Tag: Poster 132

Preliminary Decomposition Study within the Willamette Valley of Oregon: Multi-Regional Comparison and Sharp Force Trauma Effects

Presenter(s): Cheyenne Collins − Anthropology

Faculty Mentor(s): Jeanne McLaughlin

Poster 132

Research Area: Social Science

Funding: Extraordinary Expense Thesis Research Grant from the Robert D. Clark Honors College
Ronald E. McNair Scholars Program

Determining time since death (post-mortem interval or PMI) is an essential part of medico-legal death investigations. PMI can give investigators important information about time of death and may help answer questions about the events leading up to death. The purpose of this study is to collect decompositional data from an understudied region (Oregon), and compare these data to better studied regions such as Tennessee, in order to characterize the effects of regional variation on decomposition and taphonomy. Six pig heads will be exposed to the natural environment in the Willamette Valley of Oregon for sixty days. Three of these pig heads will undergo sharp force trauma infliction (SFT) in order to compare rate of decay with remains that have a singular SFT wound. Stage of decomposition, temperature, precipitation, and preliminary entomological data will be collected throughout the sixty-day observation period. These data will be used to calculate Accumulated Degree Days (ADD); evaluate variation between similar studies involving different North American regions; compare and contrast similar studies within the Willamette Valley of Oregon; and analyze the effects of sharp force trauma (SFT) on decomposition rates and insect activity.

Training on typical items facilitates learning of new concepts

Presenter(s): Wenjia Cao

Faculty Mentor(s): Dasa Zeithamova-Demircan & Caitlin Bowman

Poster 132

Session: Social Sciences & Humanities

Concept learning involves linking pieces of information to a shared category label, like learning that furry creatures that live with humans and bark are called dogs. What factors affect how well people learn new categories? Prior research suggests that people can learn categories either by memorizing individual category members or by averaging across category members to form an abstract representation of the perfect category member, known as the prototype. We reasoned that if people learn categories through memorization, then they should learn better from small training sets, but set size should not affect prototype learning. We also reasoned that if people learn categories through memorization, then they should learn better from training sets where items are distinct from one another (i.e., atypical), but that prototype learning would be facilitated by training on typical items. To test our hypotheses, separate groups of participants underwent category training that varied in the number and typicality of category members. During training, participants saw category members one at a time, guessed which category they belonged to, and were told whether they were right or wrong. Following training, participants were tested on their ability to categorize the training items as well as new examples that they had never seen. We found that people who trained with more typical items learned more quickly and were better at categorizing new examples. Training size did not have a significant influence on learning rate or categorization accuracy. Therefore, our results support the idea that the typicality of training items greatly influences category learning, which is likely because it promotes formation of abstract, prototype category representations.