Time-varied noise effects on color-word test performance

The effects of continuous and time-varied 85 dBA broadband noise on the performance of a Stroop-type color-word test and a related word-reading task were investigated. 10 subjects served in one of three groups receiving either continuous, periodic, or aperiodic noise. All subjects performed in both low noise (65 dBA) and high noise (85 dBA) conditions on 80 trials of both word reading and color naming. Median reaction times in the word-reading task were unaffected by either noise intensity or the time-varied aspects of the noise. However, median reaction times in the color-naming task were significantly elevated in the 85-dBA noise condition. Also, reaction times in the high aperiodic noise condition were significantly elevated relative to the continuous and periodic noise conditions. Results are discussed within the framework of arousal, filter, and information theories.     

The effects of noise on the performance of simultaneous interpreters: accuracy of performance

The effect of noisy listening conditions on the performance of simultaneous interpreters was studied by asking subjects to shadow and simultaneously interpret French prose into English at 3 signal-noise ratios. It was found that while noise had a significant effect on the proportions of texts correctly shadowed and interpreted, there were significantly more errors committed when interpreting than when shadowing at lower signal-noise ratios. This finding, together with analysis of subjects' self-corrections when interpreting, suggested that difficulty in perceiving source language passages reduced the ability of simultaneous interpreters to monitor their interpretations into the target language.     

The effects of ageing and visual noise on conceptual integration during sentence reading

The effortfulness hypothesis implies that difficulty in decoding the surface form, as in the case of age-related sensory limitations or background noise, consumes the attentional resources that are then unavailable for semantic integration in language comprehension. Because ageing is associated with sensory declines, degrading of the surface form by a noisy background can pose an extra challenge for older adults. In two experiments, this hypothesis was tested in a self-paced moving window paradigm in which younger and older readers’ online allocation of attentional resources to surface decoding and semantic integration was measured as they read sentences embedded in varying levels of visual noise. When visual noise was moderate (Experiment 1), resource allocation among young adults was unaffected but older adults allocated more resources to decode the surface form at the cost of resources that would otherwise be available for semantic processing; when visual noise was relatively intense (Experiment 2), both younger and older participants allocated more attention to the surface form and less attention to semantic processing. The decrease in attentional allocation to semantic integration resulted in reduced recall of core ideas in both experiments, suggesting that a less organized semantic representation was constructed in noise. The greater vulnerability of older adults at relatively low levels of noise is consistent with the effortfulness hypothesis.     

The effects of ageing and visual noise on conceptual integration during sentence reading

The effortfulness hypothesis implies that difficulty in decoding the surface form, as in the case of age-related sensory limitations or background noise, consumes the attentional resources that are then unavailable for semantic integration in language comprehension. Because ageing is associated with sensory declines, degrading of the surface form by a noisy background can pose an extra challenge for older adults. In two experiments, this hypothesis was tested in a self-paced moving window paradigm in which younger and older readers' online allocation of attentional resources to surface decoding and semantic integration was measured as they read sentences embedded in varying levels of visual noise. When visual noise was moderate (Experiment 1), resource allocation among young adults was unaffected but older adults allocated more resources to decode the surface form at the cost of resources that would otherwise be available for semantic processing; when visual noise was relatively intense (Experiment 2), both younger and older participants allocated more attention to the surface form and less attention to semantic processing. The decrease in attentional allocation to semantic integration resulted in reduced recall of core ideas in both experiments, suggesting that a less organized semantic representation was constructed in noise. The greater vulnerability of older adults at relatively low levels of noise is consistent with the effortfulness hypothesis.     

Assessing tactile perception: effects of different visual barriers on performance

Blindfolding candidates when testing their tactile performance may increase their anxiety. This study examined whether different visual barriers would influence tactile performance on timed tasks. It was hypothesised that candidates using a blindfold would be more anxious, but that they would benefit by the potentially positive effects of arousal on performance and not differ from candidates using a screen to limit visual access to task material. 200 participants (ages 19 to 30 years), randomly assigned to the two conditions, completed a tactile perception task, as well as an anxiety scale. In contrast to the expected outcome, the screen sample took significantly longer to complete the task. This was hypothesised to be the result of increased distraction given competing cross-modal attentional demands and the consequent visual and tactile attention switching. Practitioners may need to consider the influences of visual interference when assessing tactile performance.     

Comparing the effects of aging and background noise on short-term memory performance

Paired associate recall was tested as a function of serial position for younger and older adults for five word pairs presented aurally in quiet and in noise. In Experiment 1, the addition of noise adversely affected recall in young adults, but only in the early serial positions. Experiments 2 and 3 suggested that the recall of older adults listening to the words in quiet was nearly equivalent to that of younger adults listening in noise. In Experiment 4, we determined the signal-to-noise ratio (S/N) such that, on average, younger and older adults were able to correctly hear the same percentage of words when words were presented one at a time in noise. In Experiment 5, younger adults were tested under this S/N. Compared with older adults from Experiment 3, younger adults in this experiment recalled more words at all serial positions. The results are interpreted as showing that encoding in secondary memory is impaired by aging and noise either as a function of degraded sensory representations, or as a function of reduced processing resources.     

The effects of method of measurement upon children''s performance on visual perceptual tasks

Sixty-four first-grade children of average or above intelligence who did not evidence visual perceptual dysfunction were administered a series of visual perceptual tasks. The tasks evaluated the skills of visual figure-ground perception and form discrimination and involved four methods of measurement of these abilities: tachistoscopic, untimed, naming, and recognition. Results indicated considerable method of measurement influence upon task performance. Implications of the results for both researchers and practitioners are discussed.     

A prospective study of some effects of aircraft noise on cognitive performance in schoolchildren

Before the opening of the new Munich International Airport and the termination of the old airport, children near both sites were recruited into aircraft–noise groups (aircraft noise at present or pending) and control groups with no aircraft noise (closely matched for socioeconomic status). A total of 326 children (mean age 5 10.4 years) took part in three data–collection waves, one before and two after the switch–over of the airports. After the switch, long–term memory and reading were impaired in the noise group at the new airport. and improved in the formerly noise–exposed group at the old airport. Short–term memory also improved in the latter group after the old airport was closed. At the new airport, speech perception was impaired in the newly noise–exposed group. Mediational analyses suggest that poorer reading was not mediated by speech perception, and that impaired recall was in part mediated by reading.     

Some effects of the conditioned suppression paradigm on operant discrimination performance

Three experiments were conducted with rats to determine the effects of electric shock on responding during an operant discrimination. In two of these experiments, a conditioned suppression procedure was superimposed upon a stimulus signalling the availability of food reinforcement (S(D)). Response rates were greatly suppressed, not only in the warning signal periods which preceded each shock, but in the presence of S(D), and the stimulus signalling the unavailability of reinforcement (S(Delta)) as well. A third experiment, in which a very mild shock was used without a warning signal, demonstrated an increased response rate in S(D) and S(Delta), although this effect was rather unsystematic. In a similar study, Hearst (1965) found an increased rate in S(Delta) independent of any change in the S(D) rate. The present study failed to obtain Hearst's effect but illustrated a suppressive effect with a similar procedure.     

Some effects of a model's performance on an observer's electromyographic activity.

It is suggested that motor reactions may be elicited in an observer as a consequence of his exposure to a model and that such reactions may become conditioned to environmental events. An experiment is reported in which observers showed greater EMG activity in the arm while watching models arm wrestle than while watching a model stutter, and greater lip EMG activity while watching a model stutter than while watching arm wrestling. Some evidence for conditioning was found in the arm activity of males watching wrestling.     

The effects of music and task difficulty on performance at a visual vigilance task

Forty subjects performed a visual vigilance task in music or noise and when the task was difficult or easy. Response measures taken were: correct detections, commission errors, detection latencies and d' values. For the difficult version of the task a significant increase in detection latencies was found which music prevented. Broadly similar findings were obtained for correct detections. The results are compared with other studies of detection latency and task difficulty and are discussed in terms of arousal.