Increased Brain Activation for Dual Tasking with 70-Days Head-Down Bed Rest

Abstract

Head-down tilt bed rest (HDBR) has been used as a spaceflight analog to simulate the effects of microgravity exposure on human physiology, sensorimotor function, and cognition on Earth. Previous studies have reported that concurrent performance of motor and cognitive tasks can be impaired during space missions. Understanding the consequences of HDBR for neural control of dual tasking may possibly provide insight into neural efficiency during spaceflight. In the current study, we evaluated how dual task performance and the underlying brain activation changed as a function of HDBR. Eighteen healthy men participated in this study. They remained continuously in the 6 • head-down tilt position for 70 days. Functional MRI for bimanual finger tapping was acquired during both single task and dual task conditions, and repeated at 7 time points pre-, during-and post-HDBR. Another 12 healthy males participated as controls who did not undergo HDBR. A widely distributed network involving the frontal, parietal, cingulate, temporal, and occipital cortices exhibited increased activation for dual tasking and increased activation differences between dual and single task conditions during HDBR relative to pre-or post-HDBR. This HDBR-related brain activation increase for dual tasking implies that more neurocognitive control is needed for dual task execution during HDBR compared to pre-and post-HDBR. We observed a positive correlation between pre-to-post HDBR changes in dual-task cost of reaction time and pre-to-post HDBR change in dual-task cost of brain activation in several cerebral and cerebellar regions. These findings could be predictive of changes in dual task processing during spaceflight.

Vestibular brain changes within 70 days of head down bed rest

“…The observed HDBR‐related activation increase parallels our recent findings of dual tasking brain activity during HDBR (Yuan et al, ). We found HDBR‐related immediate increases and cumulative increases in brain activation when participants simultaneously performed a motor and cognitive task.…”

“…Several contrast vectors were set to test the hypothesized relative level of brain activation in each session. For the HDBR subjects, we identified brain areas with two types of HDBR‐related activity change: immediate change and cumulative change (Yuan et al, ). The immediate change was presumed to be sensitive to HDBR status, and was hypothesized to take place shortly after the beginning of HDBR, to maintain during HDBR, and to recover shortly after the finish of HDBR.…”

“…In this study, we hypothesized that functional vestibular brain activity would exhibit neuroplasticity in the HDBR subjects relative to control subjects, and that such changes would correlate with HDBR‐induced declines in postural control. We have also reported that brain activity during cognitive‐motor dual tasking increased with HDBR in the prefrontal cortices, possibly because of reduced neural efficiency during adaptation to the HDBR environment (Yuan et al, ). Thus, we hypothesized here that brain activation in response to vestibular stimulation would increase due to upregulation of sensory input during HDBR relative to control subjects, and that additional brain regions may be recruited in compensation.…”

The Effect of Microgravity-Like Conditions on High-Level Cognition: A Review

“…Nevertheless, we believe that these data represent important steps toward unraveling the differential facets of the interaction between microgravity and cognition. It should also be noted that even in the absence of effects, these data are interesting in light of the changes that had been observed on the central nervous system (De la Torre, 2014; Yuan et al, 2016) and for the potential longterm effects that microgravity may play on cognitive functioning. A recent study points to this direction.…”

A Pedagogical Model for CyberParks

“…Their interaction weakens the results of both. Source: own work based on Pothier et al (2014) and Yuan et al (2016) learner-to-tutors and learning community-to-its learning resources. Learning and knowledge construction is located in the connections and interactions between learners, teachers and resources, and seen as emerging from critical dialogue and enquiry.…”