The Effects of Testimony on Evidence Processing During Category Learning in Children and Adults

• In Event: Poster Session 02
  In Poster Session: PS 02 Topic - Cognitive Processes

Abstract

When acquiring category knowledge, children have two readily available sources of knowledge: their firsthand experience with the world (Carey, 2009) and information provided by others through language, known as testimony (Harris & Koenig, 2006). Testimony specifically using generic language -- statements expressing broad generalizations about a category (e.g. ‘lions have manes) -- is particularly important as children understand these statements to highlight central properties of categories (Gelman, 2003). While we know much about how children learn from testimony, few studies have investigated how testimony interacts with firsthand experience in the process of category learning. The current study examined whether and how these two sources of information interact during a novel category learning task with 5- to 8-year-olds (n=20) and adults (n=49).

In Task 1, we examined how generic testimony impacts firsthand visual experience using an eye-tracking paradigm. Participants learned about physical properties of novel animals through a combination of generic testimony (e.g. “Broosts have stripes”) and firsthand experience with samples containing both testimony-consistent and testimony-inconsistent category members (e.g., broosts with stripes and spots; see Figure 1). Samples varied in whether the target property was high or low in prevalence, making firsthand experience either primarily consistent or inconsistent with testimony. Critically, the order of testimony and firsthand experience was manipulated between participants. Half of participants explored the sample prior to hearing the testimony (baseline condition); half heard the testimony before exploring the sample (testimony first condition).

Results indicated that after receiving generic testimony (e.g. “Broosts have stripes”) children in the testimony first condition spent proportionally more time looking at the unexpected, testimony-inconsistent category members (i.e. broosts with spots) when compared to children in the baseline condition. This effect was primarily driven by low prevalence trials and did not emerge in adults (see Figure 2). These findings suggest that hearing generic testimony may bias children to attend to evidence inconsistent with that testimony, particularly when the testimony and experience conflict.

Task 2 was administered to determine what participants had learned from the testimony and experience and, specifically whether participants integrated the two sources of information or preferentially relied on a single source. Participants were presented with three images: one consistent with the generic testimony, one consistent with firsthand experience, and one indicative of an integration of testimony and experience (see Figure 1). Participants reported which image they believed to be best suited for teaching another individual about the animal. Results showed that participants generally reported learning consistent with a single source of information: Adults varied in whether they relied on testimony (50%) or their own firsthand experience (40%), whereas children relied almost exclusively on testimony (77%). These findings suggest that children and adults may be differentially weighting testimony and firsthand experience during learning.

Overall, this study provides novel insight into the effects of generic testimony on how children and adults explore and learn from their firsthand experiences. Most notably, results suggest that knowledge acquired via generic testimony impacts children’s future information seeking behaviors and may have implications for children’s category learning.

Authors

• Eugene Rohrer, Lehigh University
  Presenting Author

• Amanda C Brandone, Lehigh University
  Non-Presenting Author