Individual Differences In Reaction Time Research Articles

Relationships between simple reaction time and auditory stimulus intensity in people with sensorineural hearing losses

Individual differences in reaction time (RT) to subjectively comfortable, loud, and soft tones were assessed for ten young adult subjects with longstanding, less‐than‐profound sensorineural hearing losses and ten normal hearing controls. To support estimation of the sensory, central, and motor components of RT, subjects were also tested using an equivalent protocol with bright and dim visual stimuli. Subjects with normal hearing listened to 500‐Hz tones at fixed intensities that pilot testing established as corresponding to comfortable, loud, and soft levels. Prior to RT testing, subjects with hearing losses individually adjusted tone intensity to ‘‘most comfortable,’’ ‘‘very loud but not painful,’’ and ‘‘very soft but definitely audible’’ levels. Results show larger modality‐dependent and level‐dependent individual differences in RT than have been previously noted in the literature, pointing up a need for individual subject baselines in cognitive experiments that use RT as a dependent variable. Results also indicate that the typically small range between threshold and pain in listeners with hearing losses is, with respect to RT, functionally equivalent to larger ranges in normal hearing listeners in some individuals but not in others. [Work supported by NIH‐NIDCD.]

Verbal ability and speed of information-processing

Reaction times obtained by five elementary tasks were investigated for the presence of individual differences related to verbal ability. Two tasks required subjects to retrieve information from either long-term or short-term memory, whereas the other tasks required subjects to receive external information. Significant correlations between a verbal-comprehension scale and reaction times of the tasks requiring to retrieve information from memory were observed. These correlations were only slightly reduced by eliminating the contribution of general ability. In contrast, a word-fluency scale did not correlate with any reaction time. Furthermore, substantial correlations were found between general ability and four of the five reaction times. It is concluded that individual differences in reaction time can be related to a specific ability over the influence of general ability when the respective task poses an appropriate demand to information processing.

The contribution of access to external information, stimulus complexity, and variability to cognitive abilities

Reaction times were obtained by means of four tasks requiring simple information processing skills and subsequently correlated with scales representing various cognitive abilities. The tasks differed according to the type of access to external information and to the degree of stimulus complexity. Substantial correlations between all the reaction times and two scales representing general intelligence were found. Further significant correlations resulting from specific information processing skills were observed. The reaction time obtained by an easy access to information correlated with perceptual speed and space, whereas a hard access to information led to a correlation with closure and space in one of two cases. The reaction time for stimulus complexity was correlated with verbal intelligence. Significant correlations between cognitive abilities and variability were also found. However, a high correlation between variability and the corresponding reaction time suggests that individual differences in reaction time are partly due to variability.

Simple reaction time as a suppressor variable in the chronometric study of intelligence

Individual differences in reaction time (RT) to various elementary cognitive tasks (ECTs) reflect variance in both peripheral (sensorimotor) and central components of information processing. Minimizing the variance associated with peripheral processes by controlling simple RT in chronometric studies of more complex ECTs involving choice, discrimination, memory scanning, or other central processes, can increase the correlation between RTs and scores on complex psychometric tests of ability, thereby identifying more clearly the elementary processes involved in psychometric g and other abilities. Simple RT can be controlled by subtraction, partial correlation, and multiple correlation. The relative effectiveness of the different methods depends on various features of the chronometric data. The methods are explicated, with examples from a study of simple, choice, and discriminative RTs (the odd man out paradigm) in 213 male students from three colleges.

Small cell carcinoma of the lung: An overview

The current study used a magnetoencephalogram to investigate the relationship between high-gamma (52–100 Hz) activity within an attention network and individual differences in behavioral performance among healthy elderly adults. We analyzed brain activity in 41 elderly subjects performing a 3-stimulus visual oddball task. In addition to the average amplitude of event-related fields in the left intraparietal sulcus (IPS), high-gamma power in the left middle frontal gyrus (MFG), the strength of high-gamma imaginary coherence between the right MFG and the left MFG, and those between the right MFG and the left thalamus predicted individual differences in reaction time. In addition, high-gamma power in the left MFG was correlated with task accuracy, whereas high-gamma power in the left thalamus and left IPS was correlated with individual processing speed. The direction of correlations indicated that higher high-gamma power or coherence in an attention network was associated with better task performance and, presumably, higher cognitive function. Thus, high-gamma activity in different regions of this attention network differentially contributed to attentional processing, and such activity could be a fundamental process associated with individual differences in cognitive aging.

Jensen's reaction-time studies: A reply to Longstreth

Longstreth's (1984) critique of Jensen's research on the relationship of IQ to individual differences in visual reaction time (RT), measured in the Hick paradigm, is found to have numerous errors of fact and interpretation, some trivial and some of theoretical importance. Longstreth's narrowly focused and conjectural style of criticism, which peculiarly strains to favor the null hypothesis, unfortunately obscures the essential findings of Jensen's (and others') studies of the RT-IQ relationship. The two main negative verdicts of Longstreth's critique concerning the RT-IQ relationship are refuted by meta-analyses of presently available data. First, not only do individual differences in RT show a significant negative correlation with IQ, but individual differences in the slope of the regression of RT on stimulus set size scaled in bits (i.e., the binary logarithm of the number of potential reaction stimuli) also show a fully significant, albeit low, negative correlation with IQ. Contrary to Longstreth's second negative surmise, meta-analysis also shows that the magnitude of the RT-IQ correlation itself is a linearly increasing (negative) function of stimulus set-size scaled in bits.

EEG correlates of signal rate, time in task and individual differences in reaction time during a five-stage sustained attention task.

Abstract The EEG of 20 subjects was monitored continuously while they performed a sustained attention task in which each subject performed five conditions in different order. All conditions involved regular presentation of digits (stimuli) at the rate of one per two seconds. Subjects were required to respond to particular digits (signals) and signal ratios varied between 10 and 50% over the five conditions. There was a brief rest between each condition, and total task time (including periods of rest) was approximately 112 min. The Results were: (i) Mean reaction time to wanted signals increased following the first condition (independent of signal ratio) and was also longest for the 50% signal ratio condition (independent of order of presentation), (ii) Errors (false positives and misses) increased as a function of signal ratio but not as a function of order of presentation. Subjects with faster mean reaction time committed more errors. However overall absolute error rate was low (3.2% under the most extre...

Concerning individual differences in reaction times.

Concerning individual differences in reaction times.