A meta-analytical review of the impact of mindfulness on creativity: Framing current lines of research and defining moderator variables.

Findings relating to the impact of mindfulness interventions on creative performance remain inconsistent, perhaps because of discrepancies between study designs, including variability in the length of mindfulness interventions, the absence of control groups or the tendencies to explore creativity as one unitary construct. To derive a clearer understanding of the impact that mindfulness interventions may exert on creative performance, two meta-analytical reviews were conducted, drawing respectively on studies using a control group design (n = 20) and studies using a pretest-posttest design (n = 17). A positive effect was identified between mindfulness and creativity, both for control group designs (d = 0.42, 95% CIs [0.29, 0.54]) and pretest-posttest designs (d = 0.59, 95% CIs [0.38, 0.81]). Subgroup analysis revealed that intervention length, creativity task (i.e., divergent vs. convergent thinking tasks) and control group type, were significant moderators for control group studies, whereas only intervention length was a significant moderator for pretest-posttest studies. Overall, the findings support the use of mindfulness as a tool to enhance creative performance, with more advantageous outcomes for convergent as opposed to divergent thinking tasks. We discuss the implications of study design and intervention length as key factors of relevance to future research aimed at advancing theoretical accounts of the relationship between mindfulness and creativity.

Prospective memory deficits in illicit polydrug users are associated with the average long-term typical dose of ecstasy typically consumed in a single session.

RATIONALE: Neuroimaging evidence suggests that ecstasy-related reductions in SERT densities relate more closely to the number of tablets typically consumed per session rather than estimated total lifetime use. To better understand the basis of drug related deficits in prospective memory (p.m.) we explored the association between p.m. and average long-term typical dose and long-term frequency of use. METHOD: Study 1: Sixty-five ecstasy/polydrug users and 85 nonecstasy users completed an event-based, a short-term and a long-term time-based p.m. task. Study 2: Study 1 data were merged with outcomes on the same p.m. measures from a previous study creating a combined sample of 103 ecstasy/polydrug users, 38 cannabis-only users, and 65 nonusers of illicit drugs. RESULTS: Study 1: Ecstasy/polydrug users had significant impairments on all p.m. outcomes compared with nonecstasy users. Study 2: Ecstasy/polydrug users were impaired in event-based p.m. compared with both other groups and in long-term time-based p.m. compared with nonillicit drug users. Both drug using groups did worse on the short-term time-based p.m. task compared with nonusers. Higher long-term average typical dose of ecstasy was associated with poorer performance on the event and short-term time-based p.m. tasks and accounted for unique variance in the two p.m. measures over and above the variance associated with cannabis and cocaine use. CONCLUSIONS: The typical ecstasy dose consumed in a single session is an important predictor of p.m. impairments with higher doses reflecting increasing tolerance giving rise to greater p.m. impairment.

Spatial orienting of attention in dyslexic adults using directional and alphabetic cues.

Spatial attention performance was investigated in adults with dyslexia. Groups with and without dyslexia completed literacy/phonological tasks as well as two spatial cueing tasks, in which attention was oriented in response to a centrally presented pictorial (arrow) or alphabetic (letter) cue. Cued response times and orienting effects were largely similar in dyslexic and nonimpaired readers. The one distinct pattern that emerged showed dyslexic adults to have smaller orienting effects in the right than left visual field for letter cues, whereas typical readers showed the opposite pattern. These smaller orienting effects appeared to characterize the dyslexic group as a whole and not only one or two individuals. Our results suggest that dyslexic adults may have a subtle impairment in orienting visual attention when processing alphabetic (but not pictorial) cues. Several interpretations of these findings are considered, including links with a phonological deficit and/or a difficulty in shifting attention in the direction of reading.

Gender differences on the semantic flanker task using transposed-letter target words.

Previous research has demonstrated that men and women are differentially influenced by irrelevant distractors. Other lines of evidence have suggested that increasing the perceptual load of a task reduces distractor interference for participants generally. The present study examined these effects using a semantic version of the flanker task; participants made speeded responses to category target words that were flanked by irrelevant distractors. The response mapping between the target and flanker words was either congruent (mapped to the same motor response) or incongruent (target word mapped to a different motor response to that of the flankers). Target words were presented either normally (e.g., table: low perceptual load) or with the beginning letters transposed (e.g., atble: high perceptual load). The results revealed that women showed a larger congruency effect than men but this was not due to greater interference on incongruent trials. While men and women made faster responses to normal than to transposed target words, this was similar in magnitude. The magnitude of the flanker effect for normal and transposed target words was significantly correlated in men but not in women. These findings are consistent with the view that women may process target words to a deeper level than men and therefore may engage in more conflict monitoring then men.

Effects of ecstasy/polydrug use on memory for associative information.

RATIONALE: Associative learning underpins behaviours that are fundamental to the everyday functioning of the individual. Evidence pointing to learning deficits in recreational drug users merits further examination. OBJECTIVES: A word pair learning task was administered to examine associative learning processes in ecstasy/polydrug users. METHODS: After assignment to either single or divided attention conditions, 44 ecstasy/polydrug users and 48 non-users were presented with 80 word pairs at encoding. Following this, four types of stimuli were presented at the recognition phase: the words as originally paired (old pairs), previously presented words in different pairings (conjunction pairs), old words paired with new words, and pairs of new words (not presented previously). The task was to identify which of the stimuli were intact old pairs. RESULTS: Ecstasy/ploydrug users produced significantly more false-positive responses overall compared to non-users. Increased long-term frequency of ecstasy use was positively associated with the propensity to produce false-positive responses. It was also associated with a more liberal signal detection theory decision criterion value. Measures of long term and recent cannabis use were also associated with these same word pair learning outcome measures. Conjunction word pairs, irrespective of drug use, generated the highest level of false-positive responses and significantly more false-positive responses were made in the divided attention condition compared to the single attention condition. CONCLUSIONS: Overall, the results suggest that long-term ecstasy exposure may induce a deficit in associative learning and this may be in part a consequence of users adopting a more liberal decision criterion value.

Visual attention in adults with developmental dyslexia: evidence from manual reaction time and saccade latency.

Two studies were conducted to investigate visual attention deficits in dyslexia. In Experiment 1, adults with dyslexia and age- and IQ-matched controls completed a simple cueing task; participants responded to briefly presented (20 ms) eccentric targets (3 degrees , 6 degrees , or 9 degrees ) with a key press. In Experiment 2, the same participants completed a saccade version of the task, and saccade amplitude, accuracy, and latency were measured. The results revealed comparable performance between the groups on the manual reaction time task. The groups also performed similarly in saccade accuracy and latency. Moreover, neither group showed a visual field asymmetry in their performance, with the exception that adults with dyslexia showed longer saccade latency for 9 degrees targets presented to their left visual field than did controls. However, on the latter measure, the majority (78%) of those with dyslexia performed within the range of the control group. Correlational analyses revealed associations between reading and phoneme awareness in both groups, but phoneme awareness was not associated with visual attention in adult dyslexics. Together, the results are not compatible with a visual attention deficit in adult dyslexia, while they provide support for the phonological deficit hypothesis.

Smooth pursuit eye movements and phonological processing in adults with dyslexia.

The extent to which adults with dyslexia are characterized by concurrent smooth pursuit eye movement and phonological difficulties was investigated, as was the relationship between performance on these respective tasks and literacy skills. A total of 19 adults with dyslexia and 19 age- and IQ-matched controls undertook a comprehensive battery of psychometric, literacy, and phonological tests. Smooth pursuit initiation was measured quantitatively under both gap and nongap conditions. The results revealed that adults with dyslexia had longer smooth pursuit latencies; however, both groups showed a similar gap effect. Moreover, the group with dyslexia had poorer phonological skills than controls. The smooth pursuit impairments affected 37% of the group whereas the phonological difficulties-most notably phoneme deletion latency-were severe among participants with dyslexia, affecting 89% of the group. Phonological processing tasks, but not the smooth pursuit task, were strongly correlated with nonword- and word-decoding skills in the group with dyslexia. These results suggest a lower incidence of smooth pursuit problems than phonological difficulties in dyslexia, and that the latter tasks are more critical for word level decoding.

Fine motor skill performance in left- and right-handers: Evidence of an advantage for left-handers.

A total of 22 right-handed and 22 left-handed participants performed tasks on a well-established test of manual dexterity in addition to completing the Waterloo Handedness Questionnaire. Analysis of Variance revealed that left-handers performed significantly better on the Purdue pegboard test when the task relied on the co-ordination of both the left and right hands. Multiple regression analysis indicated that the Purdue pegboard assembly task is a predictor of self-reported hand preference and of handedness when classified by the Waterloo Handedness Questionnaire. Left-handers showed a smaller performance difference between hands, suggesting an advantage in using their non-preferred hand, although this did not lead to a better performance on a bimanual placement task. These results suggest that left-handers perform more proficiently when hand actions have to be alternated in completing a task. The superior performance of the non-preferred hand in left-handers might be explored to develop future behavioural predictors of handedness.