The voice range profile (VRP) is a display of vocal intensity range versus fundamental frequency (F0). Past measurements have shown that the intensity range is reduced at the extremes of the F0 range, that there is a gradual upward tilt of the high- and low-intensity boundaries with increasing F0, and ...

The effects of acute administration of the opioid compounds buprenorphine, morphine, and naloxone were studied on auditory and visual threshold functions and reaction time performances in baboons. Baboons were trained in a reaction time procedure to hold a lever depressed, and release the lever when a signal was presented. Auditory ...

Three monaural chinchillas were trained to detect intensity decrements in broadband noise (20 kHz) using a shock-avoidance conditioning procedure. The intensity decrements were presented at one of nine different durations between 2 and 35 ms at noise levels of 25, 45, and 65 dB SPL. At each intensity-duration combination, the ...

A response to light in an adult monogenean is reported for the first time. Living encotyllabine (capsalid) monogeneans, identified tentatively as Encotyllable caballeroi Velasquez, 1977, attached to pharyngeal tooth pads excised from two species of teleost fish, contracted rapidly when the intensity of the incident illumination was suddenly increased. Contracted ...

The effects on retinal and cortical visual evoked phenomena of the stimulus intensity/spatial frequency and of the spontaneous, physiological blood glucose/ammonia fluctuations were investigated comparatively in a pilot study on young male volunteers. Flash ERG and flash OPs to 5 different stimulus intensities and pattern VECP to 3 spatial frequencies ...

Silent (LPa2 and LPa3) and spontaneously active (V3, V5, V17) neurons of subesophageal ganglia of Helix pomatia were irradiated via a 125-mm fiber probe with a 10-mW He-Ne laser (lambda = 632.8 nm), and the rate of membrane depolarization, duration of latent period, and probability of spike activity were measured ...

Under anesthesia peak latencies occurring up to 75 milliseconds after stimulus onset upon somatosensory evoked potential testing of the somatosensory evoked potential testing of the posterior tibial nerve were not affected by stimulus intensity (between 5 and 19 ma) or by length of time under isoflurane and nitrous oxide up ...

Air-puff stimuli were applied to the skin of the face to obtain psychophysical and neurophysiological responses. Six levels of stimulus intensity above threshold were adopted for numerical magnitude estimation and for recording somatosensory evoked potentials (SEPs). A power function with an exponent of 0.71 provided an adequate description of the ...

Wavelength discrimination was measured in 8 normal observers as a function of test field intensity (2.5-63 td), duration (0.5-5 sec) and dia (0.5-2 degrees) to determine the conditions under which the just noticeable difference (JND) is smallest. The wavelengths of the standard and comparison hemifields were always equated for the ...

A multilayer system of alternating high and low nonlinear materials can be designed to respond actively to the radiation intensity, whereby it transmits ambient light but rejects high-intensity light over a broad spectral region. The transmission of the low-intensity light is determined by the linear refractive indices of the multi-layer ...

Although it is well known that patients with mild head injury (MHI) are less able to endure intense light and sound stimuli than normal people, there are few psychophysical studies that have objectively measured this type of hyperaesthesia. In the present study, using a computerised rating scale technique, both the ...

An analysis of a population response recorded from the primary afferents was undertaken to study the neural signs of intensity coding in the peripheral somatosensory system. Short air-puff stimuli were applied to the volar aspect of the tip of the index finger to obtain both neural and psychophysical responses. The ...

Four experiments were conducted to investigate the acoustic startle response to stimuli of low intensities. Eyeblink responses (integrated EMG from orbicularis oculi) were measured from male and female college students. Experiment 1 compared tone and noise stimuli varying in intensity (50 and 60 dB(A) SPL), with noise stimuli producing greater ...

This study examined the pattern of intensity integration at threshold. The stimuli studied are unique in that they have a compound peak-to-peak amplitude envelope. This waveform was partitioned into two segments, each having a different peak-to-peak magnitude (bi-amplitude). All signals in the bi-amplitude series were the same duration (100 ms). ...

Time-resolved X-ray equatorial diffraction studies on a single frog skeletal muscle fiber were performed with a 10 ms time resolution using synchrotron radiation in order to compare the time courses of the molecular changes of contractile proteins and the intracellular Ca2+ transient during an isometric twitch contraction at 2.7 degrees ...

Various models for sensory coding have used statistical approaches based on the assumption that the stimulus intensity parameter is represented in the afferent neurons as mean firing frequency. In this paper we question the assumption that this is the only code for intensity. We show that in lobster olfactory receptors ...

Effects of stimulus context on magnitude estimations and on category ratings were examined for a range of stimulus intensities of a 1-kHz tone. The stimuli were distributed in equal-interval steps of energy so they formed a perceptual cluster of high-intensity tones with a perceptual outlier at the lowest intensity. According ...

The flash-evoked potential (FEP) of rats has a large negative peak (N160) approximately 160 ms following stimulation. This peak has been reported to be modulated by the subject's state of behavioral arousal and influenced by several test parameters. These experiments examined the influences of repeated testing, the number of stimuli/session, ...

We attempted to demonstrate that significant perceptual stimuli would induce different degrees of heart rate deceleration depending on when (phase) in the cardiac cycle they occurred. Relative to previous work, we concurrently examined a number of factors that might alter the amplitude of such a cardiac cycle time effect. Stimulus ...

Click intensity effect (90 to 0 dB HL) on amplitude of the auditory brainstem responses (ABAR) was studied in 152 normal children from birth to 6 years and 16 adults. All age groups showed similar amplitude-intensity functions for waves I and V. Wave I amplitude exhibited a 'transitional' response at ...

Efficient and accurate computation of the scattered intensity pattern by the Mie formulas is now feasible for size parameters up to x = 50,000 at least, which in visual light means spherical drops with diameters up to 6 mm. We present a method for evaluating the Mie coefficients from the ...

We studied the effect of various background intensities on the components of fluctuation by testing 20 healthy subjects on the Humphrey Field Analyzer. Our results show little difference in the total fluctuation between two low photopic background intensities similar to those commonly used on commercial perimeters: 3.02 dB for 31.5 ...

This study evaluated frequency discrimination ability in 11 monkeys over an extended period of time using a repeating-standard procedure and the method of constant stimuli. The intersubject variability of the difference limens for frequency (delta F) was large, as reported by other investigators, but similar in magnitude to the variability ...

Intense hurricanes occurred much more frequently during the period spanning the late 1940s through the late 1960s than during the 1970s and 1980s, except for 1988 and 1989. Seasonal and multidecadal variations of intense hurricane activity are closely linked to seasonal and multidecadal variations of summer rainfall amounts in the ...

Rate-intensity functions at characteristic frequency (CF) were recorded from single fibres in the auditory nerve of anaesthetised guinea pigs. Within the same animal, CF rate-intensity functions, although probably forming a continuum, could be conveniently divided into three groups; (1) Saturating; reach maximum discharge rate within 30 dB of threshold, (2) ...

In a previous paper (Winter et al., 1990) we demonstrated the existence of a new type of auditory-nerve rate-intensity function, the straight type, as well as a correlation between rate-level type, threshold and spontaneous rate. In this paper we now show that the variation in rate-intensity functions has its origin ...

An ultrasonic stimulus induced negative phonotactic steering in the yaw axis of tethered, flying Australian field crickets. The forewings, hindwings and twisting of the thorax generated the forces which induced the yaw turn. However, abdominal ruddering did not contribute to yaw turns. Each aspect of the yaw steering response depended ...

Measurements of Open Quotient (OQ) and Speed Quotient (SQ) were made from photoglottographic signals of normal male subjects during phonation. Samples were obtained at spontaneous levels of fundamental frequency and intensity, and at nine specified frequency/intensity combinations. OQ increased with fundamental frequency. OQ change was not significant for change in ...

Loudness functions and their associated neural-count functions are derived for steady-state tones at 250 and 1000 Hz from measurements of intensity discrimination obtained under gated and continuous conditions. The calculations are based on a multichannel generalization of the McGill-Goldberg counting model [J. Acoust. Soc. Am. 44, 576-581 (1968)]. Using the ...

Auditory brain stem responses (ABR) were recorded from the head surface of non-anesthetized and non-relaxed bottle-nosed dolphins, Tursiops truncatus. The region of best ABR recording was shown to be located 6-9 cm caudal to the blowhole. The threshold values were about 1 mPa for noise bursts and -3 dB re ...

A laser beam touching the periphery of a polished cylinder is subjected to both diffraction and reflection. In the area where diffracted light and reflected light interact the resulting intensity distribution differs from the pattern predicted by diffraction theory for a sharp edge. The difference increases with cylinder radius. In ...

Subjects judged the odor intensity of single odorants and binary mixtures of fixed or varying proportions presented in the atmosphere of an environmental chamber. The subjects were exposed to the vapors either continuously (15 min) or periodically (once a minute for 15 min). As found previously, the mixtures smelled less ...

In the literature two different views with regard to the time course of activation of "recognition units"--hypothetical entities that represent identity information--are proposed. Both views are derived from a restricted set of phenomena in visual perception. The first view gets its intuitions from phenomena such as those summarized by Bloch's ...

Spatial distribution of coherent light intensity is measured with an acoustooptic Bragg cell. With step function or short pulse driving signals, the integral function of the spatial intensity distribution or the distribution itself appears at the time dependent output of a single detector. Speed, resolution, and dynamic range are comparable ...

Evaluates 2 theoretical models suggested to explain studies of the effect of stimulus intensity on the perceived duration of brief light flashes. Some studies found a direct relationship between the 2 variables; others found an indirect relationship. Each model suggests that an additional variable interacts with stimulus intensity. Proposed variables ...

Auditory middle latency responses (MLR) and auditory brainstem responses (ABR) were measured with epidural electrodes in unanesthetized gerbils. Response thresholds of simultaneously recorded MLRs and ABRs, and latencies and amplitudes of MLR peaks were analyzed with respect to stimulus intensity (10-80 dB SPL) and frequency (0.5, 1, 2, 4, 8 ...

In each of two trials a 2 x 2 factorial arrangement of treatments was used to evaluate the growth response of tom turkeys to environmental light. The main experimental light treatment factors were: daylength [23 h light (L):1 h dark (D) vs. 8 h L:16 h D] and light intensity ...

Short-term memory for brief electrical stimulation of rats' ventral tegmentum was assessed in a delayed conditional discrimination procedure in which trials began with a train of either low- or high-intensity stimulations. After a delay (i.e., retention interval) ranging from 0.01 to 4 sec, a lever was inserted, accompanied by a ...

Simple unimanual reaction times to lateralized light flashes were measured in 40 normal subjects, 4 commissurotomized patients, and a boy with callosal agenesis. In all subjects, reaction times tended to be shorter when the stimuli were presented on the same side as the response hand (uncrossed condition) than on the ...

The present study was designed to test whether human auditory brain-stem responses (ABRs) are sensitive to peripheral endocrine signals as reflected by changes in the plasma glucocorticoid concentration. ABRs were recorded following treatment with 50 mg hydrocortisone or placebo in 13 healthy male adults. Experiments were double-blind and designed according ...

The 2-deoxyglucose (2-DG) autoradiographic technique was employed to map activation of the central auditory pathway in the mongolian gerbil during stimulation with a 3.0 kHz tone at several intensities. In most auditory nuclei, the tone produced restricted areas in which 2-DG uptake was markedly higher than that of adjacent tissue, ...

The theoretical model for perceived intensity in human taste and smell published previously was extended by incorporating the concept of signal detectability and temporal integration phenomena at low and high stimulus levels. The processes involved in human taste and smell perception are divided into three stages: a) An "internal meter" ...

A model description of intensity perception in human taste and smell developed earlier has now been verified experimentally to determine parameter values for odorants. The final objective is to quantify and understand odour-odour interaction phenomena in e.g., masking, deo-perfumes and flavour enhancement. Five types of olfactometer experiments were carried out, ...

Experiments, involving sequential micro-stimulation of two (or more) adjacent neuroommatidia in the compound eye of the blowfly,Calliphora erythrocephala (Mg.), are presented. These experiments, using brief flashes of 3 ms duration with low intensities in the order of 8.10(-3) Cd/m(2), are performed to isolate individual response contributions of single Elementary Movement ...

The relationship between auditory evoked potentials (AEP) and the German version of Zuckerman's Sensation Seeking Scale was examined. The slope of the amplitude/stimulus intensity function (N1/P2 component) and the N1 latency were particularly studied, as these variables have been found to be potential predictors of the response to lithium prophylaxis. ...

Intensity discrimination thresholds for 500-ms pure-tone bursts were measured as a function of frequency in the goldfish (Carassius auratus) using classical respiratory conditioning. At 55-dB sensation level (SL), thresholds range from 1.44-2.2 dB between 100 and 1600 Hz. There is not important effect of frequency on intensity discrimination. Thresholds at ...

The influence of the intensity of passively perceived 1-kHz tones on the latencies and amplitudes of AEP components in the 80- to 200-ms latency range recorded from frontal, central and temporal electrode locations was investigated in healthy adult subjects. At stimulus intensities from 30 to 70 dB SL the latencies ...

The ability of goldfish to detect a change in the frequency of 400-Hz pure-tone bursts was studied using classical respiratory conditioning. The frequency discrimination threshold was measured at 15-, 35-, and 55-dB sensation level (SL), under conditions of (1) constant intensity, (2) roving intensity (plus and minus 6-dB burst-to-burst variation ...

We have measured the spectral properties of the fourth anti-Stokes component of the output of a pressurized, molecular hydrogen, Raman shifter pumped by the intense output of a frequency-doubled narrowband pulsed dye laser. All the observed line shapes are asymmetric, with full widths at half-maximum ranging from 0.3 to 0.8 ...

Low levels of visible light directed onto slices of rat cerebral cortical tissue enhanced net potassium-induced release of the neurotransmitter gamma-aminobutyric acid (GABA) from these brain slices. At higher light intensity, net potassium-induced release was suppressed. These effects were apparently not from increased temperature. The amount of light enhancing this ...