Divergent and Convergent Group Creativity in an Asynchronous Online Environment

This study examined the influence of various group diversity dimensions on collaborative creativity related to the healthcare system. Research findings on the association between diversity and brainstorming performance has been mixed. Diversity that increases cognitive stimulation or promotes elaboration has been shown to increase group performance. Participants exchanged ideas, replied, and elaborated using an electronic discussion board in an asynchronous fashion in groups of five over a period of 4 weeks. The groups varied in diversity of ethnicity, gender, age, and political orientation, but participants were not made aware of this diversity. Age and gender diversity were related to lower levels of replying to ideas and lower idea novelty but political diversity was related to increased replies and novelty. If a topic engages people with different perspectives to actively respond to others’ ideas, this can increase the creative potential of idea sharing in groups. Political or value-based diversity has the potential for creative solutions if the other participants’ political or value-based identities are not made salient.     

On the relation between feeling of knowing and lexical decision: persistent subthreshold activation or topic familiarity?

Experiment 1 replicated Yaniv and Meyer's (1987) finding that lexical decision and episodic recognition performance was better for words previously yielding high-accessibility levels (a combination of feeling-of-knowing and tip-of-the-tongue ratings) in comparison with those yielding low-accessibility levels in a rare word definition task. Experiment 2 yielded the same pattern even though lexical decisions preceded accessibility estimates by a full week. Experiment 3 dismissed the possibility that the Experiment 2 results may have been due to a long-term influence from the lexical decision task to the rare word judgment task. These results support a model in which Ss (a) retrieve topic familiarity information in making accessibility estimates in the rare word definition task and (b) use this information to modulate lexical decision performance.     

Are rats short-sighted? Effects of stimulus distance and size on visual detection

Behavioural evidence concerning short-sightedness in rats is apparently conflicting: in some experiments rats have performed poorly with visual stimuli further than about 60 cm distant, while in others they have made efficient use of more distant cues, for example to find their way through mazes. However, in the experiments suggesting short-sightedness, the physical size of the stimuli was not varied, so that stimulus distance and visual angle were confounded. In the present experiment, therefore, the size and distance of the stimuli to be detected were varied independently. Over the range tested (30-160 cm), distance was found to produce relatively slight effects on the smallest detectable visual angle, and these tended to diminish with practice. Thus, no good evidence was found for short-sightedness in rats up to 160 cm, a finding consistent with current views of the structure and image-forming capacities of the rat's eye. The smallest detectable targets were, however, surprisingly large in view of the rat's visual acuity (which is about 1c/deg): at the distances tested, animals required considerable training to run reliably to targets subtending less than 5-10° of visual angle. Difficulties in responding to stationary stimuli of this size are likely to restrict severely the use that rats make of vision both in the laboratory and in their natural surroundings.     

Positive Emotions Speed Recovery from the Cardiovascular Sequelae of Negative Emotions

Two studies tested the hypothesis that certain positive emotions speed recovery from the cardiovascular sequelae of negative emotions. In Study 1, 60 subjects (Ss) viewed an initial fear-eliciting film, and were randomly assigned to view a secondary film that elicited: (a) contentment; (b) amusement; (c) neutrality; or (d) sadness. Compared to Ss who viewed the neutral and sad secondary films, those who viewed the positive films exhibited more rapid returns to pre-film levels of cardiovascular activation. In Study 2, 72 Ss viewed a film known to elicit sadness. Fifty Ss spontaneously smiled at least once while viewing this film. Compared to Ss who did not smile, those who smiled exhibited more rapid returns to pre-film levels of cardiovascular activation. We discuss these findings in terms of emotion theory and possible health-promoting functions of positive emotions.     

The influence of only on syntactic processing of "long" relative clause sentences

We report an eye movement experiment investigating the influence of the focus operator only on syntactic processing of "long" relative clause sentences. Paterson, Liversedge, and Underwood (1999) found that readers were garden pathed by "short" reduced relative clause sentences containing the focus operator only . They argued that due to thematic differences between "short" and "long" relative clause sentences, garden path effect might not occur when "long" reduced relative clause sentences are read. Eye-tracking data show that garden path effects found during initial processing of the disambiguating verb of "long" reduced sentences without only were absent or delayed in the case of counterparts with only . We discuss our results in terms of current theories of sentence processing.     

Successive negative contrast in one-way avoidance learning in rats

In three experiments, successive negative contrast was examined in one-way avoidance learning. Reward magnitude in first (pre-shift) and second (post-shift) phases was manipulated by time spent in the safe compartment. Experiment 1 demonstrated that when time in the danger compartment was held constant, a group shifted from a large reward--30 sec spent in the safe compartment--to a small reward--1 sec--showed poor performance and longer response latency than a group conditioned with the small reward in both phases. Experiment 2 replicated this effect with a less intense shock and also demonstrated that a group shifted from large to small reward performed more poorly than a group exposed to large reward--30 sec--in both phases. Finally, Experiment 3 showed that changes in intertrial interval, defined as total time spent in the safe compartment and the danger compartment before the onset of the warning signal, were not responsible for this contrast effect. These results suggest that time spent in a safe place can act as appetitive incentive during one-way avoidance learning.