BACKGROUND Low doses of local anesthetics applied to the young rat spinal cord in vitro have been shown to inhibit C-fiber-evoked responses. The aim of this work was to investigate whether such low doses applied epidurally selectively reduce nociceptive responses in vivo and to investigate the influence of postnatal development on such local anesthetic actions. METHODS Three groups of rat pup...

Homeostatic regulation is a defining characteristic of sleep but has rarely been examined in infants. This study presents an automated method of sleep deprivation in which 5-day-old rats were shocked whenever the nuchal muscle became atonic. The intensity of shock was always set at the minimal level required to maintain arousal. Deprived pups exhibited rapid increases in sleep pressure, as evid...

The basic scheme of odor perception and signaling from olfactory cilia to the brain is well understood. However, factors that affect olfactory acuity of an animal, the threshold sensitivity to odorants, are less well studied. Using signal sequence trap screening of a mouse olfactory epithelium cDNA library, we identified a novel molecule, Goofy, that is essential for olfactory acuity in mice. G...

Erythromelalgia (EM) is a rare neurovascular disorder characterized by intermittent severe burning pain, erythema, and warmth in the extremities on heat stimuli. To investigate the underlying pathophysiology, peripheral axonal excitability studies were performed and changes with heating and therapy explored. Multiple excitability indices (stimulus-response curve, strength-duration time constant...

In forced-choice detection, incorrect responses are routinely ascribed to internal noise, because experienced psychophysical observers do not act as if they have a sensory threshold, below which all perceived intensities would be identical. To determine whether inexperienced observers have sensory thresholds, we examined psychometric functions (percent correct versus log contrast) for detection...

The molecular mechanisms regulating the sensitivity of sensory circuits to environmental stimuli are poorly understood. We demonstrate here a central role for stem cell factor (SCF) and its receptor, c-Kit, in tuning the responsiveness of sensory neurons to natural stimuli. Mice lacking SCF/c-Kit signaling displayed profound thermal hypoalgesia, attributable to a marked elevation in the thermal...

OBJECTIVE To examine the validity of the PainMatcher in chronic pain. DESIGN Comparison of parallel pain estimates from visual analogue scales with electrical stimulus magnitude matching. PATIENTS Thirty-one patients with chronic musculoskeletal pain. METHODS Twice a day ongoing pain was rated on a standard 100-mm visual analogue scale, and thereafter magnitude matching was performed usin...

Big science is here to stay, but we have yet to make the hard financial and educational choices it imposes. Is There a Sensory Threshold? J. A. Swets. When the effects of the observer's response criterion are isolated, a sensory limitation is not evident.

BACKGROUND AND PURPOSE Sensory evaluation is fundamental to evaluation of patients with Carpal Tunnel Syndrome (CTS). The purpose of this study was to determine the construct validity and responsiveness for sensory threshold tests in patients with CTS. METHODS Sixty-three patients diagnosed with CTS were evaluated prior to orthotic intervention and again at follow up at 6 and 12 weeks. Sensor...

INTRODUCTION A normal sexual response in the female depends on the integrity of afferent sensory input from the genital region. So far genital sensation has been investigated only during a non-excitatory state, and the sensory physiological changes, which occur during the sexual cycle in this region, are still obscured. AIM To investigate the sensory status of the female genital region during...