Automatic processing of psychological distance: evidence from a Stroop task

A picture-word version of the Stroop task was used to test the automatic activation of psychological distance by words carrying various senses of psychological distance: temporal (tomorrow, in a year), social (friend, enemy), and hypotheticality (sure, maybe). The pictures implied depth, with the words appearing relatively close to or distant from the observer. The participants classified the spatial distance of words faster when the word's implicit psychological distance matched its spatial distance (e.g., a geographically close word was classified faster when it was "friend" than when it was "enemy"). The findings are consistent with the idea that psychological distance is accessed automatically, even when it is not directly related to people's current goals, and suggest that psychological distance is an important dimension of meaning, common to spatial distance, temporal distance, social distance, and hypotheticality.     

One night of sleep deprivation affects reaction time, but not interference or facilitation in a Stroop task

The Stroop color-naming task is one of the most widely studied tasks involving the inhibition of a prepotent response, regarded as an executive function. Several studies have examined performance on versions of the Stroop task under conditions of acute sleep deprivation. Though these studies revealed effects on Stroop performance, the results often do not differentiate between general effects of sleep deprivation on performance and effects specifically on interference in the Stroop task. To examine the effect of prolonged wakefulness on performance on the Stroop task, we studied participants in a 40-h "constant routine" protocol during which they remained awake in constant conditions and performed a Stroop color-naming task every two hours. We found that reaction time was slowest when the color and word did not match (incongruent), fastest when the color and word did match (congruent), and intermediate when participants named the color of the non-word stimulus (neutral). Performance on all three trial types degraded significantly as a function of time awake. Extended wakefulness did not significantly change the additional time needed to respond when the color and word did not match (Stroop interference), nor did it change the amount of facilitation when color and word matched. These results indicate that one night of sleep deprivation influences performance on the Stroop task by an overall increase in response time, but does not appear to impact the underlying processes of interference or facilitation. The results suggest that the degree to which an "executive function" is affected by sleep deprivation may depend on the particular executive function studied and the degree to which it is subserved by the prefrontal cortex.     

Cardiac activity in a simple reaction time task

Twenty subjects, half having high extraversion and the other half having low extraversion scores on the Eysenck Personality Inventory, performed a simple reaction time task in which the warning stimulus was a light and the imperative stimulus was a tone. Beat-by-beat analysis showed significantly different response patterns between the two groups in time of onset, magnitude, and duration of the cardiac responses. The extraversion measures were found to relate to central-nervous-system-strength types and to indicate relative strength of central inhibitory processes, as reflected by cardiac activity.     

Conceptual response distance and intervening keys distinguish action goals in the Stroop color-identification task

In previous studies, a physical response-distance effect was found in the two-choice Stroop color-identification task, with the Stroop effect being larger when the two response keys were physically close together than when they were far apart. In the present study, we found a conceptual response-distance effect, with the Stroop effect being larger when the response keys were conceptually close (labeled as “5” and “6”) than when they were conceptually far (labeled as “1” and “9”). Moreover, a response-distance effect due to pure physical distance was not evident; rather, the effect was found only when additional keys were placed between the two far response keys. These results are in agreement with a view that response keys are coded as action goals, with farther conceptual distance and additional keys helping distinguish the action goals. The results are difficult to reconcile with accounts that place emphasis on the physical separation of the effectors or their inanimate extensions.     

Initiation of bilateral responses in a kinesthetic reaction time task

Two experiments are presented in which different mechanisms controlling each limb in a bilateral arm response to a unilateral kinesthetic stimulus are postulated to occur. In Experiment 1, the limb serving as the stimulus are postulated to occur. In Experiment 1, the limb serving as the stimulus limb was described as operating with relative invariance by using a tightly coupled input-output reflexive pathway, whereas the nonstimulus limb appeared to be controlled by higher-order processing thought to be more susceptible to influences such as hemispheric specialization and stimulus expectancy. The differential control model was further tested in Experiment 2 by retaining the interhemispheric pathway of the unilateral kinesthetic stimulus but experimentally uncoupling the reflex mechanism from the stimulus side. Analyses of bilateral EMG premotor latencies under these conditions revealed that each response side can be controlled at separate levels-i.e., by a reflexive type mechanism or by higher-order processing when one of the response limbs is also the stimulus limb, both sides reflect behavior that is best described by an information processing type of voluntary control.     

Effector-related sequence learning in a bimanual-bisequential serial reaction time task

In a bimanual-bisequential version of the serial reaction time (SRT) task participants performed two uncorrelated key-press sequences simultaneously, one with fingers of the left hand and the other with fingers of the right hand. Participants responded to location-based imperative stimuli. When two such stimuli appeared in each trial, the results suggest independent learning of the two sequences and the occurrence of intermanual transfer. Following extended practice in Experiment 2, transfer of acquired sequence knowledge was not complete. Also in Experiment 2, when only one stimulus appeared in each trial specifying the responses for both hands so that there was no basis for separate stimulus-stimulus or separate response-effect learning, independent sequence learning was again evident, but there was no intermanual transfer at all. These findings suggest the existence of two mechanisms of sequence learning, one hand-related stimulus-based and the other motor-based, with only the former allowing for intermanual transfer.     

Sentence interference in the Stroop task

In two experiments on Stroop interference, we examined whether sentences can be processed without the intention of the reader. Participants named the ink colors in which words in sentences were printed, and the ink colors in which the same words, randomly arranged, were printed. In Experiment 1, sentences yielded longer response times (RTs) and more errors than did nonsentences, but only when they included words that were highly relevant to the color-naming task (i.e., color and color-related words). In Experiment 2, sentences yielded more errors than did nonsentences, and sentences in which the color words matched the set of ink colors yielded longer RTs than did nonsentences. The results indicate that sentence processing can be obligatory when the component words are highly relevant to the task.     

Investigating hemispheric specialization in a novel face-word Stroop task

We examined hemispheric specialization in a lateralized Stroop facial identification task. A 2 (presentation side: left or right visual field [LVF or RVF])x2 (picture emotion: happy or angry)x3 (emotion of distractor word: happy, angry, or blank) factorial design placed the right hemispheric specialization for emotional expression processing and the left hemispheric specialization for verbal processing in conflict. Faces (from ) and emotion words were briefly displayed, and participants responded with keypresses corresponding to the picture emotion. As predicted, greater Stroop interference in identification accuracy was found with incongruent displays of facial expression in the LVF and emotion words in the RVF, and females exhibited less Stroop interference. Reaction times were moderated by emotion and visual field.     

Effects of stimulus probability on reaction time in a number-naming task

Subjects were required to respond to the visual presentation of numerals by uttering syllables closely resembling the names of the numerals. Information in stimulus ensembles was varied by manipulating the number of alternative stimulus configurations that could appear, the relative frequencies of stimuli within an ensemble and the probability of a response being required. An increasing linear function was a good first approximation to the relation between reaction time and information transmission. Systematic deviations from this function were found and an attempt is made to explain them by introducing an intervening variable, “effective probability.”     

The influence of response-effect compatibility in a serial reaction time task

Participants performed a serial reaction time task, responding to either asterisks presented at varying screen locations or centrally presented letters. Stimulus presentation followed a fixed second-order conditional sequence. Each keypress in the experimental groups produced a contingent, key-specific tone effect. The critical variation concerned the mapping of tones to keys. In Experiment 1, keypresses in one control condition produced noncontingent tone effects, while in another control condition there were no tone effects. In Experiment 2, three different key-tone mappings were compared to a control condition without tone effects. The results show that tone effects improve serial learning when they are mapped to the response keys contingently and in a highly compatible manner. The results are discussed with reference to an ideomotor mechanism of motor sequence acquisition.     

Competition between rhythmic and linguistic organization in a sentence-rhythm Stroop task

We provide a test of Patel's [(2003 Patel, A. D. (2003). Language, music, syntax and the brain. Nature Neuroscience, 6, 674–681. doi: 10.1038/nn1082[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). Language, music, syntax and the brain. Nature Neuroscience, 6, 674–681] shared syntactic integration resources hypothesis by investigating the competition between determinants of rhythmic parsing and linguistic parsing using a sentence-rhythm Stroop task. We played five-note rhythm patterns in which each note is replaced with a spoken word of a five-word sentence and asked participants to indicate the starting point of the rhythm while they disregarded which word would normally be heard as the first word of the sentence. In Study 1, listeners completed the task in their native language. In Study 2, we investigated whether this competition is weakened if the sentences were in a listener's non-native language. In Study 3, we investigated how much language mastery is necessary to obtain the effects seen in Studies 1 and 2. We demonstrate that processing resources for rhythmic parsing and linguistic parsing overlap with one another, particularly when the task is demanding. We also show that the tendency for language to bias processing does not require deep knowledge of the language.     

Performance on a simple reaction time task while sleep deprived

Divergent results have been reported on the effect of a night's sleep loss on performance of a single monotonous task. The present experiment examined the effect that partial sleep deprivation had on 10 participants' performance on a simple reaction time task requiring low responding for 120 min. compared to performance on the same task when well rested. Participants missed significantly more signals and had slower reaction times when sleep deprived. Reaction times increased with time when participants were both sleep deprived and rested, but the number of misses did not significantly change over time. Reaction time was significantly correlated with subjective ratings of sleepiness and heart rate in both conditions. EEG and heart-rate variability measures did not correlate significantly with reaction time. Misses correlated significantly with subjective ratings and heart rate but only in the rested condition.     

Assessment of sexual preference using a choice reaction time task

The purpose of this study was to investigate the use of a choice reaction time task, during which slides of sexually explicit and neutral stimuli were used as an interference task, to differentiate between groups of individuals on the basis of their sexual preference. Twenty subjects, in each of the four groups (heterosexual males, heterosexual females, homosexual males, and homosexual females), participated in this study. Sexual orientation was determined by self-report. Subjects were given a choice reaction time with interference task, followed by a recall incidental learning task. A significant higher-order interaction was found among gender, orientation, and stimulus type for all four groups. This interaction indicated a longer reaction time to slides depicting preferred sexual partners than to nonpreferred sexual partners or neutral scenes. These results indicate that sexual arousal does interfere with cognitive processing. A main effect for gender was found for the incidental learning task, with males having the fewest errors.     

Attention,spatial integration,and the tail of response time distributions in Stroop task performance

A few studies have examined selective attention in Stroop task performance through ex-Gaussian analyses of response time (RT) distributions. It has remained unclear whether the tail of the RT distribution in vocal responding reflects spatial integration of relevant and irrelevant attributes, as suggested by Spieler, Balota, and Faust (2000 Spieler, D. H., Balota, D. A. and Faust, M. E. 2000. Levels of selective attention revealed through analyses of reaction time distributions. Journal of Experimental Psychology: Human Perception and Performance, 26: 506–526. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). Here, two colour–word Stroop experiments with vocal responding are reported in which the spatial relation between colour and word was manipulated. Participants named colours (e.g., green; say “green”) while trying to ignore distractors that were incongruent or congruent words (e.g., red or green), or neutral series of Xs. The vocal RT was measured. Colour words in colour, white words superimposed onto colour rectangles (Experiment 1), and colour rectangles combined with auditory words (Experiment 2) yielded Stroop effects in both the leading edge and the tail of the RT distributions. These results indicate that spatial integration is not necessary for effects in the tail to occur in vocal responding. It is argued that the findings are compatible with an association of the tail effects with task conflict.     

Exploring relations between task conflict and informational conflict in the Stroop task

In this study, we tested the proposal that the Stroop task involves two conflicts—task conflict and informational conflict. Task conflict was defined as the latency difference between color words and non-letter neutrals, and manipulated by varying the proportion of color words versus non-letter neutrals. Informational conflict was defined as the latency difference between incongruent and congruent trials and manipulated by varying the congruent-to-incongruent trial ratio. We replicated previous findings showing that increasing the ratio of incongruent-to-congruent trials reduces the latency difference between the incongruent and congruent condition (i.e., informational conflict), as does increasing the proportion of color words (i.e., task conflict). A significant under-additive interaction between the two proportion manipulations (congruent vs. incongruent and color words vs. neutrals) indicated that the effects of task conflict and informational conflict were not additive. By assessing task conflict as the contrast between color words and neutrals, we found that task conflict existed in all of our experimental conditions. Under specific conditions, when task conflict dominated behavior by explaining most of the variability between congruency conditions, we also found negative facilitation, thus demonstrating that this effect is a special case of task conflict.     

Attitude of judgment and reaction time in estimation of size at a distance

Experiment I obtained scalar (absolute) size estimates under full cue conditions for rectangular standards that were presented at distances ranging from 1.22 to 3.05 m. Size-estimate reaction times increased linearly with increasing viewing distance. Reaction times for distance estimation were the same at all distances. Experiment II obtained size estimates over distances ranging from 1.22 to 5.49 m under objective and phenomenal size-estimation instructions. Only objective size-estimate reaction times increased with distance. Phenomenal size estimates were faster then objective estimates and were the same for all viewing distances. It was concluded that the cognitive operations involved in objective size estimation were responsible for the effects obtained in Experiment I and the similar findings reported in earlier studies by Broota and Epstein (1973).     

Stimulus-dependent modulation of perceptual and motor learning in a serial reaction time task

In two experiments, we investigated the impact of spatial attributes on the representation acquired during a serial reaction time task. Two sequences were used, in which structural regularities occurred either in the horizontal or in the vertical locations of successive stimuli. After training with the dominant hand, participants were required to respond with the non-dominant hand to either the original sequence or to a mirror-ordered version of the original sequence that required finger movements homologous to those used during training. We observed that a difference in reaction times between the two transfer conditions was smaller in the vertical sequence than in the horizontal sequence. This pattern of results was independent of whether three fingers (Experiment 1) were used or only one finger (Experiment 2) was used for responding. This result suggests that perceptual and motor learning mechanisms may be weighted differently depending on the context in which the stimulus is presented.     

Attention, spatial integration, and the tail of response time distributions in Stroop task performance

A few studies have examined selective attention in Stroop task performance through ex-Gaussian analyses of response time (RT) distributions. It has remained unclear whether the tail of the RT distribution in vocal responding reflects spatial integration of relevant and irrelevant attributes, as suggested by Spieler, Balota, and Faust (2000). Here, two colour-word Stroop experiments with vocal responding are reported in which the spatial relation between colour and word was manipulated. Participants named colours (e.g., green; say "green") while trying to ignore distractors that were incongruent or congruent words (e.g., red or green), or neutral series of Xs. The vocal RT was measured. Colour words in colour, white words superimposed onto colour rectangles (Experiment 1), and colour rectangles combined with auditory words (Experiment 2) yielded Stroop effects in both the leading edge and the tail of the RT distributions. These results indicate that spatial integration is not necessary for effects in the tail to occur in vocal responding. It is argued that the findings are compatible with an association of the tail effects with task conflict.