Woods et al. (2015) claim that secular Simple Reaction Time (SRT) slowing (Woodley et al. 2013), disappears once modern studies are corrected for software and hardware lag, and once Galton’s data are corrected for fastest-response selection. Here, this is challenged with a reanalysis of the secular slowing of SRT in the UK amongst large (N>500), population-representative age-matched (≊18-30 years) studies. Starting with Galton’s sample, this is assigned the simulated value estimated by Dodonova and Dodonov (2013, who like (...) Woods et al. were critical of secular SRT slowing, owing to measurement issues) on the basis that he collected the fastest of three trials (207.5ms). The two sexes in Galton’s study are combined (as in Woods et al.), raising the weighted sample mean to 208.5ms. Next is the Wilkinson and Alison (1989) study, which attempted to replicate Galton’s study one century later, collecting SRTs as part of an exhibit in the London Science Museum. An electronic chronoscope recorded SRTs on magnetic tape, and sampled over eight trials with micro-processor-determined variable foreperiods. The mean SRT value for the 1,189 participants aged between 20 and 29 is 245ms. The presence of long and variable foreperiods necessitates a penalty of 10ms (Dodonova & Dodonov, 2013). Another 10ms should be deducted based on key-pressing time (Dodonova & Dodonov, 2013), reducing the mean to 225ms. The studies of Deary and Der (2005) and Der and Deary (2006) are also included. The first utilized the highly representative Scottish Twenty-07 cohort. Dodonova and Dodonov (2013) identified a 53ms lag stemming from liquid crystal stimulus onset delay. This is subtracted from the weighted average of the two sexes (300.8ms), along with another 10ms for key-pressing time. The resultant mean is 237.8ms.Dodonova and Dodonov (2013) cleaned the male data in the Der and Deary (2006) study, collected from the representative UK Health and Lifestyle Survey, by removing cases for which SRT standard deviations exceeded those for choice RT. This reduced the N from 834 to 661, and also reduced the mean from 300ms to 284ms. The estimate was also penalized for LCD onset delay and key-pressing time, reducing the mean to 221ms. When the SRT value for the female sample is penalized equivalently the resulting value is 239ms. In order to simulate the female N for the purposes of taking a weighted average of both sexes, the actual female N is reduced in proportion to the male N (79.3%=881), yielding a weighted mean of 230.9ms for a combined sample-size of 1,472. Table 1 presents the data used in the analysis.Table 1 SRT means, sample sizes and sampling years for four large, age-matched UK samples[Table 1 here]Consistent with Dodonova and Dodonov (2013), N-weighted regression is employed, as the only data on sample variability is sample size. Figure 1 illustrating the secular trend in UK SRT over 100 years.[Figure 1 here] Figure 1. Secular SRT slowing across four large, representative studies from the UK spanning a century. Bubble-size is proportional to sample size. Combined N=6,622. The secular slowing between UK studies is statistically significant (β=0.97; 95% CI=0.969 to 0.971, N=6,622), at –22.8ms a century. Additional evidence for generational SRT slowing comes from Verhaeghen (2014), who suggested that the ratio of longitudinal to cross-sectional age-related slowing might tentatively infer generational changes in processing speed. Verhaeghen reports ratios for two SRT studies (0.91 and 1.15), implying both secular losses and gains. For the study of Deary and Der (2005), the SRT ratios are “censored because they were excessively large” (p. 256). In this study, the ratio of the cross-sectional slowing trend (taking the weighted average of all paired between-cohort differences rescaled in terms of change per decade for males and females), to the weighted average decadal longitudinal slowing trend for both the males and females is 0.73, for an N of 1,926 (cf. Woodley et al., 2014b, for a detailed reanalysis of this dataset). The weighted average of the three SRT ‘Verhaeghen ratios’ is 0.9 (N=4,078) – tentatively consistent with generational declines (i.e. a ratio of <1). In conclusion Woods et al. (2015) have undoubtedly made an important contribution to the debate concerning the role of software and hardware lag in the inflation of contemporary estimates of SRT, however the evidence for generational SRT slowing remains quite compelling. ReferencesDeary, I.J., & Der, G. (2005). Reaction time, age, and cognitive ability: Longitudinal findings from age 16 to 63 years in representative population samples. Aging, Neuropsychology, and Cognition, 12, 187–213.Der, G., & Deary, I.J. (2006). Age and sex differences in reaction time in adulthood: Results from the United Kingdom Health Lifestyle Survey. Psychology and Aging, 21, 62–73.Dodonova, Y.A., & Dodonov, Y.S. (2013). Is there any evidence of historical slowing of reaction time? No, unless we compare apples and oranges. Intelligence, 41, 674–687.Galton, F. (1890). Exhibition of instruments (1) for testing the perception of differences of tint, and (2) for determining reaction-time. Journal of the Anthropological Institute, 19, 27–29.Verhaeghen, P. (2014). The elements of cognitive aging: Meta-analyses of age-related differences in processing speed and their consequences. Oxford: Oxford University Press.Wilkinson, R.T., & Allison, S. (1989). Age and simple reaction time: Decade differences for 5,324 subjects. Journal of Gerontology, 44, 29–35.Woodley, M.A., Madison, G., & Charlton, B.G. (2014b). Possible dysgenic trends insimple visual reaction time performance in the Scottish Twenty-07 cohort: Areanalysis of Deary & Der (2005). Mankind Quarterly, 55, 110-124.Woodley, M.A., te Nijenhuis, J., & Murphy, R. (2013). Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time. Intelligence, 41, 843–850.Woods, D.L., Wyma, J.M., Yund, E.W., Herron, T.J., & Reed, B. (2015). Factors influencing the latency of simple reaction time. Frontiers in Human Neuroscience, 9:131. (shrink)

Processing the motivational relevance of a visual scene and reacting accordingly is crucial for survival. Previous work suggests the emotional content of naturalistic scenes affects response speed, such that unpleasant content slows responses whereas pleasant content accelerates responses. It is unclear whether these effects reflect motor-cognitive processes, such as attentional orienting, or vary with the function/outcome of the motor response itself. Four experiments manipulated participants’ ability to terminate the picture and, thereby, the response’s function and motivational (...) value. Attentive orienting was manipulated via picture repetition, which diminishes orienting. A total of N = 81 participants completed versions of a go/no-go task, discriminating between distorted versus intact pictures drawn from six content categories varying in positive, negative, or neutral valence. While all participants responded faster with repetition, only participants without offset control exhibited slower responses to unpleasant and accelerated responses to pleasant content. Emotional engagement, measured by the late positive potential, was not modulated by attentional orienting, suggesting that the interaction between repetition and offset control is not due to altered emotional engagement. Together, results suggest that response time changes as a function of emotional content and sensitivity to attention orienting depends on the motivational function of the motor response. (shrink)

A quintessential challenge for any perceptual system is the need to focus on task-relevant information without being blindsided by unexpected, yet important information. The human visual system incorporates several solutions to this challenge, one of which is a reflexive covert attention system that is rapidly responsive to both the physical salience and the task-relevance of new information. This paper presents a model that simulates behavioral and neural correlates of reflexive attention as the product of brief neural attractor states that (...) are formed across the visual hierarchy when attention is engaged. Such attractors emerge from an attentional gradient distributed over a population of topographically organized neurons and serve to focus processing at one or more locations in the visual field, while inhibiting the processing of lower priority information. The model moves towards a resolution of key debates about the nature of reflexive attention, such as whether it is parallel or serial, and whether suppression effects are distributed in a spatial surround, or selectively at the location of distractors. Most importantly, the model develops a framework for understanding the neural mechanisms of visual attention as a spatiotopic decision process within a hierarchy and links them to observable correlates such as accuracy, reaction time, and the N2pc and PD components of the EEG. This last contribution is the most crucial for repairing the disconnect that exists between our understanding of behavioral and neural correlates of attention. (shrink)

In the sacrificial moral dilemma task, participants have to morally judge an action that saves several lives at the cost of killing one person. According to the dual process corrective model of moral judgment suggested by Greene and collaborators (2001; 2004; 2008), cognitive control is necessary to override the intuitive, deontological force of the norm against killing and endorse the utilitarian perspective. However, a conflict model has been proposed more recently to account for part of the evidence in favor of (...) dual process models in moral and social decision making. In this model, conflict, moral responses and reaction times arise from the interplay between individually variable motivational factors and objective parameters intrinsic to the choices offered. To further explore this model in the moral dilemma task, we confronted three different samples with a set of dilemmas representing an objective gradient of utilitarian pull, and collected data on moral judgment and on conflict in a 4-point scale. Collapsing all cases along the gradient, participants in each sample felt less conflicted on average when they gave extreme responses (1 or 4 in the UR scale). They felt less conflicted on average when responding to either the low- or the high-pull cases. The correlation between utilitarian responses and conflict was positive in the low-pull and negative in the high-pull cases. This pattern of data suggests that moral responses to sacrificial dilemmas are driven by decision conflict, which in turn depends on the interplay between an objective gradient of utilitarian pull and the moral motivations which regulate individual responsiveness to this gradient. (shrink)

Although the existence of implicit motor learning is now widely accepted, the findings concerning perceptual implicit learning are ambiguous. Some researchers have observed perceptual learning whereas other authors have not. The review of the literature provides different reasons to explain this ambiguous picture, such as differences in the underlying learning processes, selective attention, or differences in the difficulty to express this knowledge. In three experiments, we investigated implicit visual learning within the original serial reaction time task. We (...) used different response devices in order to manipulate selective attention towards response dimensions. Results showed that visual and motor sequence learning differed in terms of RT-benefits, but not in terms of the amount of knowledge assessed after training. Furthermore, visual sequence learning was modulated by selective attention. However, the findings of all three experiments suggest that selective attention did not alter implicit but rather explicit learning processes. (shrink)

To further develop three-dimensional (3D) applications, it is important to elucidate the negative effects of 3D applications on the human body and mind. Thus, this study investigated differences in the effects of visual fatigue on cognition and brain activity using visual and auditory tasks induced by watching a 1-h movie in two dimensions (2D) and 3D. Eighteen young men participated in this study. Two conditions were randomly performed for each participant on different days, namely, watching the 1-h movie (...) on television in 2D (control condition) and 3D (3D condition). Before and after watching the 1-h movie on television, critical flicker fusion frequency (CFF: an index of visual fatigue), and response accuracy and reaction time for the cognitive tasks were determined. Brain activity during the cognitive tasks was evaluated using a multi-channel near-infrared spectroscopy system. In contrast to the control condition, the decreased CFF, and the lengthened reaction time and the decreased activity around the right primary somatosensory cortex during Go/NoGo blocks in the visual task at post-viewing in the 3D condition were significant, with significant repeated measures correlations among them. Meanwhile, in the auditory task, the changes in cognitive performance and brain activity during the Go/NoGo blocks were not significant in the 3D condition. These results suggest that the failure or delay in the transmission of visual information to the primary somatosensory cortex due to visual fatigue induced by watching a 3D movie reduced the brain activity around the primary somatosensory cortex, resulting in poor cognitive performance for the visual task. This suggests that performing tasks that require visual information, such as running in the dark or driving a car, immediately after using a 3D application, may create unexpected risks in our lives. Thus, the findings of this study will help outlining precautions for the use of 3D applications. (shrink)

The pupils of the eyes reflexively constrict in light and dilate in dark to optimize retinal illumination. Non-visual cognitive factors, like attention, arousal, decision-making, etc., also influence pupillary light response. During passive viewing, the eccentricity of a stimulus modulates the pupillary aperture size driven by spatially weighted corneal flux density, which is the product of luminance and the area of the stimulus. Whether the scope of attention also influences PLR remains unclear. In this study, we contrasted the pupil (...) dynamics between diffused and focused attentional conditions during decision-making, while the global CFD remained the same in the two conditions. A population of 20 healthy humans participated in a pair of forced choice tasks. They distributed attention to the peripheral decision cue in one task, and concentrated at the center in the other to select the target from four alternatives for gaze orientation. The location of this cue did not influence participants’ reaction time. However, the magnitude of constriction was significantly less in the task that warranted attention to be deployed at the center than on the periphery. We observed similar pupil dynamics when participants either elicited or canceled a saccadic eye movement, which ruled out pre-saccadic obligatory attentional orientation contributing to PLR. We further addressed how the location of attentional deployment might have influenced PLR. We simulated a biomechanical model of PLR with visual stimulation of different strengths as inputs corresponding to the two attentional conditions. In this homeomorphic model, the computational characteristic of each element was derived from the physiological and/or mechanical properties of the corresponding biological element. The simulation of this model successfully mimicked the observed data. In contrast to common belief that the global ambient luminosity drives pupillary response, the results of our study suggest that the effective CFD determined via the luminance multiplied by the size of the stimulus at the location of deployed attention in the visual space is critical for the magnitude of pupillary constriction. (shrink)

ABSTRACTIn the present study, attentional bias was investigated as a potential predisposing mechanism for the contamination-related subtype of obsessive-compulsive disorder. Fifty healthy participants with varying degrees of subclinical C-OC symptoms performed a visual search task to measure differential attentional biases elicited by neutral, disgust-, and fear-specific pictorial material. Participants had to find a target picture within five neutral distractor pictures randomly presented on different locations in an array. The task was to decide whether the array contained an unpleasant target (...) picture or not. In randomly-selected emotional trials, participants were further asked about the content of the picture and the confidence of their answer. The results show that the reaction times significantly differed between the emotional and neutral pictures. Participants were significantly more confident in answering questions referring to fear compared to disgust pictures. This effect was mar... (shrink)

Choice reaction times to visual stimuli may be influenced by preceding subliminal stimuli . Some authors reported a straight priming effect i.e., responses were faster when primes and targets called for the same response than when they called for different responses. Others found the reversed pattern of results. Eimer and Schlaghecken [Eimer, M. & Schlaghecken, F. . Links between conscious awareness and response inhibition: evidence from masked priming. Psychonomic Bulletin & Review, 9, 514–520.] showed recently that (...) straight priming occurs whenever a prime is not efficiently masked thereby the information provided by the prime is accessible for consciousness. In the present study, a hypothesis is tested that straight priming is due to mediation of consciousness. To test this hypothesis, prime validity was manipulated. We showed that even when no mask was used so that participants could fully and consciously perceive the prime and participants were informed that primes were mostly invalid, for the short prime–target ISI interval straight priming occurred. The priming was inverse when the ISI was 800 ms. This indicates that participants were able to use the information provided by the prime to prepare the response opposite to that cued by the prime but only if the time between the prime and the target was long enough. (shrink)

This study investigated the effect of obstructive sleep apnea on the neural mechanism of visual perception. A preliminary case-control study was conducted. Seventeen patients with moderate to severe OSA in the sleep center of Civil Aviation General Hospital and 20 healthy controls matched for age, sex, and education were recruited. The participants accepted the perceptual contour integration task, compared the differences in behavioral indicators between the two groups, and compared the differences in electroencephalography data between the two groups through (...) event-related potential technology. The groups did not differ significantly in age and gender, but they differed significantly in body mass index. The groups were not statistically different in terms of sleep structure and total sleep time. AHI, sleep efficiency, and minimal SaO2 value in the OSA group were significantly different from those of the control group. The results showed that the average reaction time of the OSA group was significantly longer than that of the healthy control group in the contour integration task. There was no significant difference in the accuracy rate. The results of EEG showed that the amplitudes of N100 of the OSA group were significantly higher than those of the control group at O1, Oz, and O2 electrodes. There was no significant difference in latency between the two groups. At the FCz electrode, the amplitudes of N200 of the OSA group were significantly higher than those of the control group. Therefore, we concluded that in the early stage of the perceptual integration task, although the neural response activity of patients with moderate and severe OSA was not accelerated, they need to call on more psychological resources, activate more neurons in the contour global recognition processing stage, and the compensatory effect of frontal lobe appeared in the stage of visual perception. (shrink)

Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right-hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand (...) advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked directly to specialized functions of the right hemisphere: bisecting, the gap effect, and visuospatial localization. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one-dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests. (shrink)

Matching bias refers to the non-normative performance that occurs when elements mentioned in a rule do not correspond with those in a test item. One aim of the present work is to capture matching bias via reaction times as participants carry out truth-table evaluation tasks. Experiment 1 requires participants to verify conditional rules, and Experiment 2 to falsify them as the paradigm employs four types of conditional sentences that systematically rotate negatives in the antecedent and consequent; and presents predominantly (...) cases having true antecedents. These experiments reveal that mismatching is linked to higher rates of incorrect responses and slower evaluation times. A second aim is to investigate the way not is processed. We compare a narrow view of negations, which argues that negation only denies information, to a search for alternatives view, which says that negations function to prime appropriate alternatives. Findings from both experiments support a narrow reading view. (shrink)

Evidence is summarised for and against the hypothesis that potentiation or facilitation of neural responses during a train of threshold-level stimuli occurred in the experiments reported by Libet et al. . It is concluded that such potentiation probably did occur. Since the main arguments for the existence of subjective backwards referral take it as given that such potentiation did not occur, it is further concluded that the main arguments for the existence of subjective backwards referral fail.