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Biomedical subjects

H L Pick

Publications and source records attributed to H L Pick.

At least 19 recordsLinked to original sources
PubMed1990

The independence of horizontal and vertical dimensions in handwriting with and without vision.

The purpose of this study was to investigate the relationship between horizontal and vertical components of handwriting production when subjects were instructed to vary the size of these components separately or together. The effect of vision on these instructed size transformations also was examined. Eight female adults participated in the experiment. The basic task was to write the words 'poppy' and 'wood' cursively five times, the first time in their normal size and then with four size transformations. These transformations--one-fourth, one-half, double, and four-times their normal size--were made under three different sets of instructions (width only, height only, both) and in two visual conditions (normal, blindfolded), for a total of six sets of five repetitions. The individual slopes (changes in actual values across the transformation values) for width and height under instructions to change both parameters were almost identical to the width and height slopes under instructions to change only the single parameter, supporting the notion of the independence of the horizontal and vertical components. Further, an analysis of these individual slopes indicated that the size transformations were significantly greater (p less than 0.05) (and closer to the instructed values) with vision than without vision.

Adult↗
PubMed1990

Children's use of frames of reference in communication of spatial location.

The frames of reference used by 4-, 6-, and 8-year-old children were studied in a spatial direction-giving task. Children were asked to specify verbally the location of a toy hidden under one of several identical cups. The child and listener sat facing each other at opposite ends of a room that had distinctive or nondistinctive landmarks proximal and distal to the hiding location. Location needed to be specified with respect to either the left-right dimension, the front-back dimension, or both. The results indicated that (1) although children's overall performance improved with age, communication about the left-right dimension was particularly difficult for 4-year-old children and showed a higher rate of improvement with age than communication about the front-back dimension; and (2) the frames of reference that children incorporated into their directions changed with age and differed for directions about the front-back and left-right dimensions. Both 4- and 6-year-old children used person references (themselves or the listener) to specify front-back relations, but only the 6-year-olds were able to compensate for their apparent difficulty in using the terms left and right by using landmarks to specify the left-right dimension. Eight-year-olds used a combination of person and landmark references in directions about both dimensions. Discrepancies between the frames of reference children used to communicate spatial location and those typically used in other spatial cognition tasks are discussed in terms of developmental and task constraints.

Attention↗
PubMed1989

Inhibiting the Lombard effect.

The Lombard effect is the tendency to increase one's vocal intensity in noise. The present study reports three experiments that test the robustness of the Lombard effect when speakers are given instructions and training with visual feedback to help suppress it. The Lombard effect was found to be extremely stable and robust. Instructions alone had little influence on the response to the noise among untrained speakers. When visual feedback correlated with vocal intensity was presented, however, subjects could inhibit the Lombard response. Furthermore, the inhibition remained after the visual feedback was removed. The data are interpreted as indicating that the Lombard response is largely automatic and not ordinarily under volitional control. When subjects do learn to suppress the effect, they seem to do so by changing overall vocal level rather than their specific response to the noise.

Feedback↗
PubMed1978

Intensity of guitar playing as a function of auditory feedback.

Subjects played an electric guitar while auditory feedback was attenuated or amplified at seven sidetone levels varying 10-dB steps around a comfortable listening level. The sidetone signal was presented in quiet (experiment I) and several levels of white noise (experiment II). Subjects compensated for feedback changes, demonstrating a sidetone amplification as well as a Lombard effect. The similarity of these results to those found previously for speech suggests that guitar playing can be a useful analog for the function of auditory feedback in speech production. Unlike previous findings for speech, the sidetone-amplification effect was not potentiated by masking, consistent with a hypothesis that potentiation in speech is attributable to interference with bone conduction caused by the masking noise.

Adult↗
PubMed1976

The influence of selected masking noises on Lombard and sidetone amplification effects.

The present experiments were designed to test the notion that the Lombard and sidetone amplification effects are related to the masking ability of a presented background noise. In Experiment 1, eight normal-hearing college students spoke in quiet and while listening to five frequency bands of noise which were equated for intensity but differed in ability to interfere with speech intelligibility. Vocal intensity increased as the frequency band, and thus the masking ability of the noise increased. In Experiment 2, eight additional students spoke in quiet and while listening to four of the frequency bands of noise used in Experiment 1. The noises were equated for loudness rather than intensity. Again, vocal intensity increased as the masking ability of the noise increased. In Experiment 3, 20 additional students spoke while listening to 0 and 20 dB of sidetone amplification mixed with three of the noise bands from Experiment 1. The noises were equated for intensity and mixed with sidetone. The sidetone amplification effect increased as the masking ability of the noise increased. The results of these experiments indicate that interference with speech intelligibility is directly related to elicitation of the Lombard and sidetone amplification effects. The loudness or intensity of a noise has little control over vocal intensity independent of the contribution to masking of speech.

Auditory Perception↗
PubMed1976

The content and manipulation of cognitive maps in children and adults.

Comparison of cognitive maps generated by first graders, fifth graders, and college students using a triangulation task revealed that the first graders possessed very accurate, coherent cognitive maps. However, analyses of the cognitive maps generated when Ss were asked to imagine either the room rotating (mental rotation) or themselves moving within the room (perspective-taking) revealed that the accuracy and completeness of the mental manipulation increased dramatically with age. Only the cognitive maps of the college students were coherent and accurate during mental rotation than during perspective-taking. Careful attention was given to the types of errors made, and several systematic error patterns were identified which reflected qualitative differences. These qualitative differences indicated mental manipulation was a two-stage process. In the first stage, a strategy of transformation was applied to the ordinal spatial relationships contained within the cognitive map. First graders evidenced difficulty here. In the second stage, more specific relationships between self and spatial layout were reconstructed. Fifth graders evidenced difficulty here. In contrast, college students were able to complete both stages of the process.

Adolescent↗
PubMed1975

Reliability of sidetone amplification effect in vocal intensity.

When the auditory feedback of a speaker's own voice is amplified the speaker reasonably tends to lower his voice. The reliability of this so called sidetone amplification effect was investigated in two experiments. In the first experiment feedback was modulated gradually during a session. In the second experiment the sidetone amplification effect was assessed over five successive days of testing. In both experiments the sidetone effect was very stable despite rather different eliciting conditions.

Feedback↗
PubMed1971

Perception.

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Afterimage↗