Testing a policy intervention in the lab: differences between students and non-students in switching bank accounts.

The reliance on student samples has long been a subject of debate in experimental approaches to studying behaviour. We contribute to this discussion by looking at differences in financial behaviour between a student and a non-student sample in three sets of lab experiments conducted in Spain, Germany and Poland (n=857). Participants from both samples switched more often and made better financial decisions after they received a message encouraging them to switch financial service providers. While the size of the effect on switching frequency was comparable between the two samples, the effect on switching quality was significantly stronger on non-students. Further analysis suggests this is due to a better performance of students before the prompt leaving less room for improvement by the reminder. Results suggest that experimental evidence derived from students should be generalized with caution.

When Distraction Holds Relevance: A Prospective Memory Benefit for Older Adults.

Evidence is accumulating to show that age-related increases in susceptibility to distracting information can benefit older more than young adults in several cognitive tasks. Here we focus on prospective memory (i.e., remembering to carry out future intentions) and examine the effect of presenting distracting information that is intention-related as a function of age. Young and older adults performed an ongoing 1-back working memory task to a rapid stream of pictures superimposed with to-be-ignored letter strings. Participants were additionally instructed to respond to target pictures (namely, animals) and, for half of the participants, some strings prior to the targets were intention-related words (i.e., animals). Results showed that presenting intention-related distracting information during the ongoing task was particularly advantageous for target detection in older compared to young adults. Moreover, a prospective memory benefit was observed even for older adults who showed no explicit memory for the target distracter words. We speculate that intention-related distracter information enhanced the accessibility of the prospective memory task and suggest that when distracting information holds relevance to intentions it can serve a compensatory role in prospective remembering in older adults.

Too easy? The influence of task demands conveyed tacitly on prospective memory.

Previous research suggests that when intentions are encoded, participants establish an attention allocation policy based on their metacognitive beliefs about how demanding it will be to fulfill the prospective memory (PM) task. We investigated whether tacit PM demands can influence judgments about the cognitive effort required for success, and, as a result, affect ongoing task interference and PM performance. Participants performed a lexical decision task in which a PM task of responding to animal words was embedded. PM demands were tacitly manipulated by presenting participants with either typical or atypical animal exemplars at both instructions and practice (low vs. high tacit demands, respectively). Crucially, objective PM task demands were the same for all participants as PM targets were always atypical animals. Tacit demands affected participants' attention allocation policies such that task interference was greater for the high than low demands condition. Also, PM performance was reduced in the low relative to the high demands condition. Participants in the low demands condition who succeeded to the first target showed a subsequent increase in task interference, suggesting adjustment to the higher than expected demands. This study demonstrates that tacit information regarding the PM task can affect ongoing task processing as well as harm PM performance when actual demands are higher than expected. Furthermore, in line with the proposal that attention allocation is a dynamic and flexible process, we found evidence that PM task experience can trigger changes in ongoing task interference.

Is it relevant? Influence of trial manipulations of prospective memory context on task interference.

Prospective memory (PM) research has often investigated if having an intention interferes with ongoing activities, but rarely by linking the intention to a particular context. We examined effects of trial-by-trial changes in whether the context (defined by colour) was relevant for the nonfocal PM task. The ongoing task involved speeded decisions about the position (left/right) of the upper-case letter in a pair, and the PM task consisted of pressing an additional key if the upper-case and lower-case letters were in a specified colour and the same letter. Trials switched between two colours either randomly or predictably in eight-trial blocks. We also manipulated the presence/absence of occasional same-letter pairs in the irrelevant context. Results showed higher cost of having a nonfocal PM task when ongoing stimuli matched than when they mismatched the target's colour. Moreover, cost for intention-irrelevant stimuli was minimized, though never eliminated, by blocking match/mismatch trials. These findings highlight the role that local changes in intention-related context play in task interference and support a view of monitoring as a flexible mechanism. Additionally, the study introduced a novel way of embedding intention-related events in the irrelevant context shortly before the occurrence of PM targets, with results tentatively suggesting that such events might impair target detection.

Target context specification can reduce costs in nonfocal prospective memory.

Performing a nonfocal prospective memory (PM) task results in a cost to ongoing task processing, but the precise nature of the monitoring processes involved remains unclear. We investigated whether target context specification (i.e., explicitly associating the PM target with a subset of ongoing stimuli) can trigger trial-by-trial changes in task interference according to stimulus relevance for the nonfocal PM task. Participants performed a lexical decision task in which a PM task (press F6 when a target syllable appeared) was embedded. The target syllable always occurred in word trials, but we manipulated participants' expectations regarding the target context by instructing them that targets would occur in words only (specific condition) or in both words and nonwords (nonspecific condition). A control condition with no PM demands was also included. Although having a PM task led to noticeable slowing on the ongoing task, specifying the PM target context reduced cost to items irrelevant to the intention (nonwords) while leaving PM performance intact. Moreover, higher cost for nonwords in the nonspecific than specific condition was persistent across the ongoing task even though the target syllable was repeatedly presented in words. These results suggest that stimulus processing can be modulated according to participants' expectations about the lexical properties of the target, with trial-by-trial changes in task interference as a function of stimulus relevance to a nonfocal intention observed as a consequence.