According to the hypothesis of a scalar property for time, the variability to time ratio should be constant. Three experiments tested the validity of this hypothesis in a restricted range of durations (standard values = 1, 1.3, 1.6, and 1.9 s). In each experiment, time intervals to be discriminated, reproduced, or categorized were presented with…

Vibrotactile intensity-discrimination thresholds for sinusoidal stimuli applied to the thenar eminence of the hand declined as a function of practice. However, improvement was confined to the tactile information-processing channel in which learning had occurred. Specifically, improvements in performance with training within the Pacinian-corpuscle…

In a crowded dynamic world, temporal expectations guide our attention in time. Prior investigations have consistently demonstrated that temporal expectations speed motor behavior. We explore effects of temporal expectation on "perceptual" speed in three nonspeeded, cued recognition paradigms. Different hazard rate functions for the…

Six experiments investigated how changes in stimulus speed influence subjective duration. Participants saw rotating or translating shapes in three conditions: constant speed, accelerating motion, and decelerating motion. The distance moved and average speed were the same in all three conditions. In temporal judgment tasks, the constant-speed…

In four experiments, we investigated whether masked stimuli in priming experiments are subjected to early or to late selection. In Experiment 1, participants classified four target-pictures as being small or large. In line with early selection accounts, prime-pictures with a different perceptual appearance as the experienced targets did not elicit…

Conflict adaptation effects refer to the reduction of interference when the incongruent stimulus occurs immediately after an incongruent trial, compared with when it occurs after a congruent trial. The present study analyzes the key conditions that lead to adaptation effects that are specific to the type of conflict involved versus those that are…

Many studies of cognition and perception use a visual mask to explore the dynamics of information processing of a target. Especially important in these applications is the time between the target and mask stimuli. A plot of some measure of target visibility against stimulus onset asynchrony is called a masking function, which can sometimes be…

Although object-based attention enhances perceptual processing of information appearing within the boundaries of a selected object, little is known about the consequences for information in the object's surround. The authors show that distance from an attended object's center of mass determines reaction time (RT) to targets in the surround. Of 2…

The Ebbinghaus (Titchener) illusion was examined in a remote culture (Himba) with no words for geometric shapes. The illusion was experienced less strongly by Himba compared with English participants, leading to more accurate size contrast judgments in the Himba. The study included two conditions of inducing stimuli. The illusion was weaker when…

The divergent predictions of 2 models of dual-task performance are investigated. The central bottleneck and central capacity sharing models argue that a central stage of information processing is capacity limited, whereas stages before and after are capacity free. The models disagree about the nature of this central capacity limitation. The…