Attentional processes in time perception: effects of mental workload and event structure

The role of attention in timing was evaluated in 2 experiments. In Experiment 1, participants reproduced the durations of melodies with either a coherent or an incoherent structure. Participants were tested under control (timing only) and detection (timing plus target detection) workload conditions. Reproductions were shorter and more inaccurate under detection conditions, and incoherent event structure extended the effect to a wider range of durations. In Experiment 2, participants reproduced the durations of auditory prose passages that represented 3 levels of mental workload and 3 levels of event structure. Both increases in workload and the degradation of structure led to inaccurate reproductions. The results point to the central role of attention in temporal experience.     

社交焦虑个体对正性面孔刺激的解释偏差

本研究分别在短时（60ms）和长时（无时间限制）条件下呈现匹配的正性和中性面孔,要求高、低社交焦虑被试选择更具威胁性的面孔,以验证两者对正性刺激是否存在主观解释偏差,并考察该偏差产生于认知加工的哪一阶段。结果发现,长时条件下,高焦虑组选择正性面孔的比例显著高于低焦虑组;短时条件下无显著差异。提示高社交焦虑个体对正性刺激存在主观、外显的解释偏差,他们更倾向于对正性刺激做出消极解释,并且这种偏差产生于认知加工的后期。     

The effects of valence and arousal on the emotional modulation of time perception: evidence for multiple stages of processing

Previous research has demonstrated that both emotional valence and arousal can influence the subjective experience of time. The current research extends this work by (1) identifying how quickly this emotional modulation of time perception can occur and (2) examining whether valence and arousal have different effects at different stages of perception. These questions were addressed using a temporal bisection task. In each block of this task, participants are trained to distinguish between two different exposure durations. Participants are then shown stimuli presented at a number of durations that fall between the two learned times, and are asked to indicate whether the test stimulus was closer in duration to the shorter or longer learned item. In the current study, participants completed blocks of trials in which the durations were "Short" (100-300 ms) or "Long" (400-1600 ms). Stimuli consisted of neutral photographs as well as four categories of emotional images: high-arousal negative, high-arousal positive, low-arousal negative, and low-arousal positive. In Short blocks, arousing and nonarousing negative images were judged to have been shown for shorter durations than they actually were (i.e., the duration was underestimated); this effect occurred at durations as brief as 133 ms. In Long blocks, the display time for highly arousing negative items was overestimated, whereas durations were underestimated for highly arousing positive items and less arousing negative items. These data suggest that arousal and valence have different effects at different stages of perception, possibly due to the different neural structures involved at each stage of the emotional modulation of time perception.     

The effects of intertrial interval and instructional format on skill acquisition and maintenance for children with autism spectrum disorders

We replicated and extended the study by Koegel, Dunlap, and Dyer (1980) by examining the effects of 3 intertrial‐interval (ITI) durations on skill acquisition in 2 children with autism spectrum disorders. Specifically, we compared the effect of short (2 s), progressive (2 s to 20 s), and long (20 s) ITIs on participants’ mastery of tacts or intraverbals presented in massed‐trial and varied‐trial instructional formats. We also measured (a) stereotypic and problem behavior during the ITI, (b) maintenance of skills, and (c) responding to novel adults and settings. Results showed that short ITIs in a varied‐trial format produced the most efficient acquisition of skills; however, most ITI durations produced more efficient skill acquisition in a varied format compared to a massed format. The trial format and ITI duration associated with the lowest levels of stereotypic and problem behavior during the ITI and responding during maintenance and novel adult and setting probes differed across participants.     

Interval-timing deficits in individuals at high risk for schizophrenia

A duration-bisection procedure was used to study the effects of signal modality and divided attention on duration classification in participants at high genetic risk for schizophrenia (HrSz), major affective disorder (HrAff), and normal controls (NC). Participants learned short and long target durations during training and classified probe durations during test. All groups classified visual signals as shorter than equivalent duration auditory signals. However, the difference between auditory and visual signal classification was significantly larger for the HrSz group than for the NC group. We posit a model in which there is a clock rate difference between auditory and visual signals due to an attentional effect at the level of a mode switch that gates pulses into an accumulator. This attentionally mediated clock rate difference was larger for the HrSz participants than for the NC participants, resulting in a larger auditory/visual difference for the HrSz group.     

Stimulus Exposure Duration in a Deployment-of-Attention Task: Effects on Dysphoric,Recently Dysphoric,and Nondysphoric Individuals

Examined attentional deployment of dysphoric, unstable, and stable nondysphoric individuals using the Deployment-of-Attention Task (DOAT) while randomly varying stimulus exposure durations. Previous research indicates a nondepressed “protective” bias in attention whereas depressed individuals evidence no bias. The current study examined the possibility that depressed participants' lack of bias may actually reflect inattention to briefly presented stimuli, possibly due to slowed processing seen in depression (i.e. psychomotor retardation). Participants completed the DOAT, viewing stimuli at four presentation durations randomised across trials. Results indicated that dysphoric participants displayed no attentional bias even at extended presentation durations, whereas nondysphoric participants showed a “protective” bias. Within the nondysphoric group, unstable nondysphoric participants displayed a more pronounced protective bias than did stable nondysphorics.     

短时距估计中的标量特性

使用单任务研究程序,采用预期式研究范式和再现时距的研究方法,从心理物理学的视角,通过三个实验系统地考查了人类短时距估计的标量特性、变异源、时距估计中的转换点和韦伯函数的形态等问题。结果表明,刺激物的运动、变化、速度和物理时距是被试进行短时距估计的重要变异源;被试在实验中表现出高估较短时距和低估较长时距的倾向,时距估计的转换点为11.1s;计时过程中得到的韦伯函数是个分段连续函数, 韦伯函数的拐点有两个12s和21s,这两点与本研究得到的时距估计转换点具有部分一致性     

Distinct task-independent visual thresholds for egocentric and allocentric information pick up

The dominant view of the ventral and dorsal visual systems is that they subserve perception and action. De Wit, Van der Kamp, and Masters (2011) suggested that a more fundamental distinction might exist between the nature of information exploited by the systems. The present study distinguished between these accounts by asking participants to perform delayed matching (perception), pointing (action) and perceptual judgment responses to masked Müller-Lyer stimuli of varying length. Matching and pointing responses of participants who could not perceptually judge stimulus length at brief durations remained sensitive to veridical stimulus length (egocentric information), but not the illusion (allocentric, context-dependent information), which was effective at long durations. Distinct thresholds for egocentric and allocentric information pick up were thus evident irrespective of whether perception (matching) or action (pointing) responses were required. It was concluded that the dorsal and ventral systems may be delineated fundamentally by fast egocentric- and slower allocentric information pick up, respectively.     

Global interference: the effect of exposure duration that is substituted for spatial frequency

In this study, participants were required to identify hierarchically structured patterns that appeared at either global or local level. Paquet and Merikle (1984 Canadian Journal of Psychology 381 45-53) showed that global interference is affected by exposure duration in the processing of a hierarchical structure. They showed that only global-to-local interference occurred at short exposure durations. In contrast, global-to-local as well as local-to-global interference was observed at long exposure durations. They suggested that the effect of exposure duration with global interference depends on the high-spatial-frequency versus low-spatial-frequency channel. In the present study, exposure duration (short or long) was varied randomly from trial to trial (experiment 1), or held constant (experiment 2). In experiment 1, global-to-local interference occurred at both short and long exposure durations, even though the same physical properties existed as in experiment 2. In experiment 2, both global-to-local and local-to-global interference occurred at only long exposure durations, in line with the results reported by Paquet and Merikle. This suggests that the effect of exposure duration on global interference is explained not only by spatial-frequency channels, but also by attentional shift.     

Solving the chicken-and-egg problem of letter detection and fixation duration in reading

When asked to detect target letters while reading a text, participants miss more letters in frequent function words than in less frequent content words. According to the truncation assumption that characterizes most models of this effect, misses occur when word-processing time is shorter than letter-processing time. Fixation durations for detections and omissions were compared with fixation durations from a baseline condition when participants were searching for a target letter embedded in different words. Although, as predicted by truncation, fixation durations were longer for detections than for omissions, fixation durations for detections were also longer than those for the same words in the baseline condition, demonstrating that longer fixation durations when targets are detected are more likely to be due to demands associated with producing a detection response than to truncation. Also, contrary to predictions from the truncation assumption, the standard deviation of fixation durations for detections was larger than that from the baseline condition.     

Searching for an O in an array of Cs: eye movements track moment-to-moment processing in visual search

We examined how closely the underlying cognitive processing in a visual search task guides eye movements by comparing two different search tasks. In the extended search task, participants searched for an O in eight clusters of Landolt Cs with varying gap widths (four characters per cluster, arranged to look like words in text). In the single-cluster task, participants searched a single cluster (identical to the ones in the extended search). The key manipulation was gap size; although gap orientation for the distractors varied within a cluster, gap size was constant within a cluster but differed in size from cluster to cluster. The principal findings were that (1) gaze durations in the extended search were almost completely a function of the difficulty of the cluster (i.e., the gap size of the Cs) and (2) the effect of gap size on gaze durations in the extended search was very similar to its effect on response times in the single-cluster search. Thus, it appears that eye movements in the search task are determined almost exclusively by the ongoing cognitive processing on that cluster.     

Estimating averages from distributions of tone durations

We examined whether estimating average duration was influenced by the distribution peak location. We presented participants with samples of various tone durations and then presented comparison tone durations. Participants judged whether each comparison duration was longer than the average sample duration. Estimates of the averages were inferred from the psychophysical functions. The durations were sampled from three distributions: one positively skewed, one symmetric, and one negatively skewed. In Experiment 1, every participant was presented with every distribution. Estimates of the averages were unbiased for the symmetric distribution but were biased toward the long tail of each skewed distribution. This would occur if participants combined the sample to be judged with the previous, irrelevant samples, or with the comparison durations. In Experiment 2, each participant was presented with samples from only one of the distributions. Estimates of the averages were still biased toward the long tails of the skewed distributions. This would occur if participants combined the sample to be judged with the comparison durations, which were the same for the three distributions. In Experiment 3, each participant was presented with only one distribution, and each distribution was tested with its own comparison durations, selected as percentiles from the distribution. The estimates were accurate for the smallest population mean (positively skewed distribution) but underestimated the larger means. These results could be explained by subjective shortening of the durations in memory, with a simple equation from scalar timing theory. This equation correctly predicted two results: The estimated averages were a linear function of the stimulus means, and the variances were a linear function of the squared stimulus means. Neither prediction was dependent on the skewness of the stimulus durations.     

Dynamics of balancing space and time in memory: tau and kappa effects revisited

In 3 experiments, the authors studied the organization of spatiotemporal information in memory. Stimuli consisted of configurations of dots, presented sequentially. The stimuli were either proportional, with interdot distances corresponding to interdot durations, or not proportional, with interdol distances not corresponding to interdot durations. After a learning phase, participants reproduced the spatial (Experiment 1), temporal (Experiment 2), or spatial and temporal (Experiment 3) characteristics of the target 60 times in succession. In the nonproportional conditions, effects of variable interdot durations or distances on the reproduction of, respectively, constant distances (tau effect) or durations (kappa effect) were observed, whereas no such effects were observed when variable distances or durations were to be produced. Tau and kappa effects influenced the accuracy but not the variability of responses. The results are discussed in light of the distinction between properties of the stabilized mental image and the process of stabilization.     

Technology‐based contingency management and e‐cigarettes during the initial weeks of a smoking quit attempt

Contingency management (CM) interventions are among the most effective behavioral interventions for smoking. This study assessed the effects of CM and electronic cigarettes (ECs) on smoking reductions and abstinence for durations of 30‐36 days. Twelve participants were exposed to Baseline, EC alone, and EC + CM conditions. An internet‐based platform was used to monitor smoking via breath carbon monoxide (CO) and deliver CM for smoking abstinence (CO ≤4 ppm). A Bluetooth‐enabled EC monitored daily EC puffs. Abstinence rates were equivalent between EC (34.4%) and EC + CM (30.4%) conditions. Both conditions promoted smoking reductions. We observed an inverse correlation between smoking and EC puffs (r = ‐.62, p < .05). Results suggest the use of electronic cigarettes can promote smoking reductions and abstinence, and CM did not improve these outcomes. Larger magnitude consequences or tailoring EC characteristics (e.g., flavor) may have improved outcomes. Technology‐based methods to collect intensive, longitudinal measures of smoking and electronic cigarette use may be useful to characterize their environmental determinants.     

The relativity of time perception produced by facial emotion stimuli

We systematically examined the impact of emotional stimuli on time perception in a temporal reproduction paradigm where participants reproduced the duration of a facial emotion stimulus using an oval-shape stimulus or vice versa. Experiment 1 asked participants to reproduce the duration of an angry face (or the oval) presented for 2,000 ms. Experiment 2 included a range of emotional expressions (happy, sad, angry, and neutral faces as well as the oval stimulus) presented for different durations (500, 1,500, and 2,000 ms). We found that participants over-reproduced the durations of happy and sad faces using the oval stimulus. By contrast, there was a trend of under-reproduction when the duration of the oval stimulus was reproduced using the angry face. We suggest that increased attention to a facial emotion produces the relativity of time perception.     

Social anxiety and interpretation biases for facial displays of emotion: emotion detection and ratings of social cost

The current study assessed the processing of facial displays of emotion (Happy, Disgust, and Neutral) of varying emotional intensities in participants with high vs. low social anxiety. Use of facial expressions of varying intensities allowed for strong external validity and a fine-grained analysis of interpretation biases. Sensitivity to perceiving negative evaluation in faces (i.e., emotion detection) was assessed at both long (unlimited) and brief (60 ms) stimulus durations. In addition, ratings of perceived social cost were made indicating what participants judged it would be like to have a social interaction with a person exhibiting the stimulus emotion. Results suggest that high social anxiety participants did not demonstrate biases in their sensitivity to perceiving negative evaluation (i.e. disgust) in facial expressions. However, high social anxiety participants did estimate the perceived cost of interacting with someone showing disgust to be significantly greater than low social anxiety participants, regardless of the intensity of the disgust expression. These results are consistent with a specific type of interpretation bias in which participants with social anxiety have elevated ratings of the social cost of interacting with individuals displaying negative evaluation.     

数字加工任务影响时距知觉的数字效应

本研究采用复制时距和数字加工双任务,探讨数字大小影响时距知觉的机制。实验首先呈现不同时距的圆点,然后让被试按键复制圆点呈现的时距,与此同时,对屏幕上出现的数字进行命名(实验1)、奇偶数判断(实验2)、大小判断(实验3)。实验结果发现对数字进行奇偶数判断时,数字大小对时距知觉没有影响;进行数字命名和大小判断任务时,数字大小对时距知觉都产生了影响,并且时距不同,数字大小对时距知觉的影响也不同。该结果表明时距知觉的数字效应与数字加工任务和时距长短有关,呈现出动态变化的过程。     

Mental time travel: Effects of trial duration on episodic and semantic content

Studies exploring mental time travel commonly use cue-word paradigms to elicit past and future autobiographical events. However, the effect of trial duration (how long participants are allowed to describe events) on the relationship between episodic and nonepisodic detail and episodic specificity (i.e., whether longer durations increase event specificity) has not been examined. To resolve these issues, a cue-word study was devised whereby participants described past and future events under three randomly administered time constraints: short (1-min), standard (3-min), and long (5-min) durations. Findings indicated that an individual's capacity for episodic and nonepisodic thought for the past and future were unrelated. This lends supports to the idea that independent mechanisms are responsible for episodic and semantic information. This study also offers clarity concerning the effect of different trial durations on episodic specificity, which may aid the design of future studies of mental time travel.     

Effects of an Internet-based voucher reinforcement program for smoking abstinence: a feasibility study

The present study tested the feasibility of an Internet-based method to obtain objective evidence of smoking abstinence and to deliver vouchers for evidence of abstinence. Four heavy smokers participated in this 4-week study. Twice daily, participants made video recordings of themselves providing a breath carbon monoxide (CO) sample with a Web camera. The video was sent electronically to the smoking clinic. Participants could earn vouchers for gradual reductions in breath CO during an initial shaping condition, and then for achieving abstinence (CO < or = 4 ppm). Vouchers could be exchanged for merchandise at select Internet vendors. Relative to baseline conditions, participants substantially reduced their smoke intake, and 3 achieved sustained periods of abstinence. The study suggests that an Internet-based voucher reinforcement program is a feasible method to promote abstinence from cigarette smoking.     

Discrimination of differences in digitally manipulated phoneme length during speech

The present study investigated differences in the thresholds of phoneme duration in word and sentence contexts by participants' sex. In the word condition, 27 participants listened to two pairs of words in a dual pair discrimination task. One pair contained the same durations of /s/, and the other pair contained different durations of /s/. Participants were to select the pair which contained different durations of /s/ in the words. In the sentence condition, the other set of 27 participants listened to two pairs of sentences and selected the pair containing different durations of /s/ in the sentences. Throughout these tasks, the participants' just-noticeable-difference and trials-to-completion were analyzed. The results showed that the participants demonstrated better performance in detecting just-noticeable-difference in the sentence condition than in the word condition. In addition, a sex difference was found in just-noticeable-difference in both conditions with better performance in men than women. No significant differences in trials-to-completion were found in either condition.