Recent studies suggest that timing and tasks involving executive control processes might require the same attentional resources. This should lead to interference when timing and executive tasks are executed concurrently. This study examines the interference between timing and task switching, an executive function. In four experiments, memory search and digit classification were performed successively in four conditions: search-search (search followed by search), search-digit, digit-search and digit-digit. In a control reaction-time condition, participants provided RT responses in each of the two tasks. In a time-production condition, an RT response was provided to the first stimulus, but the response to the second stimulus, S2, was given only when participants judged that a previously presented target duration had elapsed.When responding to S2 required a switch, RTs to S2 were longer but produced intervals were unaffected. These results show that memory search affects concurrent timing, but not task switching. Task switching seems therefore to be one executive function not interfering with timing.

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For five individuals, a social network was constructed from a series of his or her dreams. Three important network measures were calculated for each network: transitivity, assortativity, and giant component proportion. These were monotonically related; over the five networks as transitivity increased, assortativity increased and giant component proportion decreased. The relations indicate that characters appear in dreams systematically. Systematicity likely arises from the dreamer's memory of people and their relations, which is from the dreamer's cognitive social network. But the dream social network is not a copy of the cognitive social network. Waking life social networks tend to have positive assortativity; that is, people tend to be connected to others with similar connectivity. Instead, in our sample of dream social networks assortativity is more often negative or near 0, as in online social networks. We show that if characters appear via a random walk, negative assortativity can result, particularly if the random walk is biased as suggested by remote associations.

Tones are perceived longer than visual stimuli of same durations. One interpretation of this modality effect is that auditory stimuli capture attention more easily than visual stimuli, resulting in more efficient temporal processing. During a time interval production, expecting a break signal lengthens the produced interval, an effect explained by attention sharing between timing and monitoring for the signal occurrence. In the present study, participants produced a brief time interval defined by a visual or an auditory stimulus and in most trials, there was a break in stimulus presentation. The effect of break expectancy was significantly stronger when the timing stimulus was presented in the visual than in the auditory modality, an interaction supporting attentional interpretations of the modality and expectancy effects. We conclude that auditory stimuli orient attention to time more readily than visual stimuli in a context of attention sharing, which reduces the distracting effect of break expectancy.