Measurement of the visual attention patterns of people with aphasia: a preliminary investigation of two types of human engagement in photographic images.

The focus of this investigation was to examine the visual attention patterns of adults with aphasia on task-engaged contextualized images in which a human figure was engaged with the context of the image and camera-engaged contextualized images in which a human figure was looking forward toward the camera. Analysis revealed that adults with aphasia tend to fixate rapidly and frequently on human figures in contextualized images regardless of the type of engagement in the image. In addition, they responded to engagement cues when viewing task-engaged contextualized images by fixating more frequently and more rapidly on the object area of interest for these images than for camera-engaged contextualized images.

Accuracy of perceptual and acoustic methods for the detection of inspiratory loci in spontaneous speech.

The present study investigates the accuracy of perceptually and acoustically determined inspiratory loci in spontaneous speech for the purpose of identifying breath groups. Sixteen participants were asked to talk about simple topics in daily life at a comfortable speaking rate and loudness while connected to a pneumotach and audio microphone. The locations of inspiratory loci were determined on the basis of the aerodynamic signal, which served as a reference for loci identified perceptually and acoustically. Signal detection theory was used to evaluate the accuracy of the methods. The results showed that the greatest accuracy in pause detection was achieved (1) perceptually, on the basis of agreement between at least two of three judges, and (2) acoustically, using a pause duration threshold of 300 ms. In general, the perceptually based method was more accurate than was the acoustically based method. Inconsistencies among perceptually determined, acoustically determined, and aerodynamically determined inspiratory loci for spontaneous speech should be weighed in selecting a method of breath group determination.

Accuracy of perceptually based and acoustically based inspiratory loci in reading.

Investigations of speech often involve the identification of inspiratory loci in continuous recordings of speech. The present study investigates the accuracy of perceptually determined and acoustically determined inspiratory loci. While wearing a circumferentially vented mask connected to a pneumotach, 16 participants read two passages. The perceptually determined and acoustically determined inspiratory loci were compared with the actual loci of inspiration, which were determined aerodynamically. The results showed that (1) agreement across all three judges was the most accurate of the approaches considered here for detecting inspiratory loci based on listening; (2) the most accurate pause duration threshold for detecting inspiratory loci was 250 msec; and (3) the perceptually based breath-group determination was more accurate than the acoustically based determination of pause duration. Inconsistencies among perceptually determined, acoustically determined, and aerodynamically determined inspiratory loci are not negligible and, therefore, need to be considered when researchers design experiments on breath groups in speech.