Cortical visual evoked potentials (VEPs) in response to gratings temporally modulated in counterphase were recorded in normal and dark-reared pigmented rats. Temporal modulation was either sinusoidal (0.25-15 Hz, steady state condition) or abrupt (0.5 Hz, transient condition). In normals, the amplitude spectrum of contrast VEPs has two peaks (at about 0.5 and 4 Hz) and a high temporal frequency...

Auditory filter theory dictates a physiological compromise between frequency and temporal resolution of cochlear signal processing. We examined neurophysiological correlates of these spectrotemporal tradeoffs in the human auditory system using auditory evoked brain potentials and psychophysical responses. Temporal resolution was assessed using scalp-recorded auditory brainstem responses (ABRs) ...

We are continually exposed to various visual stimuli in our contemporary society. Temporal frequency characteristics of the neural response to visual stimuli have been reported: Some temporal stimulation frequencies enhance neural responses and these frequencies are harmonically related, with a greatest common divisor frequency of approximately 6.5 Hz. Such stimuli, especially when high in temp...

Auditory filter theory posits a tradeoff in time-frequency analysis: high temporal precision is achievable only at the expense of poorer frequency resolution and vice versa. Here, we examined the hierarchy of brain mechanisms of these spectrotemporal tradeoffs through a series of physiological and behavioral measures aimed to tap temporal and spectral acuity at different levels of the auditory ...

narrative frequency is one of the main temporal and stylistic categories as well as an important miraculous aspect de-familiarizing qur’an. the story of adam is among the qur’anic stories that have been repeated in seven verses. of the artistic aspects of this story, it can be referred to its narrative dissemination. the types of frequency differing from singular, anaphoric, style and anaphoric...

It has been suggested that visual scene recognition is mainly based on spatial frequency (Fourier) analysis of the image. This analysis starts with processing low spatial frequencies (LSF), followed by processing high spatial frequencies (HSF). Within the framework of the spatial frequency analysis, the right/left hemisphere would be predominantly involved in LSF/HSF analysis, respectively. The...

In this paper, using vortex blob method (VBM), turbulent flow in a channel is studied and physical concepts of turbulence are obtained and discussed. At first, time-averaged velocities,  and , and then their fluctuations are calculated. To clarify turbulence structures, velocity fluctuations and  are plotted. It is observed that turbulence structures occupy different positions and move with con...

In the study of verbal memory, a critical question is the extent to which recognition is influenced by the prior contexts in which items have appeared (‘context noise’), as opposed to competition from other items present within the immediate task context (‘item noise’). In a standard recognition task, subjects study a list of words, and at test, discriminate between studied items (targets) and ...

There has recently been much deliberation regarding whether indoor radio communications systems should operate in the 900 MHz band, or in the 1.7 GHz band. However, there are no propagation results available in the literature which compare indoor channel characteristics in the two bands. This paper presents the results of temporally and spatially distributed wideband (impulse response) propagat...