Prolonged functional development of the parahippocampal place area and occipital place area.

Successful navigation of our surroundings is of high environmental relevance and involves processing of the visual scenery. Scene-processing undergoes a major behavioral improvement during childhood. However, possible neural changes that underlie this cognitive development in scene perception are understudied in comparison to other stimulus categories. We used a functional magnetic resonance imaging (fMRI) scene localizer and behavioral recognition and memory tasks in 7-8-year-olds, 11-12-year-olds, and adults to test whether scene-selective areas-the parahippocampal place area (PPA), the retrosplenial cortex (RSC), and the occipital place area (OPA)-show a change in volume and selectivity with age, and whether this change is correlated with behavioral perception and memory performance. We find that children have a smaller PPA and OPA than adults, while the size of RSC does not differ. Furthermore, selectivity for scenes in the PPA and the OPA, but not in the RSC, increases with age. This increase seems to be driven by both increasing responses to preferred stimuli and decreasing responses to non-preferred stimuli. Our findings extend previous knowledge about visual cortex development by unveiling the underlying mechanisms of age-related volume and selectivity increases in the scene network especially elucidating the poorly understood development of the OPA.

Myelin development in visual scene-network tracts beyond late childhood: A multimethod neuroimaging study.

The visual scene-network-comprising the parahippocampal place area (PPA), retrosplenial cortex (RSC), and occipital place area (OPA)-shows a prolonged functional development. Structural development of white matter that underlies the scene-network has not been investigated despite its potential influence on scene-network function. The key factor for white matter maturation is myelination. However, research on myelination using the gold standard method of post-mortem histology is scarce. In vivo alternatives diffusion-weighted imaging (DWI) and myelin water imaging (MWI) so far report broad-scale findings that prohibit inferences concerning the scene-network. Here, we combine MWI, DWI tractography, and fMRI to investigate myelination in scene-network tracts in middle childhood, late childhood, and adulthood. We report increasing myelin from middle childhood to adulthood in right PPA-OPA, and trends towards increases in the left and right RSC-OPA tracts. Investigating tracts to regions highly connected with the scene-network, such as early visual cortex and the hippocampus, did not yield any significant age group differences. Our findings indicate that structural development coincides with functional development in the scene-network, possibly enabling structure-function interactions.

Head motion during fMRI tasks is reduced in children and adults if participants take breaks.

Head motion remains a challenging confound in functional magnetic resonance imaging (fMRI) studies of both children and adults. Most pediatric neuroimaging labs have developed experience-based, child-friendly standards concerning e.g. the maximum length of a session or the time between mock scanner training and actual scanning. However, it is unclear which factors of child-friendly neuroimaging approaches are effective in reducing head motion. Here, we investigate three main factors including (i) time lag of mock scanner training to the actual scan, (ii) prior scan time, and (iii) task engagement in a dataset of 77 children (aged 6-13) and 64 adults (aged 18-35) using a multilevel modeling approach. In children, distributing fMRI data acquisition across multiple same-day sessions reduces head motion. In adults, motion is reduced after inside-scanner breaks. Despite these positive effects of splitting up data acquisition, motion increases over the course of a study as well as over the course of a run in both children and adults. Our results suggest that splitting up fMRI data acquisition is an effective tool to reduce head motion in general. At the same time, different ways of splitting up data acquisition benefit children and adults.

Tracking the Functional Development of the Corpus Callosum in Children Using Behavioral and Evoked Potential Interhemispheric Transfer Times.

Visual functions requiring interhemispheric transfer exhibit a long developmental trajectory up to age 12, which might be constrained by corpus callosum maturation. Here, we use electrophysiological and behavioral crossed-uncrossed differences (CUDs) in a visual Poffenberger paradigm to estimate the interhemispheric transfer time (IHTT)-a measure of corpus callosum maturation-in 7-year-old children and adults. Adults' electrophysiological CUDs were faster than 7-year-olds'. Behavioral CUDs did not differ and proved to be unreliable in a 6-month follow-up test. These findings suggest that the corpus callosum still undergoes development at the age of 7 that can only reliably be traced with neuroscientific methods.

U Can Touch This: How Tablets Can Be Used to Study Cognitive Development.

New technological devices, particularly those with touch screens, have become virtually omnipresent over the last decade. Practically from birth, children are now surrounded by smart phones and tablets. Despite being our constant companions, little is known about whether these tools can be used not only for entertainment, but also to collect reliable scientific data. Tablets may prove particularly useful for collecting behavioral data from those children (1-10 years), who are, for the most part, too old for studies based on looking times and too young for classical psychophysical testing. Here, we analyzed data from six studies that utilized touch screen tablets to deliver experimental paradigms in developmental psychology. In studies 1 and 2, we employed a simple sorting and recall task with children from the ages of 2-8. Study 3 (ages 9 and 10) extended these tasks by increasing the difficulty of the stimuli and adding a staircase-based perception task. A visual search paradigm was used in study 4 (ages 2-5), while 1- to 3-year-olds were presented with an extinction learning task in study 5. In study 6, we used a simple visuo-spatial paradigm to obtain more details about the distribution of reaction times on touch screens over all ages. We collected data from adult participants in each study as well, for comparison purposes. We analyzed these data sets in regard to four metrics: self-reported tablet usage, completeness of data, accuracy of responses and response times. In sum, we found that children from the age of two onwards are very capable of interacting with tablets, are able to understand the respective tasks and are able to use tablets to register their answers accordingly. Results from all studies reiterated the advantages of data collection through tablets: ease of use, high portability, low-cost, and high levels of engagement for children. We illustrate the great potential of conducting psychological studies in young children using tablets, and also discuss both methodological challenges and their potential solutions.

Stress improves task processing efficiency in dual-tasks.

Psychological stress has attracted much interest as a potential modulator of response control processes. However, especially in dual-task situations, the effect of psychological stress is less understood. In the current study we investigated these effects. "Thirty six" healthy young male participants were exposed to stress applying the socially evaluated cold pressor task (SECPT) or a control condition. Afterwards they participated in a psychological refractory period (PRP) paradigm comprising two tasks (a "tone task" and a "letter task"). With the PRP task, four different stimulus onset asynchronies (SOA) were realized separating the tone from the letter task. The results show that stress improves task processing efficiency in dual-tasks. Stressed participants showed a reduced PRP effect (i.e., shorter response times), which was especially prominent in the short SOAs conditions (16 and 133ms). The analysis of the response times suggests that stress increases dual-tasking performance by modulating the efficiency to process the different tasks and not because 'cognitive flexibility' and switching between task components at the bottleneck is altered. Increases in processing efficiency in dual-tasks were predictable by means of individual salivary cortisol levels.