Listening to discourse in distracting settings: the effects of aging

Younger and older adults listened to discourse in quiet and in conversational noise, before answering questions concerning the material. Some questions required listeners to recall specific details; others were of a more integrative nature. When the listening situation was adjusted for individual differences in hearing, younger and older adults were equally adept at remembering the gist of the passages in both quiet and in two levels of noise. The two age groups also did not differ with respect to memory for specific details when listening in quiet or in a moderate level of noise, even when required to perform a concurrent task. Only at the loudest noise level did younger adults tend to recall more detail than older adults. However, when no adjustments were made to compensate for the poorer hearing of older adults (all participants tested under identical listening conditions), older adults could not recall as much detail as younger adults, either in quiet or in noise. The results indicate that the speech-comprehension difficulties of older adults primarily reflect declines in hearing rather than in cognitive ability.     

Effects and aftereffects of continuous noise and computation work on risk and effort choices

Choices between risk and effort, in a format (COPE) previously shown to reflect fatigue, were obtained from subjects in noise or quiet. Both sexes were used in the experiment, half the subjects working at the Norinder arithmetic task while half rested. The COPE test took a computational form, offering choices between digit lists of differing lengths in which target sums were imbedded. The baseline choice levels were established in quiet, but half the subjects were exposed to noise during the posttest. As previously found in comparable conditions, the Norinder task showed no effect of noise. Pretest-posttest comparisons on the COPE test showed that exposure to noise, like computation work, had the predicted effect of decreasing the choice of high-probability, high-effort alternatives. The presence of noise during posttest had no overall effect on risk effort choices, although there were indications that changes of any kind in the test conditions might be a factor. The data seem difficult to explain in an arousal framework, but may be simply interpreted as showing that exposure to noise produces real fatigue.     

Index to Volume 117

In some individuals, noise appears to have an adverse effect on memory recall. This decrement may result from a shift in the memory strategy being employed. Studies have shown memory strategies used by persons with an internal locus of control differ from those used by persons with an external locus of control. The present investigation asked subjects who were classified as either internal or external in locus of control to recall words presented under conditions of noise and of quiet. Word recall was aided by providing subjects with potential memory strategies. Each word list included words from meaningful content categories (which favor a semantic strategy) and word pairs that rhymed (which favor a perceptual strategy). Though internal and external subjects did not differ in total words recalled, they did differ in their use of strategies. Whereas internal subjects' strategies were unaffected by noise, external subjects decreased their use of the higher level semantic memory strategy (content categories) and increased their use of lower level perpetual (rhymes) strategy in the noise condition. The results are discussed in terms of a differential arousal hypothesis.     

Noise effects on rehearsal rate in short term serial order memory

Three experiments are reported which were designed to test the hypothesis that the rate of rehearsal during noise is slower than that under quiet conditions. The first experiment measured directly the rate of articulation while subjects either read or rehearsed a set of five consonants. It was shown that while the rate of articulation when reading aloud did not differ under the two noise levels [65 dB(C) and 85 dB(C)], rate of articulation during overt rehearsal in loud noise was significantly slower than under quiet conditions. In Experiment II a similar effect was demonstrated where words were required to be read or rehearsed; here it was shown that the greatest impairment due to noise was on the rate of rehearsal of words of long spoken length.

The third experiment showed that loud noise impaired recall performance more markedly for a set of words of long spoken length presented early on in the sequence than for a set of shorter words, even though both sets were equal in the number of syllables and phonemes they contained.

It was concluded that in verbal memory tasks where rote rehearsal of the to-be-remembered material is the predominant strategy for enhancing trace duration, noise may affect memory performance by slowing down the rehearsal rate.     

Auditory discrimination in conditions of noise and quiet by black and white disadvantaged children.

The auditory discrimination of first and third grade children of low socio-economic status was investigated. 17 black and 17 white children were randomly selected from the two grades. The condition for listening was varied, i.e., discrimination in condition of quiet and discrimination in condition of noise, through the use of the Goldman-Fristoe-Woodcock Test of Auditory Discrimination. White third graders were superior performers. The expectation, from the literature, that the auditory discrimination of children from low socio-economic levels would be depressed in conditions of noise was not supported. In fact, black children performed in an inferior manner in conditions of quiet.     

Effects of jet engine noise and performance feedback on perceived workload in a monitoring task

This study examined the effects of exposure to intermittent jet aircraft noise (70 dBA or 95 dBA maximum intensity) and knowledge of results concerning signal detections (hit-KR) on performance efficiency and perceived workload in a 40-min visual vigilance task. The noise featured a Doppler-like quality in which planes seemed to approach from the monitor's left and recede to the right. Perceptual sensitivity (d') was poorer in the context of noise than in quiet but only in the presence of hit-KR. The lack of noise-related performance differences in the absence of hit-KR most likely reflected a "floor effect" rather than some special relation between noise and feedback. When compared to subjects performing in quiet, those who operated in noise were less able to profit from hit-KR, a result that may reflect the effects of noise on information processing. In addition to its negative effects on signal detectability, noise elevated the perceived workload, as measured by the NASA-TLX. This effect was robust; it was independent of the presence of hit-KR, even though hit-KR generally lowered the overall level of perceived workload. The results provide the initial experimental demonstration that perceived workload is a sensitive measure of the effects of aircraft noise in monitoring tasks.     

The effects of noise on recall of lists of associated words

An experiment investigated the effect of noise on recall of lists consisting of pairs of strong and weak associates. Noise improved recall (both number recalled and organization of recall) and did so with both types of list. The subjects who were initially tested in noise continued to show better recall and organization of recall even when they were transferred to the quiet condition. This finding shows that noise may reinforce the use of the dominant strategy and that this strategy may be used more in noise when experimental conditions are changed and even when the subject is transferred from the noise to the quiet. This research was supported by a grant from the Social Science Research Council.     

Gender Differences in Biobehavioral Aftereffects of Stress on Eating,Frustration, and Cardiovascular Responses1

Eating, persistence, and cardiovascular responses were evaluated after exposure to a 25‐min noise stressor with or without perceived control. Participants were healthy men (n = 29) and women (n = 34), aged 21 to 45 years. There were no group differences in cognitive task performance or blood pressure during the stressor. However, perceived control resulted in lower mean blood pressure and heart rate after cessation of the stressor for men and women. Women without perceived control displayed greater frustration levels following the stressor, and frustrated women ate more bland food than did nonfrustrated women. Perceived control and frustration did not affect food consumption among men following the stressor. These findings indicate that there are health‐relevant gender differences in biobehavioral responses that occur in the aftermath of stressor exposure. In addition, perceived control was especially important for women to attenuate the behavioral and biological effects of stressor exposure.     

CHRONIC NOISE AND PSYCHOLOGICAL STRESS

Abstract— This article illustrates the value of incorporating psychological principles into the environmental sciences Psycho physiological, cognitive, motivational, and affective indices of chronically exposed to aircraft noise We demonstrate for the first time that chronic noise exposure is associated with elevated neuroendocnne and cardiovascular measures, muted cardiovascular reactivity to a task presented under acute noise, deficits in a standardized reading test administered under quiet conditions, poorer long-term memory, and diminished quality of life on a standardized index Children in high-noise areas also showed evidence of poor persistence on challenging tasks and ambulation to auditory distraction on a signal-to-noise task They reported considerable annoyance with community noise levels, as measured utilizing a calibration procedure that adjusts for individual differences in rating criteria for annoyance judgments     

The perception of control in loud noise

Perception of control is known to affect performance under stress. Two experiments are reported the object of which was to find out how loud noise during a contingency assessment task influences perceived control. Subjects were required to choose one of two responses, note one of two results, and then provide an overall percentage estimation of the degree of contingency present after 40 trials. Subjects made these judgments for one of three levels of objective contingency (25%, 50%, 75%), either in quiet (55 dBA) or in loud noise (95 dBA) conditions. The first experiment involved a series of randomly chosen, preprogrammed outcomes for noncontingent trials. An unexpected effect of noise was that subjects improved their successes in predicting events, and could only have done so by finding sequential structure in the preprogrammed alternations. They also overestimated control relative to contingency data actually received, at the 25% objective contingency level, but the result could have been dependent on different base levels of data actually received. A second experiment, with a random generation of outcomes for noncontingent trials, resulted in no differences in success levels, but confirmed that noise is associated with the overestimation of contingency at the 25% objective contingency level and demonstrated the same effect for the 50% level. The results are discussed in the context of the 'illusion of control'.     

Auditory apparent motion under binaural and monaural listening conditions

This investigation examined the ability of listeners to perceive apparent motion under binaural and monaural listening conditions. Fifty-millisecond broadband noise sources were presented through two speakers separated in space by either 10 degrees, 40 degrees, or 160 degrees, centered about the subject's midline. On each trial, the sources were temporally separated by 1 of 12 interstimulus onset intervals (ISOIs). Six listeners were asked to place their experience of these sounds into one of five categories (single sound, simultaneous sounds, continuous motion, broken motion, or successive sounds), and to indicate either the proper temporal sequence of presentation or the direction of motion, depending on whether or not motion was perceived. Each listener was tested at all spatial separations under binaural and monaural listening conditions. Motion was perceived in the binaural listening condition at all spatial separations tested for ISOIs between 20 and 130 msec. In the monaural listening condition, motion was reliably heard by all subjects at 10 degrees and 40 degrees for the same range of ISOIs. At 160 degrees, only 3 of the 6 subjects consistently reported motion. However, when motion was perceived in the monaural condition, the direction of motion could not be determined.     

Structural equation models of memory performance across noise conditions and age groups

Competing models of declarative memory were tested with structural equation models to analyze whether a second-order latent variable structure for episodic and semantic memory was invariant across age groups and across noise exposure conditions. Data were taken from three previous experimental noise studies that were performed with the same design, procedure, and dependent measures, and with participants from four age groups (13-14, 18-20, 35-45, and 55-65 years). Two noise conditions, road traffic noise and meaningful irrelevant speech, were compared to a quiet control group. The structural models put to the test were taken from Nyberg et al. (2003), which employed several memory tests that were the same as ours and studied age-groups that partly overlapped with our groups. In addition we also varied noise exposure conditions. Our analyses replicated and supported the second-order semantic-episodic memory models in Nyberg et al. (2003). The latent variable structures were invariant across age groups, with the exception of our youngest group, which by itself showed a less clear latent structure. The obtained structures were also invariant across noise exposure conditions. We also noted that our text memory items, which did not have a counterpart in the study by Nyberg et al. (2003), tend to form a separate latent variable loading on episodic memory.     

A SOCIAL ECOLOGY OF HYPERACTIVE BOYS: MEDICATION EFFECTS IN STRUCTURED CLASSROOM ENVIRONMENTS

Hyperactive boys on methlyphenidate (Ritalin), hyperactive boys on placebo, and comparison boys were observed in quasi-naturalistic classroom settings. Ambient stimulation (quiet versus noisy conditions) and source of regulation (self-paced versus other-paced activities) were varied in a 2 × 2 design. Compared to their peers, hyperactive boys on placebo showed lower rates of task attention and higher rates of gross motor movement, regular and negative verbalization, noise-making, physical contact, social initiation, disruption, and acts that were perceived as energetic, inappropriate, or unexpected. Self-paced activities resulted in increased rates of verbalization, social initiation, and high-energy episodes. High ambient noise levels reduced task attention and increased the rates of many other behaviors including verbalization, physical contact, gross motor movement, and high-energy acts. Medication-by-situation interactions emerged for both classroom dimensions, with hyperactive boys on placebo being readily distinguishable from their peers under some classroom conditions and indistinguishable under other conditions. Moderate relationships were found between teacher ratings and many individual behavior categories. Discussion focused on (a) the merits and limitations of a social ecological research perspective, and (b) the implications of these findings for the design of intervention strategies.     

Perceived control in continuous loud noise

The effects of two types of perceived control were assessed for performance during and following exposure to continuous loud noise at 90 dBC. Subjects performed a tracking task during exposure and the Stroop test in the period following exposure. Control could be effected either (1) by attenuating the intensity of the noise or (2) by reducing the difficulty of the tracking task. In both cases subjects were encouraged not to exercise control. Performance in treatments involving loud (90 dBC) and soft (55 dBC) noise served as baseline conditions. Perceived control of task difficulty accentuated the tendency for root-mean-square error to rise during the tracking task. There were no significant effects of noise intensi ty on tracking performance. Loud noise reduced the incidence of errors in the Stroop test but perceived control failed to influence this effect. The results are discussed in terms of the generality of perceived control phenomena.     

Noise and levels of processing

Three experiments investigated the view that people make more use of relatively surface levels of coding when noise is present, neglecting semantic levels of analysis. In experiment 1 subjects classified words in different ways and then recalled as many as possible. Subjects who received the noise conditions in the order noise-quiet recalled more words than those who received the conditions in the order quiet-noise, but noise failed to interact with the nature of the classification conditions although the usual advantage of the semantic condition over letter-case and rhyme conditions was obtained. Experiment 2 failed to show any effect of noise on physical-name match differences when letter pairs were presented simultaneously. In experiment 3 a delay was introduced between the letters; the noise-quiet subjects were then faster on the physical match than the name match whereas the slower quiet-noise subjects showed the reverse pattern. This could represent an instance of asymmetric transfer from noise to quiet or it could be due to speed per se.Overall, these results argue against a general explanation of noise effects in terms of a passive shift in levels of processing.     

The Effect of Attention Allocation Instructions on Self-paced Task Performance under Quiet and Distracted Conditions

This study examined the effectiveness of external and internal focusing attention instructions on the performance of three throwing tasks under both quiet and distracted conditions. The main finding was that during acquisition, the external focus of attention led to improved performance when compared to internal focus of attention and control, but only under quiet conditions. It was also found that during auditory and visual distraction conditions, both types of focus attention produced similar levels of performance, and both groups were superior to the control condition. It is suggested that sport psychology consultants provide their athletes with external focusing attention instructions.     

Classroom experiments on the effects of different noise sources and sound levels on long‐term recall and recognition in children

A total of 1358 children aged 12–14 years participated in ten noise experiments in their ordinary classrooms and were tested for recall and recognition of a text exactly one week later. Single and combined noise sources were presented for 15 min at 66 dBA L_eq (equivalent noise level). Single source presentations of aircraft and road traffic noise were also presented at 55 dBA L_eq. Data were analysed between subjects since the first within‐subjects analysis revealed a noise after‐effect or a asymmetric transfer effect. Overall, there was a strong noise effect on recall, and a smaller, but significant effect on recognition. In the single‐source studies, aircraft and road traffic noise impaired recall at both noise levels. Train noise and verbal noise did not affect recognition or recall. Some of the pairwise combinations of aircraft noise with train or road traffic, with one or the other as the dominant source, interfered with recall and recognition. Item difficulty, item position and ability did not interact with the noise effect. Arousal, distraction, perceived effort, and perceived difficulty in reading and learning did not mediate the effects on recall and recognition. Copyright © 2003 John Wiley & Sons, Ltd.     

Perception of Native English Reduced Forms in Adverse Environments by Chinese Undergraduate Students

Previous research has shown that learners of English-as-a-second-language (ESL) have difficulties in understanding connected speech spoken by native English speakers. Extending from past research limited to quiet listening condition, this study examined the perception of English connected speech presented under five adverse conditions, namely multi-talker babble noise, speech-shaped noise, factory noise, whispering and sad emotional tones. We tested a total of 64 Chinese ESL undergraduate students, using a battery of listening tasks. Results confirmed that the recognition of English native speech was more challenging for Chinese ESL learners under unfavorable listening conditions, in comparison to a noise-free listening condition. These findings carry significant implications for the importance of training and assessments on connected speech perception across various listening environments.     

Noise and the "rehearsal-masking hypothesis"

This study examines the proposal that continuous loud noise impairs short-term recall by masking the inner speech necessary to rehearse material in memory (Poulton, 1976 a, 1977 b). The "masking hypothesis" contrasts with previous theories which relate recall impairment in noise to the latter's action in over-arousing the individual or inducing changes in attentional deployment. Separate groups performed a visual, serial eight-consonant recall task in either 92 dBA "noise" or 75 dBA "quiet" and in "normal" or "suppressed" rehearsal conditions. The masking hypothesis predicted that noise would impair recall relative to quiet in normal rehearsal conditions. But where the rehearsal of both groups was already suppressed by a concurrent articulatory task, recall would not differ between the groups through noise-masking then being irrelevant. Total correct recall scores appeared to confirm the masking hypothesis but the pattern of serial order recall showed differences between noise and quiet in suppressed rehearsal conditions which seemed better explained by an attentional influence of noise. Further, reduced commission and acoustic confusion errors in noise were not consistent with the predictions of the masking hypothesis. It was concluded that noise-masking could not be refuted but that attentional changes due to the arousing action of noise might also be active determinants of recall.