Does Cogmed working-memory training (CWMT) work? Independent groups of reviewers have come to what appears to be starkly different conclusions to this question, causing somewhat of a debate within scientific and popular media. Here, various studies, meta-analyses, and reviews of the Cogmed research literature will be considered to provide an overview of our present understanding regarding the effects of CWMT. These will particularly be considered in light of two recent critical reviews published by Melby-Lervåg and Hulme ( 2013 ) and Shipstead, Hicks, and Engle ( 2012 ) and their arguments and conclusions assessed against current available evidence. Importantly we describe how the conclusions drawn by Melby-Lervåg and Hulme appear to contradict their own findings. In fact, the results from their meta-analysis show highly significant effects of working-memory (WM) training on improving visuospatial WM and verbal WM (both ps < .001). In addition, analyses of long-term follow-ups show that effects on visuospatial WM remain significant over time (again at p < .001). Thus, the analyses show that WM is indeed improved using WM training, and the highest effect sizes are achieved using CWMT (compared with other training programs). We also conclude that there is current evidence from several studies using different types of outcome measures that shows attention can be improved following CWMT. In a little more than a decade, there is evidence that suggests that Cogmed has a significant impact upon visual-spatial and verbal WM, and these effects generalize to improved sustained attention up to 6 months. We discuss the evidence for improvements in academic abilities and conclude that although some promising studies are pointing to benefits gained from CWMT, more controlled studies are needed before we can make strong and specific claims on this topic. In conclusion, we find that there is a consensus in showing that WM capacity and attention is improved following CWMT. Due to the importance of WM and attention in everyday functioning, this is, on its own, of great potential value.

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The effects of green manured field pea (Pisum sativum L.), low-input (LI) wheat (Triticum aestivum L.) (seeding rate of 40 kg/ha and 85 kg/ha of diammonium phosphate), and high-input (HI) wheat (seeding rate of 100 kg/ha, 85 kg/ha of diammonium phosphate, and 180 kg/ha of urea) sown as rotation crops after cotton on soil quality; cotton growth, yield and nutrient uptake; and gross margins ($AU/ha and $AU/ML of irrigation water) were evaluated from 1993 to 1998 in an irrigated Vertosol in the central-west of New South Wales. Soil quality indicators monitored were aggregate stability (dispersion index), compaction (air-filled porosity), soil resilience to structural destruction (as geometric mean diameter of soil aggregates formed after puddling and drying of soil), exchangeable cations, calcium carbonate, nitrate-N, pH, organic C, development of arbuscular mycorrhiza (AM), and incidence of cotton root diseases (black root rot). In comparison with wheat, field pea increased soil nitrate-N levels during the early stages of the experiment and formed smaller aggregates after puddling and drying, but it was ineffective in ameliorating soil compaction. In contrast wheat was very effective in ameliorating soil compaction. Nitrate-N values under wheat–cotton rotations increased with time such that after 4 years they were similar to that under the field pea–cotton rotation. Soil chemical fertility indicators such as organic C, pH, EC, and exchangeable cations were not affected consistently by either wheat or field pea, whereas minimum tillage, retention of crop residues, and cropping phase (i.e. rotation crop or cotton) affected them more. A net decrease in organic C and an increase in EC was observed with time in all treatments. By sowing either field pea or wheat, the mycorrhizal colonisation of cotton roots was improved. Black root rot incidence was increased 3-fold by sowing field pea, but was not significantly affected by wheat. Cotton lint yield was unaffected by rotation crop, although profitability shown as gross margins/ha and gross margins/ML irrigation water were greater with wheat compared with field pea. Gross margins/ha were in the order HI wheat > LI wheat > field pea, and gross margins/ML irrigation water were in the order LI wheat > HI wheat > field pea. In terms of ameliorating soil compaction, minimising black root incidence, and maximising returns to the cotton grower, wheat is a better rotation crop than field pea. The decision to apply fertiliser and sow wheat at a higher seeding rate will depend on whether land or water is the major limiting factor.

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