Abstract‘Groupitizing’ refers to the observation that visually grouped arrays can be accurately enumerated much faster than can unstructured arrays. Previous research suggests that visual grouping allows participants to draw on arithmetic abilities and possibly use mental calculations to enumerate grouped arrays quickly and accurately. Here, we address how subitizing might be involved in finding the operands for mental calculations in grouped dot arrays. We investigated whether participants can use multiple subitizing processes to enumerate both the number of dots and the number of groups in a grouped array. We found that these multiple subitizing processes can take place within 150 ms and that dots and groups seem to be subitized in parallel and with equal priority. Implications for research on mechanisms of groupitizing are discussed.

‘Groupitizing’ refers to the observation that visually grouped arrays can be accurately enumerated much faster than unstructured arrays. Previous research on groupitizing suggests that visual grouping allows participants to draw on arithmetic abilities and possibly use mental calculations to enumerate grouped arrays fast and accurately. Here we address how subitizing might be involved in finding the operands for mental calculations in grouped dot arrays. We investigated whether participants could use multiple subitizing processes to enumerate both the number of dots and the number of groups in a grouped array. We found that these multiple subitizing processes can take place within 150ms and that dots and groups seem to be subitized in parallel and with equal priority. Implications for research on mechanisms of groupitizing are discussed.

Objective. To assess whether specific non-communicable diseases are associated with hearing aid adoption in older adults with hearing loss. Design.A cross-sectional, observational study. Study sample.Data was obtained from one of the largest pharmacy-led health and beauty retailers in the United Kingdom. In total, 17,172 older adults were included. Results. Greater odds of adopting hearing aids were associated with being older (Odds ratio[OR]= 1.03; 95% confidence interval [CI]= 1.02, 1.03), having fewer self-reported hearing difficulties (OR= 0.61; 95% CI= 0.58, 0.64), and greater audiometric hearing loss (OR= 1.68; 95% CI= 1.54, 1.83). The odds of adopting hearing aids were lower if individuals self-reported hypertension (OR= 0.87; 95% CI= 0.79, 0.97) and diabetes (OR= 0.83; 95% CI= 0.72, 0.95). Using a decision tree model, self-reported hearing difficulties, audiometric hearing loss, and age were the best combination of variables to differentiate between individuals that did and did not adopt hearing aids.Conclusions. This study demonstrates that hearing aid adoption is lower in older adults with cardiovascular disease risk factors. Thus, there is a need for healthcare professionals to identify older adults living with hearing loss and cardiovascular ill-health, ensuring that they receive appropriate patient-centred support to manage their health.

‘Groupitizing’ refers to the observation that visually grouped arrays can be accurately enumerated much faster than unstructured arrays. Previous research on groupitizing suggests that visual grouping allows participants to draw on arithmetic abilities and possibly use mental calculations to enumerate grouped arrays fast and accurately. Here we address how subitizing might be involved in finding the operands for mental calculations in grouped dot arrays. We investigated whether participants could use multiple subitizing processes to enumerate both the number of dots and the number of groups in a grouped array. We found that these multiple subitizing processes can take place within 150ms and that dots and groups seem to be subitized in parallel and with equal priority. Implications for research on mechanisms of groupitizing are discussed.

Mathematical notation includes a vast array of signs. Most mathematical signs appear to be symbolic, in the sense that their meaning is arbitrarily related to their visual appearance. We explored the hypothesis that mathematical signs with iconic aspects – those which visually resemble in some way the concepts they represent – offer a cognitive advantage over those which are purely symbolic. An early formulation of this hypothesis was made by Christine Ladd in 1883 who suggested that symmetrical signs should be used to convey commutative relations, because they visually resemble the mathematical concept they represent. Two controlled experiments provide the first empirical test of, and evidence for, Ladd’s hypothesis. In Experiment 1 we find that participants are more likely to attribute commutativity to operations denoted by symmetric signs. In Experiment 2 we further show that using symmetric signs as notation for commutative operations can increase mathematical performance.