Analyzing a Single Nucleotide Polymorphism (SNP) in Schizophrenia: A meta-analysis approach

Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task—primarily involving left hemisphere structures—would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18–80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry—an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right—increased significantly under dual-task conditions in those aged 40–59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control

Increasing cognitive load attenuates right arm swing in healthy human walking

Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task-primarily involving left hemisphere structures-would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18-80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry-an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right-increased significantly under dual-task conditions in those aged 40-59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control

Selective autophagy and Golgi quality control in Drosophila

The LIR motif-docking site (LDS) of Atg8/LC3 proteins is essential for the binding of LC3-interacting region (LIR)-containing proteins and their subsequent degradation by macroautophagy/autophagy. In our recent study, we created a mutated LDS site in Atg8a, the Drosophila homolog of Atg8/LC3 and found that LDS mutants accumulate known autophagy substrates and have reduced lifespan. We also conducted quantitative proteomics analyses and identified several proteins that are enriched in the LDS mutants, including Gmap (Golgi microtubule-associated protein). Gmap contains a LIR motif and accumulates in LDS mutants. We showed that Gmap and Atg8a interact in a LIR-LDS dependent manner and that the Golgi size and morphology are altered in Atg8a-LDS and Gmap-LIR motif mutants. Our findings highlight a role for Gmap in the regulation of Golgiphagy

Presentations

Text spelling out one of four colours (red, green, yellow and blue) presented at pseudorandom intervals using Powerpoint 2010 (Microsoft Corp., Redmond, WA, USA). The duration of each stimulus was between 600 and 1400ms. To avoid potential entrainment of temporal gait parameters and to encourage constant attention, stimulus duration was adjusted so that no more than two sequential stimuli had a duration within 200ms of that of the previous stimulus, although mean stimulus frequency was maintained at 1Hz over the trial

FINAL_DATA

Final data in xls. format. Please see readme for usage

Supplementary Table 1 from Increasing cognitive load attenuates right arm swing in healthy human walking

Mean ± SEM of gait parameters under three walking conditions on a treadmill; normal walking (no additional cognitive load), walking while performing a congruent Stroop task and walking while performing an incongruent Stroop task. Step length is the distance in the progression axis from heel strike to ipsilateral heel strike. Step width is the distance in the lateral axis from heel strike to contralateral heel strike. Phase dispersion is calculated as the point in the time normalised gait cycle at which the coordinated event occurs during the cycle of the second limb expressed as a percentage of the latter, with maximal arm protraction taken as the index event for arm swing and toe-off taken as that for stepping. Foot clearance is reported as the distance in the vertical axis of the toe marker from the treadmill at the point of ipsilateral mid swing. * indicates significant change to baseline walking condition, † indicates significant change between incongruent and congruent Stroop task condition (linear mixed model, p=0.05). CoV; coefficient of variation