Biomedical subjects

Alycia M Hund

Publications and source records attributed to Alycia M Hund.

7 recordsLinked to original sources

PubMed2007

What counts as by? Young children's use of relative distance to judge nearbyness.

The authors investigated how 3- and 4-year-old children and adults use relative distance to judge nearbyness. Participants judged whether several blocks were by a landmark. The absolute and relative distance of the blocks from the landmark varied. In Experiment 1, judgments of nearbyness decreased as the distance from the landmark increased, particularly for 4-year-olds and adults. In Experiment 2, 4-year-olds and adults were more likely to judge objects at an intermediate distance as by the landmark when intervening objects were absent than when intervening objects were present. In Experiment 3, participants of all ages were more likely to judge objects at a short distance as by the landmark when intervening objects were absent. Reliance on relative distance to judge nearbyness becomes more systematic and applicable to larger spatial extents across development.

Adult↗

PubMed2005

The stability and flexibility of spatial categories.

Four experiments examined the flexibility and stability with which children and adults organize locations into categories based on their spatiotemporal experience with locations. Seven-, 9-, 11-year-olds, and adults learned the locations of 20 objects in an open, square box. During learning, participants experienced the locations in four spatiotemporally defined groups (i.e., four sets of nearby locations learned together in time). At test, participants attempted to place the objects in the correct locations without the aid of the dots marking the locations. Children and adults displaced the objects toward the corners of the box consistent with the organization they experienced during learning, suggesting that they used spatiotemporal experience to organize the locations into groups. Importantly, the pattern of organization remained the same following a long delay for all four age groups, demonstrating stability. For adults, this organization shifted after a new pattern of spatiotemporal experience was introduced, suggesting that adults' categories based on spatiotemporal experience are quite flexible. Children only exhibited flexibility when the new pattern of spatiotemporal organization was consistent with available perceptual cues, demonstrating that the flexibility with which children organize locations into categories is intimately tied to both remembered and perceptual sources of information.

Adult↗

PubMed2003

Developmental continuity in the processes that underlie spatial recall.

This study investigated whether children's spatial recall performance shows three separable characteristics: (1) biases away from symmetry axes (geometric effects); (2) systematic drift over delays; and (3) biases toward the exemplar distribution experienced in the task (experience-dependent effects). In Experiment 1, the location of one target within each geometric category was varied. Children's responses showed biases away from a midline axis that increased over delays. In Experiment 2, multiple targets were placed within each category at the same locations used in Experiment 1. After removing geometric effects, 6-year-olds'--but not 11-year-olds'--responses were biased toward the average remembered location over learning. In Experiment 3, children responded to one target more frequently than the others. Both 6- and 11-year-olds showed biases toward the most frequent target over learning. These results provide a bridge between the performance of younger children and adults, demonstrating continuity in the processes that underlie spatial memory abilities across development.

Attention↗

PubMed2003

Does information about what things are influence children's memory for where things are?

Two experiments examined how information about what objects are influences memory for where objects are located. Seven-, 9-, and 11-year-old children and adults learned the locations of 20 objects marked by dots on the floor of a box. The objects belonged to 4 categories. In one condition, objects belonging to the same category were located in the same quadrant of the box. In another condition, objects and locations were randomly paired. After learning, participants attempted to replace the objects without the aid of the dots. Children and adults placed the objects in the same quadrant closer together when they were related than when they were unrelated, indicating that object information led to systematic biases in location memory.

Adult↗

PubMed2002

Experiencing nearby locations together in time: the role of spatiotemporal contiguity in children's memory for location.

Three studies investigated how experiencing nearby locations together in time influences memory for location. Seven-, 9-, and 11-year-old children and adults learned 20 object locations in a small-scale space. The space was divided into regions by lines or walls. In Study 1, participants learned the locations either region by region or in a random order. Following learning, participants replaced the objects without the aid of the dots marking the locations and the boundaries subdividing the space. They replaced the objects in any order they chose. After experiencing the locations in random orders during learning, only adults underestimated distances between locations belonging to the same group (i.e., region). Conversely, 9- and 11-year-old children and adults who had experienced the locations region by region during learning underestimated these distances. These findings suggest that experiencing nearby locations together in time increases the weight children assign to categorical information in their estimates of location. Results from Studies 2 and 3 in which participants learned the locations region by region and then replaced the objects region by region (Study 2) or in a random order (Study 3) were similar, highlighting the importance of spatiotemporal cues in memory for location. (c) 2002 Elsevier Science (USA).

Adult↗

PubMed2002

Prototypes and particulars: geometric and experience-dependent spatial categories.

People use geometric cues to form spatial categories. This study investigated whether people also use the spatial distribution of exemplars. Adults pointed to remembered locations on a tabletop. In Experiment 1, a target was placed in each geometric category, and the location of targets was varied. Adults' responses were biased away from a midline category boundary toward geometric prototypes located at the centers of left and right categories. Experiment 2 showed that prototype effects were not influenced by cross-category interactions. In Experiment 3, subsets of targets were positioned at different locations within each category. When prototype effects were removed, there was a bias toward the center of the exemplar distribution, suggesting that common categorization processes operate across spatial and object domains.

Adult↗

PubMedDate not supplied

Delay-induced bias in children's memory for location.

Two experiments examined how imposing a delay between learning and reproducing locations influences children's memory for location. In Experiment 1, ninety-six 7-, 9-, and 11-year-old children and adults learned the locations of 20 objects in an open, square box divided into four regions by opaque walls. During test, participants attempted to place the objects in the correct locations without the aid of the dots that had marked the locations or the boundaries that had divided the space. The test phase began either immediately following learning or following a 12-min delay. As predicted by the Category-Adjustment model, bias toward category centers increased significantly following an intervening delay. Moreover, the magnitude of categorical bias followed a systematic U-shaped developmental pattern. Results from a second study (N = 72) replicated this developmental pattern. Discussion focuses on the implications of these results for understanding how children and adults remember locations.

Bias↗