Choice Reaction Time Experiments Research Articles

Kualitas Tidur Buruk Memperlambat Waktu Reaksi Visual pada Mahasiswa Program Studi Sarjana Fisioterapi Fakultas Kedokteran Universitas Udayana

Background: College students are one of the groups that have a high risk of experiencing sleep deprivation and sleep disorders. In medical students, this is due to the high duration and intensity of education. Poor sleep quality causes impaired cognitive function, one of which is decreased reaction time. Students with faster reaction times have better cognitive status and academic performance. This study aims to determine how the relationship of sleep quality to reaction time with the type of simple reaction time (SRT) and choice reaction time (CRT) experiment in physiotherapy student at faculty of medicine, university of udayana.Methods: The cross-sectional study was conducted with simple random sampling technique. 45 students participated in this study. Sleep quality was measured with Pittsburgh Sleep Quality Index (PSQI) and reaction time using Deary-Liewald reaction time task with SRT and CRT types of experiment. Bivariate analysis was performed using the Spearman rho test.Result: 21 people (46.7%) had good sleep quality and 24 people (53.3%) had poor sleep quality. The results showed that there was a relationship between sleep quality and reaction time using CRT (p = 0.003) and there was no relationship between sleep quality and reaction time using SRT (p = 0.084).Conclusion: Poor sleep quality resulted in decreased reaction time with the CRT experiment type. The authors suggests research with different methods and populations, also add more control variables.

Representation of Perceptual Evidence in the Human Brain Assessed by Fast, Within-Trial Dynamic Stimuli.

In perceptual decision making the brain extracts and accumulates decision evidence from a stimulus over time and eventually makes a decision based on the accumulated evidence. Several characteristics of this process have been observed in human electrophysiological experiments, especially an average build-up of motor-related signals supposedly reflecting accumulated evidence, when averaged across trials. Another recently established approach to investigate the representation of decision evidence in brain signals is to correlate the within-trial fluctuations of decision evidence with the measured signals. We here report results of this approach for a two-alternative forced choice reaction time experiment measured using magnetoencephalography (MEG) recordings. Our results show: (1) that decision evidence is most strongly represented in the MEG signals in three consecutive phases and (2) that posterior cingulate cortex is involved most consistently, among all brain areas, in all three of the identified phases. As most previous work on perceptual decision making in the brain has focused on parietal and motor areas, our findings therefore suggest that the role of the posterior cingulate cortex in perceptual decision making may be currently underestimated.

The contribution of stimulus frequency and recency to set-size effects

Hick’s law describes the increase in choice reaction time (RT) with the number of stimulus-response (S-R) mappings. However, in choice RT experiments, set-size is typically confounded with stimulus recency and frequency: With a smaller set-size, each stimulus occurs on average more frequently and more recently than with a larger set-size. To determine to what extent stimulus recency and frequency contribute to the set-size effect, stimulus set-size was manipulated independently of stimulus recency and frequency, by keeping recency and frequency constant for a subset of the stimuli. Although this substantially reduced the set-size effect (by approximately two-thirds for these stimuli), it did not eliminate it. Thus, the time required to retrieve an S-R mapping from memory is (at least in part) determined by the number of alternatives. In contrast, a recent task switching study (Van ‘t Wout et al. in Journal of Experimental Psychology: Learning, Memory & Cognition., 41, 363–376, 2015) using the same manipulation found that the time required to retrieve a task-set from memory is not influenced by the number of alternatives per se. Hence, this experiment further supports a distinction between two levels of representation in task-set control: The level of task-sets, and the level of S-R mappings.

Factoring out nondecision time in choice reaction time data: Theory and implications.

Choice reaction time (RT) experiments are an invaluable tool in psychology and neuroscience. A common assumption is that the total choice response time is the sum of a decision and a nondecision part (time spent on perceptual and motor processes). While the decision part is typically modeled very carefully (commonly with diffusion models), a simple and ad hoc distribution (mostly uniform) is assumed for the nondecision component. Nevertheless, it has been shown that the misspecification of the nondecision time can severely distort the decision model parameter estimates. In this article, we propose an alternative approach to the estimation of choice RT models that elegantly bypasses the specification of the nondecision time distribution by means of an unconventional convolution of data and decision model distributions (hence called the D*M approach). Once the decision model parameters have been estimated, it is possible to compute a nonparametric estimate of the nondecision time distribution. The technique is tested on simulated data, and is shown to systematically remove traditional estimation bias related to misspecified nondecision time, even for a relatively small number of observations. The shape of the actual underlying nondecision time distribution can also be recovered. Next, the D*M approach is applied to a selection of existing diffusion model application articles. For all of these studies, substantial quantitative differences with the original analyses are found. For one study, these differences radically alter its final conclusions, underlining the importance of our approach. Additionally, we find that strongly right skewed nondecision time distributions are not at all uncommon.

Click trains and the rate of information processing: Does “speeding up” subjective time make other psychological processes run faster?

A series of experiments demonstrated that a 5-s train of clicks that have been shown in previous studies to increase the subjective duration of tones they precede (in a manner consistent with "speeding up" timing processes) could also have an effect on information-processing rate. Experiments used studies of simple and choice reaction time (Experiment 1), or mental arithmetic (Experiment 2). In general, preceding trials by clicks made response times significantly shorter than those for trials without clicks, but white noise had no effects on response times. Experiments 3 and 4 investigated the effects of clicks on performance on memory tasks, using variants of two classic experiments of cognitive psychology: Sperling's (1960) iconic memory task and Loftus, Johnson, and Shimamura's (1985) iconic masking task. In both experiments participants were able to recall or recognize significantly more information from stimuli preceded by clicks than those preceded by silence.

Processing time predictions of current models of perception in the classic additive factors paradigm

This article explores the consequences for factorial additivity in a Sternberg [(1969). The discovery of processing stages: Extensions of donders method In: W.G. Koster (Ed.), Attention and performance II, Acta Psychologica, 30, 276–315] additive-factors paradigm of the assumptions adopted by models of perception that relate the representation of a stimulus to decision time. Three example models, signal detection theory with the latency-distance hypothesis, stochastic general recognition theory, and a random walk model of exemplar classification, are interrogated to determine what type of interaction they predict factors will yield in a hypothetical factorial (choice) reaction time experiment in which the ‘empirical’ factors’ effects are manifest as parameter changes. All frameworks make the critical assumption that decision time depends on the perceptual representation of the stimulus as well as the architecture. As a consequence, nonadditivity of factors thought to affect different “stages” in the classical approach emerges within the current modeling approach. The nature of this influence is revealed through analytic investigations and simulation. Earlier empirical findings of failures of selective influence that have defied adequate explanation are reinterpreted in light of the present findings.

Simon congruency effects based on stimulus and response numerosity

Three choice reaction time experiments documented a Simon-type congruence effect involving the numbers of stimuli and responses. In Experiment 1 the stimulus consisted of one or two high- or low-pitch tones, and participants were required to respond with one or two taps of a response key depending on stimulus pitch. Responses were faster when the number of tones matched the required number of response taps than when these numbers mismatched. Experiment 2 showed that a weaker version of this effect can also be obtained using visual stimuli, and Experiment 3 showed that the analogous effect can even be obtained, albeit very weakly, with bimodal stimuli. There was also evidence that the number of stimuli affected the rate of emitting the two-tap response. These results indicate that stimulus numerosity is processed automatically to the level at which it can affect the selection and possibly the execution of a varying number of responses.

Compatibility effects based on stimulus and response numerosity

Four choice reaction time experiments documented a stimulus-response (S-R) compatibility effect involving the numbers of stimuli and responses. In Experiment 1, the stimulus consisted of one or two tones, and the correct response was either one or two taps of a response key. Responses were much faster with a compatible S-R assignment, in which the number of taps matched the number of tones, than with an incompatible assignment in which these numbers mismatched. Experiments 2 and 3 replicated this effect, using visual stimuli and bimodal stimuli, respectively, suggesting that auditory/manual rhythmic compatibility is not essential to it. Experiment 4 showed that an analogous but smaller effect is obtained when stimuli are the digits 1 and 2. This new numerosity-based compatibility effect has general theoretical implications regarding the mechanisms responsible for compatibility effects and practical implications for interface design.

Abnormal Brain Activity Related to Performance Monitoring and Error Detection in Children with ADHD

Brain electrical activity associated with inhibitory control was recorded in ten ADHD and ten healthy children using high density event related potentials (ERPs) during the Stop Signal Task (SST). SST is a two-choice reaction time (RT) paradigm, in which subjects are required, on 25% of the trials, to withdraw their response upon presentation of a “Stop Signal”. In the healthy children, the ERP evoked by the Stop Signal differed for successful inhibitions (SI) compared to failed inhibitions (FI), with greater amplitude of a positive wave peaking around 320 msec over anterior medial frontal scalp (P3a). Such success-related P3a activity was significantly reduced in amplitude in the ADHD group. In addition, the error related negativity (ERN), a sharp negative wave that is present selectively on error trials in choice RT experiments, peaking 100 ms after motor onset, and distributed over anterior medial frontal scalp, was also markedly reduced in the ADHD group. The scalp distribution of the group differences in P3a and the ERN is consistent with a reduction of activity of sources in dorsal anterior cingulate cortex (dACC), suggesting a global deficit in cognitive control operations subserved by dACC in ADHD.

Error-Related Brain Activity in Patients with Obsessive- Compulsive Disorder and in Healthy Controls

Abstract: Obsessive-compulsive disorder (OCD) has been related to a hyperactive frontal-striatal-thalamic circuit and associated with altered mechanisms of action and error monitoring. In the present study, we examined whether these results only hold for errors in choice reaction time experiments and Stroop tasks or extend to errors of commission in a Go/NoGo task, as well. We investigated the electrophysiological correlates of error monitoring in 11 patients with OCD and 11 age-, sex-, and education-matched healthy controls using event-related potentials (ERPs). Participants performed a Go/NoGo task while a 64-channel EEG was recorded. Our study focused on three ERP components: the error-related negativity (ERN)/error negativity (Ne), the “early” error positivity (“early” Pe) reflecting automatic error processing, and the “late” error positivity (“late” Pe), which is thought to mirror the awareness of erroneous responses. Artifact-free EEG-segments were used to compute ERPs on correct Go trials and incorrect NoGo trials (i.e., errors of commission), separately. Patients with OCD showed enhanced (more negative) ERN/Ne amplitudes compared to control subjects. Groups did not differ with regard to the early Pe component and the late Pe component. Our results support the view that compulsivity in OCD patients is related to hyper-functioning error monitoring processes.

Evidence for a close relationship between conscious effort and anterior cingulate cortex activity

The function of the anterior cingulate cortex (ACC) has been discussed in the last years in the context of conflict monitoring and error detection. In addition, ACC activity has been described in the context of “conscious effort”. Recent neurophysiological and neuroimaging studies have described a negative correlation between ACC activity and reaction times in simple or choice reaction time experiments. One suggested explanation for this finding has been that there is a relationship between effort and ACC activity. The present ERP-LORETA study of healthy volunteers ( n=35) was intended to directly investigate this relationship. In this experiment, three conditions were investigated: condition I was a choice reaction task with the instruction to stay relaxed during the task (relaxed condition), condition II was the same choice reaction task with the instruction to press the respective button as fast and correct as possible (effort condition). Condition III was just listening to the tones without button press (control condition). Subjects had to score directly after each experimental run on a visual analogue scale the amount of effort they have actually spent. The subjects showed significantly shorter reaction times during the high effort condition in comparison to the relaxed condition, as well as increased N1 amplitudes and increased ACC activity. In a subgroup analysis, this effect was present only in subjects who were (according to their self-ratings) following the instructions closely. These results provide direct evidence for a close relationship between conscious effort and ACC activity and suggest the usefulness of the applied effort-self-rating.

Discrepant target detection and action monitoring in obsessive–compulsive disorder

Obsessive–compulsive disorder (OCD) has been related to altered mechanisms of action monitoring and target detection, and it has been hypothesized that hyperactive striatal–cortical circuits constitute the underlying pathophysiology. This study used event-related brain potentials (ERPs) to explore this hypothesis. A choice reaction time experiment was carried out in a group of OCD patients and a normal comparison group. The P3b component of the ERP to targets was taken as an indicator of the target-evaluation process and the response-locked error-related negativity (ERN) served as an indicator of action monitoring. We hypothesized that the OCD group would show a shortened P3b latency and an amplitude-enhanced ERN. Consistent with our expectations, the P3b latency was shorter and the ERN amplitude was higher in the OCD group. Unexpectedly, we also observed a prolonged ERN latency in the OCD group and a more posterior topography of this component. The data provide partial support for the hypothesis of a hyperactive neural network in OCD. In addition the disorder must involve pathophysiological processes that are presumably related to other aspects of its complex and heterogeneous clinical hallmarks.

Timing and reaction time.

Because reaction time (RT) tasks are generally repetitive and temporally regular, participants may use timing strategies that affect response speed and accuracy. This hypothesis was tested in 3 serial choice RT experiments in which participants were presented with stimuli that sometimes arrived earlier or later than normal. RTs increased and errors decreased when stimuli came earlier than normal, and RTs decreased and errors increased when stimuli came later than normal. The results were consistent with an elaboration of R. Ratcliff's diffusion model (R. Ratcliff, 1978; R. Ratcliff & J. N. Rouder, 1998; R. Ratcliff, T. Van Zandt, & G. McKoon, 1999), supplemented by a hypothesis developed by D. Laming (1979a, 1979b), according to which participants initiate stimulus sampling before the onset of the stimulus at a time governed by an internal timekeeper. The success of this model suggests that timing is used in the service of decision making.

Timing and reaction time.

Because reaction time (RT) tasks are generally repetitive and temporally regular, participants may use timing strategies that affect response speed and accuracy. This hypothesis was tested in 3 serial choice RT experiments in which participants were presented with stimuli that sometimes arrived earlier or later than normal. RTs increased and errors decreased when stimuli came earlier than normal, and RTs decreased and errors increased when stimuli came later than normal. The results were consistent with an elaboration of R. Ratcliff's diffusion model (R. Ratcliff, 1978; R. Ratcliff & J. N. Rouder, 1998; R. Ratcliff, T. Van Zandt, & G. McKoon, 1999), supplemented by a hypothesis developed by D. Laming (1979a, 1979b), according to which participants initiate stimulus sampling before the onset of the stimulus at a time governed by an internal timekeeper. The success of this model suggests that timing is used in the service of decision making.

Serotonin and human information processing: an electromyographic study of the effects of fluvoxamine on choice reaction time

Previous studies have shown that fluvoxamine, an inhibitor of serotonin reuptake, shortens choice reaction time. The present study, was intended to explore this effect by using two complementary approaches: (i) Sternberg's additive factor method, and (ii) the analysis of the electromyographic activity of a prime mover. Eight healthy subjects who received either a single oral dose of fluvoxamine (100 mg) or a placebo participated in a choice reaction time experiment in which imperative signal intensity, stimulus-response mapping, and response repertoire were manipulated. Previous results were replicated. Moreover, it was shown that fluvoxamine shortens the interval between prime mover activation and overt response. This supports the hypothesis proposed in a previous study that fluvoxamine affects motor processes. A possible mechanism of this effect is discussed.

Stimulus-Response Compatibility Is Information-Action Compatibility

Stimulus-response compatibility experiments usually employ simple stimuli (e.g., colored lights) and simple responses (e.g., keypresses). The ecological approach to perception and action, on the other hand, emphasizes higher order quantities, information, and action. The three choice reaction time experiments reported here demonstrate the utility of the higher order descriptors for understanding compatibility effects. In Experiment 1, proximal-distal responses were shown to be compatible with the approach-withdrawal information embodied in a two-dimensional kinematic pattern. In Experiment 2, compatibility effects reflected unique combinations of stimulus location, geometric information about distance, and the response. In Experi- ment 3, a compatibility effect was shown to be a function of an action rather than a mere movement. These results favor an informational description of stimuli and emphasize the functional significance of responses.

The ‘oddball CNV’ as an indicator of different information processing in patients with panic disorders

In previous studies we found an inverse relationship between CNV amplitude and the probability of the occurrence of the warning stimulus (S1) in a cued reaction time task. The aim of the present study was to investigate this ‘oddball effect’ on CNV amplitude (Oddball CNV) in patients with anxiety disorders, since this effect describes the influence of event probability on reactive as well as proactive components of information processing. Patients suffering from panic disorders with or without agoraphobia and controls participated in a choice reaction time experiment. The subjects' task was to respond to flashes (S2s), cued 4 s in advance in random order by one of two easily distinguishable acoustic stimuli (Sta, S1b). In condition 1 the probability of S1a and S1b was 0.2 and 0.8, respectively, and in condition 2 0.5 for both S1s. The DC-EEG was recorded from F 3, F 4, C 3, C z, C 4 and P 3, linked mastoids as the reference. The data obtained confirm the oddball effect on the CNV amplitude, show clear deviations of patients in this effect, and also indicate remarkable differences in CNV shape between patients and controls. These observations are discussed as differences in information processing and information utilization.

Re-orientation of attention in Parkinson's disease: An extension to the vibrotactile modality

Parkinson's disease (PD), a disorder of the dopaminergic nigro-striatal pathway, is associated with both motor and cognitive impairments, including perhaps the ability to focus attention. Disturbances of attentional processes were further examined in a series of vibrotactile choice reaction time (cRT) experiments involving biased probabilities of event occurrence, or valid/invalid precueing. Results of three experiments suggest that PD subjects, compared to controls, are less adept at maintaining attention in space. The performance of the PD subjects improved, however, when they were permitted to direct their gaze to one hand or the other, and when valid external precues were provided before each trial. Observed similarities between the cognitive and motor deficits of PD subjects support the notion that there is a close coupling between the mechanisms coordinating attention and movement.

The spatial distribution of attention in S-R compatibility

In certain choice reaction time experiments the subjects, although not specifically instructed to do so, perform a parcellation of space into right and left components. Previous research has shown that when the stimulus locations are marked on the screen, the subdivision of space into right and left halves is bound to the point where the subject has been instructed to focus selective attention. It is not known whether, in the absence of specific instructions, subjects are able to focus selective attention between stimulus locations when no marker is present. We tried to clarify this problem by introducing a 'probe' stimulus that could map the spatial distribution of attention in subjects engaged in a compatibility task. The results suggest that, in the absence of visual cues marking the stimulus positions, attention is kept in the disengaged modality before the presentation of the stimuli. In this state of disengagement a powerful tendency to orient to the rightmost side of the display, within each visual field, is apparent. Various interpretations of this finding are discussed.

Redundancy phenomena are affected by response requirements

Results are reported for two go/no-go reaction time (RT) experiments, in which the redundant targets advantage was investigated. These experiments were replications of two earlier choice reaction time (CRT) experiments, in which letter stimuli were used. Important differences between the go/no-go RT experiments and the CRT experiments were obtained. Equal and significant redundancy advantages were obtained whether redundant targets were compared with a single target presented with a noise letter or without noise. In the CRT experiments, the advantage was not obtained in the comparison with a single target presented alone. Noise letters did not slow the RTs to single targets with which they were presented as was the case with CRT. Since the differing results of the two procedures depend on the response requirements, explanation of differing CRT data in terms of perceptual or attentional concepts is probably inappropriate. The presence and absence of response competition in the two situations may be the best interpretation. The results tend to support a conclusion of the parallel processing of two letter stimuli separated spatially by as much as 3 degrees.