Reaction time,movement time,and intelligence

Speed of information processing is measured in terms of reaction time (RT) and movement time (MT) to five stimulus displays which differ in the amount of information transmitted, over a range from 0 to 3 bits of information. RT, but not MT, increases as a linear function of the number of bits in the stimulus display. RT and MT show reliable individual differences which are significantly correlated with intelligence as measured by Raven's Standard Progressive Matrices.     

Choosing between fixed time and variable time shock

Two experiments are reported dealing with choice of fixed or variable time shock schedules with and without signals. Response independent shock was presented on either a fixed-time or a variable-time schedule and subjects could change from one condition to the other for short periods after which the initial condition was automatically reinstated. In the first experiment shocks for both schedules were either unsignalled (6 subjects) or signalled (3 subjects) and all subjects changed from a schedule of variable-time shock to a fixed-time one. Subjects that were given the opportunity to change in the reverse direction did not do so. Opposite findings were obtained in the second experiment (7 subjects) comparing unsignalled fixed-time shock with signalled variable-time shock. Six of the seven subjects changed from the fixed-time schedule to the signalled variable-time one but not the reverse. The data were considered consistent with an analysis of choice based on the reinforcing value of discriminable shock-free periods.     

Responding time: A response equivalent to inspection time

A response equivalent to ‘inspection time’ (IT) was developed using a reaction time task in which Ss were required to respond as quickly and accurately as possible to whichever one of two lights appeared on each of a number of trials. The appearance of the lights was followed on all trials by a backward mask. IT was estimated for each S as the shortest duration between the onsets of the light and the backward mask at which the S could respond accurately on virtually every trial. An estimate of ‘responding time’ was then made by setting the duration between the stimulus onset and the mask to each S's individual IT and gradually reducing the time between trials so that Ss had less and less time in which to respond correctly. Responding time was taken to be the shortest such interval at which the S could respond accurately on virtually every trial. This measure was found to be reliable although quantitatively different estimates were obtained using two different methods of presenting the stimulus trials. Responding time was longer for a group of lower-intelligence Ss than for a group of higher-intelligence Ss and the measure was also found to correlate with measured intelligence in the former group. However, it did not itself correlate significantly with IT suggesting that responding time and IT may be measuring different underlying processes.     

Target-size influences on reaction time with movement time controlled

The variable that affect motor programming time may be studied by changing the nature of the response and measuring the subsequent changes in reaction time (RT). One notion of motor programming suggests that aiming responses with reduced target size and/or increased target amplitude require more "complex" motor programs that require longer RTs. In a series of five experiments which movement time (MT) was experimentally varied target size neither influences RT when the movement amplitude was 2 or 30 cm nor when the target sizes differed by as much as a factor of 16:1. Increasing the movement amplitude from 15 to 30 cm also had no influence on RT. Movement time, however, did affect RT, with 200-msec movements having longer RTs than 120-msec movements. Target size and movement amplitude did not appear to be factors that influence programming time or program complexity.     

Memory of elapsed time and feeling of time discrepancy

In dating past events, one sometimes recalls inaccurate dates and tends to estimate recent events too remotely and remote events too recently (telescoping). On the other hand, even when one knows the exact dates of events, subjective time could be elastic and often different from objective time. This Feeling of Time Discrepancy between objective and subjective elapsed times was examined with two autobiographical events. Results showed that (1) subjects reported a discrepancy even if the exact dates of events were known and (2) the discrepancy for entrance into university was higher than that for graduation from high school, even when they happened at almost same time. The results are discussed in terms of "location" and "distance" theories, Kemp's 1999 associative model of dating, and Conway's 2000 self-memory system. Autobiographical memory may be organized in terms of present self-concept with our past fitted to the present self-concept. However, if autobiographical memory changes greatly, we cannot share autobiographical memory with other people. We may be adapted to the present life by making only a sense of the subjective elapsed time of each event change with the accurate time information of the autobiographical facts held.     

Pause time and phonation time in stuttering and cluttering

This study examined the potential usefulness of automated analysis of on-off speech patterns in the differentiation of stuttering from cluttering. Two groups of fifteen persons who had been previously classified as stutterers and clutterers served as subjects for this investigation. The data indicate that stutterers tend to have greater mean pause times and lower mean phonation times than clutterers. This result corresponds to the clinically observable characteristics of these groups. It is concluded that automated analysis of on-off speech patterns provides some basis for the differential diagnosis of stuttering from cluttering.Supported, in part, by a general research support grant from NIMH to the Research Foundation for Mental Hygiene, Inc.     

Failing time after time: time perspective,procrastination, and cognitive reappraisal in goal failure

This research novelly explores how Future Time Perspective (FTP) plays a role in reflecting on goal failure and striving for future goals. Participants (N = 139) completed questionnaires assessing recent goal failure, procrastination, emotion regulation and FTP, then coded as either High or Low in FTP. Results support hypotheses that despite goal failure, those high in FTP procrastinated less, planned more and used more cognitive reappraisal strategies. Further, procrastination and cognitive reappraisal significantly predicted FTP scores. Thus, goal failure may be an essential part of learning how to achieve high self‐regulation goals. However, it may discourage some from trying again, particularly those low in FTP. Findings suggest the FTP may offer a strategy to aid attainment of important high self‐regulated, long‐term goals.     

Bratman on identity over time and identification at a time

According to reductionists about agency, an agent’s bringing something about is reducible to states and events (such as desires and beliefs) involving the agent bringing something about. Many have worried that reductionism cannot accommodate robust forms of agency, such as self-determination. One common reductionist answer to this worry (which I call “identification reductionism”) contends that self-determining agents are identified with certain states and events, and so these states and events causing a decision counts as the agent’s self-determining the decision. In this paper, I discuss Michael Bratman’s well-known identification reductionist theory and his general strategy of grounding an agent’s identification at a time in the agent’s identity over time. I develop two constraints that an adequate identification reductionist theory must satisfy, argue that Bratman’s theory cannot satisfy both, and show that his general strategy for grounding an agent’s identification at a time in the agent’s identity over time is without merit.     

On measuring the minimum detection time: A simple reaction time study in the time estimation paradigm

Kornblum's time estimation paradigm, together with the so‐called ‘race model’, provides an appealing alternative for measuring the ‘cut‐off’ which separates ‘true’ reaction times from anticipatory reaction times. However, the model is not precise enough to reveal the relation between the signal intensity and the ‘cut‐off’. Accordingly, Kornblum's model is extended with an emphasis on the measure of the ‘cut‐off’. Another aspect of the extension is to use a parametric method to analyse the data. In particular, it is assumed that the time estimation‐induced latency is gamma distributed and the signal‐induced latency is Weibull distributed, with the latter shifted by the ‘cut‐off’. The rationale behind the parametric assumption is discussed. For illustrative purposes, two pieces of experimental work are presented. Since the core of the race model is the assumption of an independent race between the time estimation process and the detection process, the first experiment tests whether, for the same signal intensity, the signal‐induced latency distribution is invariant across different time intervals; the second experiment tests whether, for the same time interval, the time estimation‐induced latency distribution is invariant across different signal intensity conditions. The data from the second experiment are also used to test various parametric assumptions in the model, which include the signal effect on the ‘cut‐off’. The new model fits the data well.     

Effects of electromyographic biofeedback on reaction time and movement time

The effects of electromyographic (EMG) biofeedback on reaction time (RT) and movement time (MT) were investigated utilizing 42 right-handed, male subjects from a university population. Subjects were randomly divided into three groups, a control group and two experimental groups. Both experimental groups were exposed to their EMG signals from their triceps brachii during the task, one experimental group received written information explaining the purpose of the EMG was to improve performance through biofeedback. Reaction times of the first block of 25 trials were significantly faster than those on the subsequent three blocks of trials for all groups. This provided evidence of learning. No other significant effects for reaction times were observed. Mean movement time for the EMG-only group was significantly slower than the means of either the Control group or EMG-Biofeedback group, with no difference between the latter two. The differences between experimental groups may have been related to alteration of strategy, anxiety, motivation.     

Reaction time and movement time after active and passive smoking

Reaction time and movement time were studied following active and passive smoking in two groups of 20 women. All subjects were tested under a clean air and smoky air condition and the results showed that, while there was no difference between groups for either measure in the clear air condition, the active smokers had faster reaction time and movement time in the smoky air condition. Smoky air had no significant effect on the responses of the passive smoking group.     

Development of time sensitivity: Duration ratios in time bisection

This study investigated the development of children's abilities to discriminate durations as a function of their ratio and examined whether the ability to discriminate durations that differed by a very difficult ratio is related to the development of attention capacities. Children aged 5 and 8 years, as well as adults, performed a series of temporal bisection tasks with a ratio between the short and the long anchor duration that was changed to control the difficulty of the task (5:6, 2:3, and 1:2) in two duration ranges (<1 s and >3 s). In addition, they completed neuropsychological tests in order to assess their short-term memory, working memory, and visual attention abilities. The results showed that, at ratios of 2:3 and 1:2, most participants were able to discriminate the anchor durations in bisection. However, their sensitivity to time improved, whatever the duration range, both as the distance between the anchor durations increased and with increasing age. For the smallest duration ratio (5:6), few of the children were able to discriminate the anchor durations in the bisection task in comparison to adults. Hierarchical regression analyses performed on the neuropsychological tests revealed that, for the 2:3 ratio between anchor durations, the participants' visual attention scores explained a large part of the variance in time sensitivity. The children's lower temporal sensitivity was probably due to their limited visual attention abilities, thus explaining the difficulty they experienced in discriminating very close durations (5:6).     

Interreinforcement time, work time, and the postreinforcement pause

Six rats were trained with food deliveries contingent upon their pressing a lever and holding it down for fixed, cumulative durations. Hold requirements were varied from 7.5 seconds to 120 seconds. Lever holding was maintained reliably at hold requirements as long as 30 seconds to 105 seconds for different rats. At longer hold requirements, lever holding was erratic and tended to occur only early in sessions. At shorter and intermediate requirements, the patterns of lever holding resembled those of responding under fixed-ratio schedules for discrete responses, with breaks in responding immediately after reinforcement alternating with relatively continuous lever holding until the next reinforcement. At longer hold requirements, postpause lever holding frequently was interrupted with additional pauses. The duration of postreinforcement pauses increased linearly with the scheduled hold requirement. However, for five of six rats, the hold requirement, which represents the actual time spent lever holding per reinforcer, accounted for somewhat less variance in pause duration than did interreinforcement time.     

Stress in time

The goals of this research were to determine whether speakers adjust the stress patterns of words within sentences to create an alternation between strong and weak beats and to explore whether this rhythmic alternation contributes to the characteristics stress differences between two major lexical categories of English. Two experiments suggested that speakers do alter lexical stress in accordance with rhythmic biases. When speakers produced disyllabic pseudowords in sentence contexts, they were more likely to place stress on the first syllable when the pseudoword was preceded by a weak stress and followed by a strong one than when the strong stress preceded and the weak followed. This occurred both when the pseudowords served as nouns and when they served as verbs. Text analyses further revealed that weakly stressed elements precede nouns more often than verbs, whereas such elements follow verbs more often than nouns. Thus, disyllabic nouns are more likely than disyllabic verbs to occupy contexts biased toward trochaic rhythm, a finding consistent with leftward dominant stress in disyllabic English nouns. The history of stress changes in English nouns and verbs also conforms with the view that rhythmic context may have contributed to the evolution of stress differences. Together, the findings suggest that the citation stress patterns of words may to some degree reflect adaptations of lexical knowledge to conditions of language performance.