No abstract

Behavioral researchers are increasingly conducting their studies online, to gain access to large and diverse samples that would be difficult to get in a laboratory environment. However, there are technical access barriers to building experiments online, and web browsers can present problems for consistent timing-an important issue with reaction-time-sensitive measures. For example, to ensure accuracy and test-retest reliability in presentation and response recording, experimenters need a working knowledge of programming languages such as JavaScript. We review some of the previous and current tools for online behavioral research, as well as how well they address the issues of usability and timing. We then present the Gorilla Experiment Builder (gorilla.sc), a fully tooled experiment authoring and deployment platform, designed to resolve many timing issues and make reliable online experimentation open and accessible to a wider range of technical abilities. To demonstrate the platform's aptitude for accessible, reliable, and scalable research, we administered a task with a range of participant groups (primary school children and adults), settings (without supervision, at home, and under supervision, in both schools and public engagement events), equipment (participant's own computer, computer supplied by the researcher), and connection types (personal internet connection, mobile phone 3G/4G). We used a simplified flanker task taken from the attentional network task (Rueda, Posner, & Rothbart, 2004). We replicated the Bconflict network^effect in all these populations, demonstrating the platform's capability to run reaction-time-sensitive experiments. Unresolved limitations of running experiments online are then discussed, along with potential solutions and some future features of the platform.

To investigate why 3-year-olds have difficulty in switching sorting dimensions, children of 3 and 4 years were tested in one of four conditions on Zelazo's card sort task: standard, sleeve, label and face-up. In the standard condition, children were required to sort blue-truck and red-star cards under either a blue-star or red-truck model card, first by color or shape, and then by the other dimension. Here 3-year-olds sorted correctly until the dimension changed; they continue to sort by the initial dimension. The sleeve condition (placing the sorting cards in an envelope prior to sorting) had little effect. In the label condition, the child labeled the relevant sorting dimension on each trial. Most 3-year-olds succeeded; evidently their labeling helped them refocus their attention, overcoming 'attentional inertia' (the pull to continue attending to the previously relevant dimension). In the face-up condition, attentional inertia was strengthened because sorted cards were left face-up; 4-year-olds performed worse than in the standard condition. We posit that attentional inertia is the core problem for preschoolers on the card sort task.Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously, and accepting both of them. (George Orwell, 1984)

The day-night task requires saying "night" to a picture of the sun and "day" to a picture of the moon. In this investigation of why young children fail at this task, systematic variations of the task were administered to 96 children, half 4 years old and half 4 1/2 years old. Training children on the strategy of chunking the 2 rules into I ("say the opposite"), thus reducing memory load, did not help their performance. What helped was reducing the inhibitory demand by instructing them to say "dog" and "pig" (not "night" and "day") even though memory of 2 rules and inhibiting saying what the pictures represented were still required. Here the response to be activated and the response to be inhibited were unrelated. When the correct response was semantically related to, and the direct opposite of, the to-be-inhibited response, children performed poorly. Inserting a delay between stimulus and response helped even though that delay was filled with distraction. Young children apparently need several seconds to compute the answer on this task. Often they do not take the needed time; when forced to do so, they do well.

Perception involves making sense of a dynamic, multimodal environment. In the absence of mechanisms capable of exploiting the statistical patterns in the natural world, infants would face an insurmountable computational problem. Infant statistical learning mechanisms facilitate the detection of structure. These abilities allow the infant to compute across elements in their environmental input, extracting patterns for further processing and subsequent learning. In this selective review, we summarize findings that show that statistical learning is both a broad and flexible mechanism (supporting learning from different modalities across many different content areas) and input specific (shifting computations depending on the type of input and goal of learning). We suggest that statistical learning not only provides a framework for studying language development and object knowledge in constrained laboratory settings, but also allows researchers to tackle real-world problems, such as multilingualism, the role of ever-changing learning environments, and differential developmental trajectories.