Neural and Behavioral Outcomes Differ Following Equivalent Bouts of Motor Imagery or Physical Practice.

Despite its reported effectiveness for the acquisition of motor skills, we know little about how motor imagery (MI)-based brain activation and performance evolves when MI (the imagined performance of a motor task) is used to learn a complex motor skill compared to physical practice (PP). The current study examined changes in MI-related brain activity and performance driven by an equivalent bout of MI- or PP-based training. Participants engaged in 5 days of either MI or PP of a dart-throwing task. Brain activity (via fMRI) and performance-related outcomes were obtained using a pre/post/retention design. Relative to PP, MI-based training did not drive robust changes in brain activation and was inferior for realizing improvements in performance: Greater activation in regions critical to refining the motor program was observed in the PP versus MI group posttraining, and relative to those driven via PP, MI led only to marginal improvements in performance. Findings indicate that the modality of practice (i.e., MI vs. PP) used to learn a complex motor skill manifests as differences in both resultant patterns of brain activity and performance. Ultimately, by directly comparing brain activity and behavioral outcomes after equivalent training through MI versus PP, this work provides unique knowledge regarding the neural mechanisms underlying learning through MI.

Parent-reported health outcomes at preschool age in preterm survivors: a population-based cohort study.

OBJECTIVE: Literature on health status (HS) and health-related quality of life of preterm survivors at preschool age is sparse. Further, little is known about the relationship between parent-reported HS outcomes and standardised neurodevelopmental outcomes measured in preterm survivors at preschool age. Our objective was to evaluate parent-reported child HS outcomes and their relationship to neurodevelopmental outcomes at 36 months of age in very preterm survivors. DESIGN: Prospective population-based cohort study. SETTING: Perinatal follow-up programme. PATIENTS: Infants <31 weeks' gestational age born from 2014 to 2016. OUTCOME MEASURES: Parents completed the Health Status Classification System for Pre-School Children questionnaire at 36 months. At the same age, neurodevelopmental assessments were completed to determine neurodevelopmental impairment (NDI). NDI was categorised as none, 'mild' or 'significant' (moderate or severe cerebral palsy, Bayley Scales of Infant and Toddler Development - Third Edition <70, blind or required hearing aid). RESULTS: Of 118 children, 87 (73.7%) parents reported their child had an HS concern (mild: 61 (51%); moderate: 16 (13.6%); and severe: 10 (8.5%)). Mild and significant NDIs were observed in 17 (14.4%) and 14 (11.9%) children, respectively. For the 14 (12%) children with significant NDI, 7 (50.0%) parents reported severe and 4 (28.6%) reported moderate concerns. Conversely, for 26 (22%) children with parent-reported moderate to severe concerns, 11 (42.3%) met the criteria for significant NDI. There was a moderate positive correlation between parental concern and NDI status (Spearman correlation=0.46, p<0.0001). CONCLUSIONS: Parental HS concerns only moderately correlated with the NDI status. Of the 12% of children with significant NDI, only half of the parents reported severe HS concerns.

Non Breast-Milk-Fed Very Preterm Infants Are at Increased Risk of Iron Deficiency at 4-6-Months Corrected Age: A Retrospective Population-Based Cohort Study.

Iron supplementation is routinely recommended for breast-milk-fed preterm infants. However, the Canadian Pediatric Society recommends no additional iron supplementation for preterm infants fed primarily with iron-rich formula. Other pediatric societies don't provide specific guidance on supplemental iron for formula-fed preterm infants. This study investigated how feeding type influences iron status of very preterm infants at 4-6-months corrected age (CA). A retrospective cohort study was conducted using a population-based database on all very preterm infants (<31 weeks gestational age) born in Nova Scotia, Canada from 2005-2018. Information about feeding type, iron intake from formula, supplemental iron therapy and iron status at 4-6-months CA was extracted. Iron deficiency (ID) was defined as serum ferritin <20 and <12 µg/L at 4-and 6-months CA, respectively. Of 392 infants, 107 were "breast-milk-fed" (exclusively or partially) and 285 were "not breast-milk-fed" (exclusively fed with iron-rich formula) at 4-6-months CA. Total daily iron intake was higher in the non-breast-milk-fed group (2.6 mg/kg/day versus 2.0 mg/kg/day). Despite this, 36.8% of non-breast-milk-fed infants developed ID versus 20.6% of breast-milk-fed infants. ID is significantly more prevalent in non-breast-milk-fed infants than breast-milk-fed infants despite higher iron intake. This suggests the need to revisit recommendations for iron supplementation in non-breast-milk-fed preterm infants.

Imagined movement accuracy is strongly associated with drivers of overt movement error and weakly associated with imagery vividness.

Theories of motor imagery conflict in their account of what happens during an imagined movement, with some suggesting that movement is simulated while others suggest it involves creating and elaborating upon an internal representation of the movement. Here we report evidence that imagery involves the simulation of a movement and that it varies in accuracy. Two groups of participants performed a motor task focused on challenging movement execution either overtly or via motor imagery. Overt performance was used to model expected performance given required movement characteristics (i.e., speed, complexity, familiarity), which was then compared with self-reported accuracy during imagery. Movement characteristics had a large effect on self-reported accuracy compared with a small effect of imagery vividness. Self-reported accuracy improved across trials with familiar movements compared with novel movements in a similar manner for each group. The complexity of the imagined movement did not influence movement time during imagery or overt trials, further suggesting that imagined movements are simulated rather than abstractly represented. Our results therefore support models of motor imagery that involve the simulation of a movement and its viability, which may be the basis of imagery-based motor learning. (PsycInfo Database Record (c) 2022 APA, all rights reserved).