Deeper processing at target selection increases the magnitude of negative priming.

Do deeper levels of processing produce equivalent priming effects at all stages of task performance? In Experiment 1, we varied the level of processing factorially across two task stages--target selection and response selection. Each stage required perceptual (e.g., color) or conceptual (e.g., friendliness) processing of stimulus items (i.e., animal names). Negative priming was substantially greater when deeper processing was required at the target selection stage, but it was unaffected by the level of processing at the response selection stage. In contrast, positive priming was greater when deeper processing was required at the response selection stage, but it was unaffected by processing at the target selection stage. In Experiment 2, we generalized this finding using a task in which numeric targets were selected on the basis of their parity. As in Experiment 1, the deeper level of processing at the target selection stage produced a larger negative priming effect. These results illuminate the role of target selection demands in modulating the strength of negative priming.

Cognitive effects of life stress and learned helplessness.

Abstract Stressful life events and learned helplessness attributional styles have been shown to impact a variety of personal outcomes. This study examined how these factors influence two classes of cognitive behaviors: the occurrence of intrusive thoughts and performance in memory and verbal-spatial reasoning tasks. Negative life change and attributions for negative events predicted different types of cognitive responses. Individuals reporting higher levels of life stress were more likely to experience distracting thoughts that were unrelated to the current task, whereas individuals with learned helplessness attributional styles tended to have more worrisome thoughts about their task performance. In general, individuals reporting high levels of negative life stress tended to perform more poorly in tasks, whereas individuals with learned helplessness attributional styles tended to perform better than those who did not share this explanatory style. These results suggest that life stress and attributional style have important influecnes on cognitive processes, and that a learned helplessness attributional style can have beneficial effects on behavior in some situations.

Vibrotactile forward masking: effects of the amplitude and duration of the masking stimulus.

Tactile thresholds for detecting a 50-ms signal presented 25 ms after the termination of a masking stimulus increased as a function of the amplitude level and duration of the masking stimulus. The effects were similar in both the P and NP I channels measured at 250 and 20 Hz, respectively. It was concluded that the increased masking caused by increasing the duration of the masking stimulus resulted from processes other than or in addition to temporal integration--the latter being a characteristic of the P, but not the NP I, channel. The slopes of the masking functions, in which threshold shifts were plotted as a function of masking-stimulus sensation level, were consistently greater for 20-Hz than for the 250-Hz stimuli, suggesting that masking efficiency is greater in the NP I than in the P channel.