Psychomotor performance as a function of time of day

Previously reported data on mirror tracking were reexamined for time-of-day (TOD) effects on performance and for the interaction of these effects with sex and practice effects. Analyses showed a significant linear decline of mean score from 0900 through 1300 hours, a sharp postlunch recovery at 1400 hours, and another significant linear decline from 1400 through 1700 hours. These effects were orthogonal to sex and practice effects. Discussion emphasized the importance of control for time of day in experimental design and suggested several hypotheses about the decremental effects of time of day.     

Reaction time as a function of stimulus uncertainty on a single trial

In a discrete choice-reaction-time experiment, reaction times were measured between the onset of a light and the start of S’s pencil toward that light. The reaction time of unpracticed Ss, not aware that their first “practice” trial was being measured, increased as a linear function of stimulus uncertainty. Since this occurred without any prior experience, the effect must have been due to S’s set or expectancy regarding the nature of the future task, formed while the instructions for the task were being given.     

Reaction time as a function of stimulus intensity for the monkey

Monkeys were trained to release a telegraph key in response to a visual or auditory stimulus. The latency of the key release response was measured for different stimulus intensities. In general, the relation between latency and intensity is inverse and exponential with greater variability of latency at the lower intensities. Some preliminary data involving differential reinforcement of short latencies are presented.     

Identification reaction time as a function of target and field object orientation

Four experiments were conducted investigating the effects of (a) target versus field object orientation, (b) target upside up versus target upside down and (c) inverting versus noninverting lenses on object identification reaction time. Inverting versus noninverting lenses had no significant effect. Target versus field orientation was significant when objects commonly found on a desk were used. Target upside up versus upside down was not significant. With letters as target and field objects, orientation was not significant. When the target letters were simply inverted (rotated 180 degrees on the horizontal axis), however, forming nonfamiliar patterns, the target upside up versus upside down was significant, with the upside down condition resulting in a longer mean reaction time. The complexity and similarity of target and field objects is offered as an explanation of the results.     

A field test of the quiet hour as a time management technique

IntroductionThis field study tested the effectiveness of quiet hours (an hour free of any phone calls, visitors or incoming emails).ObjectiveBased on interruptions research and on a behavioral decision-making approach to time management, we argue that establishing quiet hours is a precommitment strategy against predominantly harmful interruptions. Furthermore, conscientiousness and the use of other time management techniques should moderate the effects of the quiet hour.MethodWe tested this by using a two-week experimental diary study with managers as participants.ResultsMulti-level analyses showed that a quiet hour improved the performance on a task worked on during the quiet hour in comparison to a similar task on a day without a quiet hour. Furthermore, overall performance was higher on days with a quiet hour than on days without one. Conscientiousness acted as a moderator, unlike the use of other time management techniques.ConclusionThese results imply that more people should consider implementing a quiet hour, especially if they are non-conscientious.     

Reaction time to the onset and offset of electrocutaneous stimuli as a function of rise and decay time

Reaction times were obtained to the onset and offset of 70-cps electrocutaneous signals of five rise and decay times and five intensity levels. The results show that both onset and offset RTs increase linearly with increased rise and decay times. With fast rates of rise or decay, the onset produces faster RTs than the cessation of stimulation. The opposite effect is found when long rise and decay times are used. Interpretations of these results are given in terms of neural adaptation and accommodation.     

Reaction time to the onset and offset of electrocutaneous stimuli as a function of rise and decay time

Reaction times were obtained to the onset and offset of 70-cps electrocutaneous signals of five rise and decay times and five intensity levels. The results show that both onset and offset RTs increase linearly with increased rise and decay times. With fast rates of rise or decay, the onset produces faster RTs than the cessation of stimulation. The opposite effect is found when long rise and decay times are used. Interpretations of these results are given in terms of neural adaptation and accommodation.     

Reaction time as a function of the intensity and probability of occurrence of vibrotactile signals

Three Ss made judgments of the presence or absence of a burst of 60-cps vibration onthe index fingertip.The probability of S’s reporting the presence of a signal was found to be influenced by signal probability and signal intensity. Mean reaction time for reporting the presence of a signal decreased as a function of signal intensity and signal probability whereas mean reaction time for reporting the absence of a signal increased as a function of signal intensity and signal probability. On trials where no signal was presented mean R T for reporting a signal decreased with increases in the signal probability whereas mean RT for reporting the absence of a signal increased with increases in signal probability. The results were interpreted as support for the hypothesis that S’s decision time was longer the closer on the sensory continuum a particular observation was to his criterion.     

Reaction time to a second stimulus as a function of intensity of the first stimulus

Reaction time (RT) to the second of two stimuli presented in rapid succession was examined as a function of the intensity of the first stimulus (S₁). It was found that the delay in RT₂ was greater following a dim first stimulus than following a bright first stimulus. The magnitude of this increase corresponded to the difference in RTs to the two intensity levels of S₁. These results support the prediction of a single channel model of response selection. Examination of mean first RTs revealed a general elevation in latency of RT. However, since this increase was not influenced by the inter-stimulus interval (ISI) or by the intensity of the second stimulus (S₂), and since the same increase was found on “catch trials“ where no S₂ was presented, this increase is considered to be a function of change in set in the double response situation.     

Visual field dependence as a navigational strategy

Visual perception is an important component of environmental navigation. Previous research has revealed large individual differences in navigational strategies (i.e., the body’s kinesthetic and embodied approach to movement) and the perception of environmental surfaces (via distance estimations), but little research has investigated the potential relationship between these sources of individual variation. An important navigational strategy is the interaction between reliance on visual cues and vestibular or proprioceptive cues. We investigated the role of this navigational strategy in the perception of environmental surfaces. The results supported three embodied evolutionary predictions: Individuals who were most reliant on visual context (1) overestimated vertical surfaces significantly more, and (2) feared falling significantly more, than did those who were least reliant on visual context; and (3) all individuals had roughly accurate horizontal distance estimates, regardless of their navigational strategy. These are among the first data to suggest that individual differences in perception are closely related to the individual differences in navigation that derive from navigational risks. Variable navigational strategies may reflect variable capacities to perceive and navigate the environment.     

Reaction time normative data for the IAPS as a function of display time, gender, and picture content

This study aimed to extend the International Affective Picture System (IAPS; Lang, Bradley, & Cuthbert, 2005) norms by obtaining reaction time (RT) normative data for 308 selected photographs. Pictures were presented one at a time for 33, 100, or 250 msec, or under free-time display, to 96 women and 48 men. The participants’ task involved assessing the emotional valence of each picture and responding as quickly as possible as to whether it was unpleasant, neutral, or pleasant. RTs provided an index of processing efficiency. The manipulation of display time served to estimate the time course in the valence identification of each picture. Some categories of depicted scenes (e.g., erotica and mutilations) were classified more consistently and efficiently than were others as pleasant or unpleasant. There were minimal differences between men and women. Overall, the present data provide researchers investigating cognition/emotion relationships with an objective criterion to select pictorial stimuli on the basis of RTs. Data for all pictures may be downloaded from brm.psychonomic-journals.org/content/supplemental.