This study investigated the influence of five days of moderate intensity aerobic exercise on the acquisition and consolidation of visual perceptual learning using a motion direction discrimination (MDD) task. The timing of exercise relative to learning was manipulated by administering exercise either before or after perceptual training. Within a matched-subjects design, twenty-seven healthy participants (n = 9 per group) completed five consecutive days of perceptual training on a MDD task under one of three interventions: no exercise, exercise before the MDD task, or exercise after the MDD task. MDD task accuracy improved in all groups over the five-day period, but there was a trend for impaired learning when exercise was performed before visual perceptual training. MDD task accuracy (mean ± SD) increased in exercise before by 4.5 ± 6.5%; exercise after by 11.8 ± 6.4%; and no exercise by 11.3 ± 7.2%. All intervention groups displayed similar MDD threshold reductions for the trained and untrained motion axes after training. These findings suggest that moderate daily exercise does not enhance the rate of visual perceptual learning for an MDD task or the transfer of learning to an untrained motion axis. Furthermore, exercise performed immediately prior to a visual perceptual learning task may impair learning. Further research with larger groups is required in order to better understand these effects.

Background: Measurement of cashew-specific IgE (sIgE) is often used to confirm sensitization but does not reliably diagnose clinical allergy. Ana o 3 is the dominant cashew allergen detected in 75-100% of patients with cashew allergy but not currently used in clinical practice.Objectives: To determine if component-resolved diagnostics using specific IgE to the 2 S albumin from cashew, Ana o 3, improves the accuracy of diagnosing cashew allergy, thereby circumventing the need for an oral food challenge (OFC) in some patients. Methods:A population-based sample of 5276 children was recruited at age 1 year and followed up at age 6 years. Children with positive cashew skin prick test at age 6 underwent an OFC to clarify allergy status. Forty-seven children (mean age 5.02 ± 0.2) (33 cashew-allergic and 14 cashew-tolerant) had cashew sIgE and Ana o 3 sIgE quantified by ImmunoCAP System FEIA.Results: A cutoff of >0.32 kUA/L for Ana o 3 sIgE provided 95% specificity and 90% sensitivity and correctly identified 90% of clinical cashew allergy. At the same specificity, the sensitivity for cashew sIgE (>8.5 kUA/L) was only 26%. Sequential measurement of cashew sIgE followed by Ana o 3 sIgE diagnosed 90% of children with cashew allergy without the need for an OFC. Conclusion:Ana o 3 sIgE testing provides higher diagnostic accuracy than cashew sIgE. Sequential measurement of cashew sIgE followed by Ana o 3 removed the need for a food challenge from 66% down to 12.8% (5-fold) of children compared with cashew sIgE testing alone.

Motor vehicle operation is a complicated task and substantial cognitive resources are required for safe driving. Experimental paradigms examining cognitive workload using driving simulators often introduce secondary tasks, such as mathematical exercises, or utilise simulated in-vehicle information systems. The effects of manipulating the demands of the primary driving task have not been examined in detail using advanced neuroimaging techniques. This study used a manipulation of the simulated driving environment to test the impact of increased driving complexity on brain activity. Fifteen participants drove in two scenarios reflecting common driving environments differing in the amount of vehicular traffic, frequency of intersections, number of buildings, and speed limit restrictions. Functional near infrared spectroscopy was used to quantify changes in cortical activity; fifty-five optodes were placed over the prefrontal and occipital cortices, commonly assessed areas during driving. Compared to baseline, both scenarios increased oxyhaemoglobin in the bilateral prefrontal cortex and cerebral blood volume in the right prefrontal cortex (all p ≤ 0.05). Deoxyhaemoglobin decreased at the bilateral aspects of the prefrontal cortex but overall tended to increase in the medial aspect during both scenarios (both p ≤ 0.05). Cerebral oxygen exchange significantly declined at the lateral aspects of the prefrontal cortex, with a small but significant increase seen in the medial aspect (both p < 0.05). There were no significant differences for oxyhaemoglobin, deoxyhaemoglobin, or cerebral blood volume (all p > 0.05). This study demonstrates that functional near infrared spectroscopy is capable of detecting changes in cortical activity elicited by simulated driving tasks but may be less sensitive to variations in driving workload aggregated over a longer duration.

Purpose We sought to determine the effect of acute severe hypoxia, with and without concurrent manipulation of carbon dioxide (CO2), on complex real-world psychomotor task performance. Methods Twenty-one participants completed a 10-min simulated driving task while breathing room air (normoxia) or hypoxic air (PETO2 = 45 mmHg) under poikilocapnic, isocapnic, and hypercapnic conditions (PETCO2 = not manipulated, clamped at baseline, and clamped at baseline + 10 mmHg, respectively). Driving performance was assessed using a fixed-base motor vehicle simulator. Oxygenation in the frontal cortex was measured using functional near-infrared spectroscopy. Results Speed limit exceedances were greater during the poikilocapnic than normoxic, hypercapnic, and isocapnic conditions (mean exceedances: 8, 4, 5, and 7, respectively; all p ≤ 0.05 vs poikilocapnic hypoxia). Vehicle speed was greater in the poikilocapnic than normoxic and hypercapnic conditions (mean difference: 0.35 km h−1 and 0.67 km h−1, respectively). All hypoxic conditions similarly decreased cerebral oxyhaemoglobin and increased deoxyhaemoglobin, compared to normoxic baseline, while total hemoglobin remained unchanged. Conclusions These findings demonstrate that supplemental CO2 can confer a neuroprotective effect by offsetting impairments in complex psychomotor task performance evoked by severe poikilocapnic hypoxia; however, differences in performance are unlikely to be linked to measurable differences in cerebral oxygenation.

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