Gut estimates: Pregnant women adapt to changing possibilities for squeezing through doorways

Possibilities for action depend on the fit between the body and the environment. Perceiving what actions are possible is challenging because the body and the environment are always changing. How do people adapt to changes in body size and compression? In Experiment 1, we tested pregnant women monthly over the course of pregnancy to determine whether they adapted to changing possibilities for squeezing through doorways. As women gained belly girth and weight, previously passable doorways were no longer passable, but women’s decisions to attempt passage tracked their changing abilities. Moreover, their accuracy was equivalent to that of non-pregnant adults. In Experiment 2, non-pregnant adults wore a “pregnancy pack” that instantly increased the size of their bellies and judged whether doorways were passable. Accuracy in “pregnant” participants was only marginally worse than that of actual pregnant women, suggesting that participants adapted to the prosthesis during the test session. In Experiment 3, participants wore the pregnancy pack and gauged passability before and after attempting passage. Judgments were grossly inaccurate prior to receiving feedback. Findings indicate that experience facilitates perceptual-motor recalibration for certain types of actions

The Development of Action Perception

Contains fulltext : 221871.pdf (preprint version ) (Closed access)When newly born into this world, there is an overwhelming multitude of things to learn, ranging from learning to speak to learning how to solve a mathematical equation. Amidst this abundance, action perception is developing already in the first months of life. Why would learning about others' actions be among the first items to acquire? What is the relevance of action perception for young infants? Part of the answer probably lies in the strong dependence on others. Newborn human infants need caretakers even for fulfilling their basic needs. Weak neck muscles make it hard for them to lift up their head, and most of their movements come across as uncoordinated. Clearly, getting themselves a drink or dressing themselves is not part of their repertoire. Their reliance on their caregivers makes these caregivers and their actions important for the young infant. Seeing that the caregiver responds to their calls can already reduce some of the stress that comes with being so dependent. As such, it is helpful for an infant to learn to distinguish different actions of the caregiver. Not only are the caregivers' actions focused on the infant's physical needs, but also on helping the infant to regulate her emotions. Parents typically comfort a baby by softly rocking them, and by talking and smiling to them. Social interaction between caregiver and infant thus starts immediately after birth, and these interactions help them to bond. In the context of social interaction, it is useful to be able to distinguish a smile from a frown. Interpreting the facial actions of others is vital to successful communication. Moreover, in the period in which infants are still very limited in their own actions, observing others' actions forms a main resource for learning about the world. Making sense of others' actions is therefore of central importance already during early development

Performance on the Stroop predicts treatment compliance in cocaine-dependent individuals.

Treatment dropout is a problem of great prevalence and stands as an obstacle to recovery in cocaine-dependent (CD) individuals. Treatment attrition in CD individuals may result from impairments in cognitive control, which can be reliably measured by the Stroop color-word interference task. The present analyses contrasted baseline performance on the color-naming, word-reading, and interference subtests of the Stroop task in CD subjects who completed a cocaine treatment trial (completers: N=50) and those who dropped out of the trial before completion (non-completers: N=24). A logistic regression analysis was used to predict trial completion using three models with the following variables: the Stroop task subscale scores (Stroop model); the Hamilton depression rating scale (HDRS) scores (HDRS model); and both the Stroop task subscale scores and HDRS scores (Stroop and HDRS model). Each model was able to significantly predict group membership (completers vs non-completers) better than a model based on a simple constant (HDRS model p=0.02, Stroop model p=0.006, and Stroop and HDRS model p=0.003). Models using the Stroop preformed better than the HDRS model. These findings suggest that the Stroop task can be used to identify cocaine-dependent subjects at risk for treatment dropout. The Stroop task is a widely available, reliable, and valid instrument that can be easily employed to identify and tailor interventions of at risk individuals in the hope of improving treatment compliance