EF Science

In contrast, the S-RCD group’s poor performance on the planning component remained significant after controlling for phonological processing. Findings suggest reading comprehension difficulties are linked to executive dysfunction; in particular, poor strategic planning/organizing may lead to reading comprehension problems.

Executive Functions—Working Memory Sentence Span (Swanson, Cochran, & Ewers, 1989; based on Daneman & Carpenter, 1980) On this test, the examiner reads a set of sentences and asks a question about one of them. The child answers and then remembers the last word of each sentence. The number of sentences increases by one sentence with each set. The score for total number of words recalled was used in analyses.Spatial Span (WISC-III–Process Instrument; WISC-III-PI; Kaplan, Fein, Kramer, Delis, & Morris, 1999) This measure uses a spatial span board, upon which 10 blue cubes are mounted in a random order. The researcher taps cubes (one cube per second) in a specified sequence, and the child is asked to replicate the sequence, both forward and backward. Scaled scores from the Backward Span trial were used in analyses.Digit Span (WISC-IV; Wechsler, 2003) Children are asked to repeat aurally presented digit strings, both forward and backward. Scaled scores from the Backward Span trial were used in analyses.

Executive Functions—Planning, Organization, Self-Monitoring Elithorn Mazes (WISC-III-PI; Kaplan et al., 1999) This measure requires the child to examine a visually presented maze and choose a single path that passes through circles within a “lattice” of lines in an inverted triangular structure, without backtracking. The measure provides information about strategic planning and response organization skills. Scaled scores were used in analyses.Trail Making (Delis-Kaplan Executive Function System; D-KEFS; Delis, Kaplan, & Kramer, 2001) The entire D-KEFS Trail Making Test was administered; however, scaled scores from Trial 4: Number/Letter Sequencing, for which the participant was required to switch back and forth between connecting numbers and letters in sequence, were used in analyses.Tower (D-KEFS; Delis et al., 2001) The Total Achievement Score from the Tower Test, a measure of a novel problem solving that requires planning and organization, was also administered. For this task, participants must move disks varying in size across three pegs to build a designated tower using the fewest number of moves possible.

Several hypotheses have been proposed to explain posited PA-related effects on cognitive and academic performance. Regular PA alters neurogenesis and angiogenesis and enhances central nervous system metabolism. 20 Furthermore, it

has been suggested that regular PA increases the availability of certain growth factors, such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF). All these systems and factors are involved with the maintenance and plasticity of the structure and function of the brain, 20 21 and thus with learning and memory

The majority of the studies included in the current review assessed the effects of PA in children aged 6–12 years. Seven studies reported children aged 5 years or younger, 44 51 52 64 77 79 80 and 13 studies included youths (ie, older than 12 years) in their studies. 37 39 43

The shortest intervention duration was 1 week, 54 62 79 and the longest spanned a period of 9 years.

Stratifying the evidence synthesis at the level of outcome for academic performance we conclude that there is strong evidence for beneficial effects of PA on maths performance (beneficial effects on 86% of the outcomes), but inconclusive evidence for language performance (beneficial effect on 27% of the outcomes).

The majority of the intervention studies implemented PA sessions of at least 30 min (n=41).

Many studies applied interventions that were delivered 5 days a week (n=28). The lowest frequency was 1 43 44 and the highest frequency was 6 days per week. 36 65 Most studies (n=34) assessed the effects of PA consisting primarily of aerobic exercise.

Six studies assessed the effects of motor demanding or cognitively engaging activities. 31 43 44 53 54 70 Three of these studies implemented PA games specifically tailored to challenge core executive functions in a gross-motor fashion. 43 44 54 The majority of studies implemented separate PA sessions, whereas 14 studies delivered physically active academic lessons. 42 48 51 62 66 77–80 83 85 87

The intervention also showed small significant beneficial effects on attentional performance and impulse control after 1and 2 years, which were not sustained into the third year. After 9 years, children in the intervention group had significantly higher qualification scores for upper school

Most studies reporting intervention effects on cognitive performance, assessed domains of executive functions (in particular inhibition, working memory , updating, attention, task switching, and planning), speed of information processing, fluid and crystallised intelligence.

In particular, enhanced performance accuracy and increased P3 amplitude were observed in tasks requiring higher amounts of attention, inhibition and cognitive flexibility . T asks requiring less executive control were unaffected by the FITKids intervention.

Subramanian et al 65 reported beneficial effects of structured PA versus unstructured physical and creative sedentary activities in 12- to 17-year-olds on tasks measuring attention, concentration, non-verbal fluency , and mental flexibility

Although we found no evidence for beneficial effects on cognitive performance or overall academic performance, we found strong evidence for beneficial effects of PA on maths performance.

Cognitive/academic performance can theoretically improve through biological or psychosocial pathways, 20 and an interplay between the two is possible and probable.

beneficial effects on maths performance assessed intervention programmes with a minimal frequency of three sessions per week and a minimal programme duration of two school years.

The study conclusions suggested that their findings provided evidence for a more efficient use of neural resources underlying executive functions after participation in PA interventions, reflected in enhanced neural activity in regions supporting attention and working memory functions. 49

PA intervention may result in a more adult-like recruitment of prefrontal brain regions, which is important for many aspects of executive functions.

To establish the effect of combining academic content and PA, there should be at least three groups: (a) the intervention group that combines PA with academic content; (b) the non-active control group that only receives the same academic content as the intervention group, but without PA; (c) the active control group that only receives the PA component.

One high-quality study 54 suggested larger effects of coordinative or perceptual– motor forms of exercise on cognitive performance, particularly on executive functions, than aerobic exercise.

V ariability of practice that is central to coordination and perceptual–motor exercise training, for example, may be an interface between motor and cognitive development promotion. 9

Regarding moderators, it is likely that some children may benefit more from additional PA such as children with low PA levels or overweight children.

Interrupting and limiting sedentary time with standing desks or short activity bouts may be more feasible in the school setting and, therefore, a promising form of intervention.

Based on 11 high-quality intervention studies, we found inconclusive evidence of a beneficial effect of PA interventions on cognitive and overall academic performance in children. However, based on academic outcomes related to mathematics, we found strong evidence for beneficial effects of PA.

However, only one study to date (Wilckens et al., in press) has combined all three variables in a statistical model to test whether sleep can account for the relationship between PA and cognitive performance—the results of this initial study suggest that it can. Similarly, mood is linked both to cognitive performance and PA. While several studies have considered mood along with other behavioral or socioemotional factors in statistical models assessing mechanisms of PA, virtually none have considered the unique or independent contribution of mood to the PA-cognition relationship.

To date, one of the most effective way to trigger neurogenesis appears to be physical exercise (van Praag et al. 1999). Importantly, physical exercise is noninvasive and includes numerous beneficial by-products, such as general health improvement and psychological benefits

However, it is important to note that if newly formed neurons are not integrated within existing neural networks, they typically die within a couple of weeks

Interestingly, one of the most effective ways to integrate these new neurons within the existing network—and therefore to maximize their chance of survival—is to challenge the brain and force neural adaptation (Shors et al. 2012). Learning a new skill and acquiring new knowledge appear to be especially promising in this regard (Gould et al. 1999).

Based on the idea that brain function greatly benefits from physical exercise and that challenging cognitive stimulations ensure these benefits are maintained over time, researchers have proposed that coupling physical and cognitive demands could be especially interesting when targeting cognitive enhancement

Our findings showed that designed sport, an activity specifically tailored to tax working memory and spatial ability by incorporating complex motor coordination in three-dimensional space, outperformed interventions solely focused on either physical or cognitive demands on measures of working memory capacity, spatial ability, and biomarkers of general health, such as resting heart rate and blood pressure (Moreau et al. 2015). This is particularly promising because the cognitive abilities designed sport targeted are critical in many activities—working memory capacity is thought to be a central component of cognition and correlates highly with fluid intelligence (Engle et al. 1999), whereas spatial ability is a significant predictor of success in many academic and professional domains

The field of cognitive training is still in its infancy, and the consequences of combining interventions have yet to be fully understood, but this is undoubtedly a promising venue for research with direct applications to society.

combine cognitive challenges with physical motion should also be encouraged, as they allow creating ecological situations that have the potential to trigger important and transferable cognitive improvement.

In closing, complex motor activities that combine cognitive and physical demands provide a promising direction for the field of cognitive training. Beyond the cognitive benefits, they can induce when designed adequately, the physiological and psychological improvements complex motor activities allow present critical advantages over computerized training regimens, favored thus far. Eventually, the goal is to integrate motor activities durably within the community, so that habits formed in schools can lead to long-term changes in fitness and cognitive health.

The PFC’ s extensive outputs allow for direct control of motor behavior, but they may also influence behavior indirectly by altering perceptual and cognitive representations and influencing the storage and retrieval of long-term memories.

A notable feature of the PFC is its ability to demonstrate sustained activation representing task-relevant information in the absence of sensory input, or even in the face of distracting, irrelevant sensory input

sustained activation of an individual’ s current environmental context and task goals is also necessary for flexible behavior and higher cognitive processing. The PFC likely plays a role in maintenance of these types of information as well. The maintenance of task- and goal-related information is necessary in order to define which new perceptual inputs are irrelevant (i.e., distracting) and which should be encoded and entered into the WM buffer (see also, e.g., Braver & Cohen, 2000).

I will summarize evidence supporting the view (GoldmanRakic, 1995a) that the underlying function of all the regions of the PFC is the creation and maintenance of integrated representations of all relevant information.

The type of information being maintained, rather than the type of processing, however, is the fundamental organizing principle (see Figure 1).

I suggest that attention and cognitive control are not directed actions or specific processes contained within any particular set of brain regions. Rather, what we experience and observe that we call attention and cognitive control are emergent properties dependent on the distributed representation of all types of information, both that available from present perceptual input and the information currently sustained in WM, including contextual and motivational information.

attentional selection is the consequence of biases in perceptual processing that arise directly from the representation in WM of the relative importance of one location, object, or feature over another. In this case, a domain-general attentional selection control process would not be localizable to any particular brain region.