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'.     

Word recognition in loud noise

Loud noise has been shown to bias environmental stimulus selection to high-priority or ‘dominant’ task and stimulus features while causing relative neglect of less dominant aspects. The present concern was whether a similar influence of noise would occur when selecting, or rather, retrieving information from memory. Separate groups performed a semantic recognition task in 95 dB(A) ‘noise’ or 70 dB(A) ‘quiet’ conditions. Recognition of semantically ‘high-dominance’ words was reliably faster in noise but ‘low-dominance’ recognition was not impaired relative to performance in quiet conditions. On this basis, the results only partially support a possible common principle governing selection of environmental and memorial information in noise. However, they confirm Eysenck's (1975) contention that arousal may affect retrieval processes (in addition to initial learning) and that failure to account for the former influence may obscure inferences drawn from previous research.     

Effect of loud noise on attentional selectivity

The effects of loud noise are examined by observing its influence upon a combined tracking and multi-source monitoring task. Tracking (the primary task) improves in noise, as does the detection of centrally located signals in the monitoring task. Peripheral signals are detected less often in noise. The data are interpreted in terms of increased selectivity of attention with arousal.     

Hearing speech in noise: seeing a loud talker is better

Seeing the talker improves the intelligibility of speech degraded by noise (a visual speech benefit). Given that talkers exaggerate spoken articulation in noise, this set of two experiments examined whether the visual speech benefit was greater for speech produced in noise than in quiet. We first examined the extent to which spoken articulation was exaggerated in noise by measuring the motion of face markers as four people uttered 10 sentences either in quiet or in babble-speech noise (these renditions were also filmed). The tracking results showed that articulated motion in speech produced in noise was greater than that produced in quiet and was more highly correlated with speech acoustics. Speech intelligibility was tested in a second experiment using a speech-perception-in-noise task under auditory-visual and auditory-only conditions. The results showed that the visual speech benefit was greater for speech recorded in noise than for speech recorded in quiet. Furthermore, the amount of articulatory movement was related to performance on the perception task, indicating that the enhanced gestures made when speaking in noise function to make speech more intelligible.     

Memorization of young people under loud pink noise of short duration

Exposure of students to loud pink noise of short duration in schools with high background noise showed that memorization of the students under loud pink noise is correlated with noise level. For levels up to 91.5 dB(A) the performance of 275 students improved, but for louder noise performance was reduced.     

Perceived control

Permitting subjects to choose materials to be learned on a task enhances performance on that task. These results support the idea that choice increases the learner's perception of control, thereby enhancing motivation and performance. The purpose of the present experiments was to determine whether choosing responses to be learned on a paired-associate task would also benefit performance on a reaction-time task. Half of the subjects selected their responses to be learned on a paired-associate task while the remaining subjects were assigned responses. In one experiment, subjects then performed both the PA and RT tasks simultaneously, while in the second experiment the RT task was performed following the choice/force procedure. Providing the learner with the opportunity to choose produced a generalized increase in motivation, which resulted in significantly faster responding on the nonchosen RT task. Also discussed are the limitations of the effects of perceived control.     

Perceived control and health

Perceived control (PC) is defined as thebelief that one can determine one’s own internal states and behavior, influence one’s environment, and/or bring about desired outcomes. Two important dimensions of PC are delineated: (1) whether the object of control is located in the past or the future and (2) whether the object of control is over outcome, behavior, or process. A variety of constructs and measures of PC (e.g., efficacy, attribution, and locus of control) are discussed in relation to these dimensions and selected studies are reviewed. The issues, controversies, and limits of the research on perceived control and health are addressed in terms of the antecedents and consequences of perceived control. Investigations should clearly conceptualize the object of perceived control, use measures that match the conceptualization, and when attempting to manipulate control, directly measure perceived control. The relation between PC and health outcomes is complex, and different aspects of PC may interact to affect health outcomes.     

Perceived control and health

Perceived control (PC) is defined as thebelief that one can determine one’s own internal states and behavior, influence one’s environment, and/or bring about desired outcomes. Two important dimensions of PC are delineated: (1) whether the object of control is located in the past or the future and (2) whether the object of control is over outcome, behavior, or process. A variety of constructs and measures of PC (e.g., efficacy, attribution, and locus of control) are discussed in relation to these dimensions and selected studies are reviewed. The issues, controversies, and limits of the research on perceived control and health are addressed in terms of the antecedents and consequences of perceived control. Investigations should clearly conceptualize the object of perceived control, use measures that match the conceptualization, and when attempting to manipulate control, directly measure perceived control. The relation between PC and health outcomes is complex, and different aspects of PC may interact to affect health outcomes.     

Variability and noise in continuous force production

In the present 3 experiments, the authors examined the hypothesis, derived from information theory, that increases in the variability of motor responses result from increases in perceptual-motor noise. Three different groups of participants (Ns = 10, 9, and 10, respectively, in Experiments 1, 2, and 3) produced continuous isometric force under either low, intermediate, or high target force levels. When considered together, the results showed that force variability (SD) increased exponentially as a function of force level. However, an index of information transmission (M/SD), as well as measures of noise in both the time (approximate entropy) and the frequency (power spectrum) domains, changed according to an inverted-U-shaped function over the range of force levels. The findings provide further evidence that increased information transmission is related to increases, and not to decreases, in the noisiness of the structure of force output.     

Effect of unpleasant loud noise on hippocampal activities during picture encoding: an fMRI study

The functional link between the amygdala and hippocampus in humans has not been well documented. We examined the effect of unpleasant loud noise on hippocampal and amygdaloid activities during picture encoding by means of fMRI, and on the correct response in humans. The noise reduced activity in the hippocampus during picture encoding, decreased the correct response and increased the activity of the amygdala. A path diagram using structural equation modeling suggested that hippocampus activity might be depressed by high amygdala activity. Therefore, noise should diminish memory by reducing hippocampal activity, which might be depressed by high amygdala activity.     

Perceived stress and diabetes control in adolescents

Studies of diabetes control have traditionally focused on patients' regulation of insulin, diet, and exercise. Although psychosocial stress may also influence blood glucose, researchers have infrequently accounted for the three primary physiological factors when estimating the effects of stress. In addition, few investigators have considered the influence of everyday minor stressors on health outcome. The Tennessee Camp for Diabetic Children provided an opportunity to monitor insulin administration, dietary intake, and exercise levels and to obtain measures of blood glucose and perceived minor stressors. The best index of stress was one in which number and magnitude of negative stressors were combined into a cumulative stress measure. Negative cumulative stress significantly correlated with blood glucose levels after controlling for the effects of insulin, diet, and exercise. In addition, diabetes control tended to be better when adolescents, particularly boys, adjusted well to negative stress. These findings suggest that minor stressors can influence health outcome, but positive and negative stress need to be assessed independently.     

Perceived control and anxiety in Portuguese children

The central role of perceived control in the development of anxiety disorders is proposed by several theoretical models. The main objective of the present study was to examine the relation between perceived control and anxiety in Portuguese school-age children. To accomplish this objective we developed the Portuguese short form of the Anxiety Control Questionnaire for Children (ACQ-C, Weems, 2005; Pereira & Barros, 2010), whose psychometric studies are presented. The sample comprised 238 children, aged 8 to 15 years, from the general population attending Portuguese schools. Children completed measures of perceived control (ACQ-C) and their anxiety (Screen for Child Anxiety Related Emotional Disorders--Revised, SCARED-R). The psychometric studies indicate good psychometric characteristics of the Portuguese ACQ-C short form, in particular a high internal consistency (a = .85) and an adequate temporal stability (r = .60, p = .002). Results show a significant negative association between perceived control and anxiety symptomatology, providing partial support for models that assign a central role to control beliefs in explaining the development of anxiety disorders. These results also suggest the importance of considering the perception of control as a prime target for preventive actions and intervention aimed at reducing anxiety in school aged children.     

Effects of red light and loud noise on the rate at which monkeys sample the sensory environment.

Monkeys, given the opportunity to move between two featureless chanbers, 'sample' first one, then the other in a way which reflects a Poisson decision process. The rate of sampling is higher in red light than in blue and in loud noise than in quietness. We suggest that monkeys 'tune' their sampling rate to the a priori probability of change in the environment.     

Perceived and actual control in EMG treatment of back pain

The aim of this study was to investigate the hypothesis that the perception of the apparent amount of voluntary control over muscle activity determines the efficacy of EMG biofeedback treatment in back-pain patients. Twenty-four patients with nonorganic or minor organic back pain were randomly assigned to three training conditions: low-success, high-success and linear feedback of training performance. Contrary to expectations about the relationship between perceived control over muscle tension and pain, no differences in the effects of treatment were found between these three experimental groups. Statistically and clinically significant treatment gains were, however, found in all groups. Thus, the hypothesis of a relationship between perceived muscle tension reduction and pain reports in chronic back-pain patients is not confirmed. After a close analysis of the training sessions, and the muscle activity reduction actually obtained, an alternative hypothesis about EMG biofeedback training procedures is formulated.