurred margins, and cerebral falx calcification. tibial and fibular specific cortic...