Contrast-modulated (CM) gratings, composed of two luminance-modulated sinusoids of similar spatial frequency, mask the detection of test sinusoids at the difference frequency. However, the mechanism underlying masking by CM gratings remains poorly understood. In this paper, we aimed to determine whether the masking of 1 cycle deg(-1) LM test gratings by a 1 cycle deg(-1) beat (formed from a pai...

E ective Human-to-Human communication involves both auditory and visual modalities, providing robustness and naturalness in realistic communication situations. Recent e orts at our lab are aimed at providing such multimodal capabilities for humanmachine communication. Most of the visual modalities require a stable image of a speaker's face. In this paper we propose a connectionist face tracker ...

An evaluation of the reliability of the ITU-T P.85 recommended standard for the evaluation of voice output systems was conducted using six English TTS systems. The P.85 standard is based on mean-opinion-score judgements of a listening panel on a number of rating scales. The study looked at how the ranking of the six systems on the scales varied across four different text genres and across two l...

One of the most important features of conversational speech is its variability. Two different speakers utter the same word very differently. Even the same word uttered by the same speaker twice, will not be identical. We also know that even small changes in the speech signal can hamper speech perception processes drastically. A simple change of segments can lead to problems for listeners identi...

From a contact theory perspective, links between variation in young adults’ perceptions of communication with their grandparents and attitudes towards older adults are examined. The analysis pays particular attention to variation in communication with multiple grandparents, and finds links between that and perceived variability in the older adult population as a whole. More variation in percept...

The two-stage decomposition-recombination model of 2D motion perception has been criticised on the basis that the direction of plaid stimuli can be accurately discriminated at speeds so low that the direction of their Fourier components is not discriminable. The nature of this gap in performance between gratings and plaids was investigated across a range of spatial frequencies and durations for...

We measured thresholds for the perception of blue under chromatic adaptation to white, green, yellow or red at the eccentricities of 0-70 deg in the temporal visual field of four subjects. We used a series of stimulus sizes at each eccentricity, without a prior assumption of any peripheral size-scaling factor. The CIE 1976 UCS (u',v') chromaticity coordinates corresponding to blue perception we...

We investigated the relations among mental rotations and spatial perception abilities, handedness, and sexual orientation in both men and women. The present study included a relatively large sample and attempted to control statistically for important covariates such as general intelligence. Significant sex differences were obtained for mental rotations and spatial perception, but not for handed...

Visual attention affects both perception and neuronal responses. Whether the same neuronal mechanisms mediate spatial attention, which improves perception of attended locations, and nonspatial forms of attention has been a subject of considerable debate. Spatial and feature attention have similar effects on individual neurons. Because visual cortex is retinotopically organized, however, spatial...