CATLAB

category laboratory

Navigation Menu

Akash Umakantha wins Founder’s Medal

Posted on May 8, 2015

The Founder’s Medal is the top honor given to a graduate of Vanderbilt University. Cornelius Vanderbilt’s gifts to the university included endowment of this award, given since 1877 for first honors in each graduating class. Akash Umakantha, who has been working in the CatLab since the end of his freshman year, is this year’s recipient from the School of Engineering at Vanderbilt. Congratulations Akash!

Akash Umakantha, from West Chester, Ohio, is Founder’s Medalist for the School of Engineering. He graduated with a bachelor of engineering in electrical and biomedical engineering. Umakantha has been a researcher at Cold Spring Harbor Laboratory, the Vanderbilt Radiation Effects and Reliability Group and the Vanderbilt Department of Psychology. He has presented his research on models of decision-making at two international conferences. Working in Professor of Psychology Tom Palmeri’s laboratory after freshman year, he learned about mathematical models of decision-making and how to simulate complex mathematical equations on a computer. That experience inspired him to pursue an academic career in neuroscience and scientific computing. Umakantha served as an engineering tutor, and he volunteered in a 6th grade classroom through Vanderbilt Student Volunteers for Science. He is a member of engineering honor society Tau Beta Pi. Next fall, Umakantha will attend Carnegie Mellon University to pursue doctoral studies in neural computation and machine learning.

Read More


Jennifer Richler co-winner of the Bob Fox Award of Excellence in Post-Doctoral Research

Posted on Apr 21, 2015

The Bob Fox Award of Excellence in Post-Doctoral Research is granted to post-doctoral fellows in the Department of Psychology at Vanderbilt who have demonstrated outstanding achievement in research; it is named in honor of Robert “Bob” Fox for his essential role in guiding the evolution of Vanderbilt’s Psychology Department over a five-decade period starting in the mid-60s.

Jenn earned her PhD at Vanderbilt with Isabel Gauthier and Thomas Palmeri and has continued on at Vanderbilt as a post-doctoral fellow. She previously won the Nunnally Dissertation Award and the Pat Burns Graduate Student Research Award from the department. She has 30 peer-reviewed publications and is an Associate Editor at JEP:General. She also spearheaded the PeePs (Particularly Exciting Experiments in Psychology) newsletter that highlights research published in the six experimental psychology journals from APA.

Congratulations, Jenn!

Read More


May Shen co-winner of The William F. Hodges Teaching Assistant Award

Posted on Apr 21, 2015

The William F. Hodges Teaching Assistant Award recognizes outstanding achievement as a teaching assistant by a graduate student in the Department of Psychology at Vanderbilt. William Hodges was an undergraduate and a graduate student at Vanderbilt in the 1960s. After his untimely death in 1992, family and friends established the William F. Hodges Teaching Assistant Award at Vanderbilt to honor outstanding teaching assistants in the department.

May is a third year graduate student in the CatLab. She has completed a Certificate in College Teaching from the Center for Teaching and has TAed for a wide array of courses in the department, including PSY208 (Principles of Experimental Design), PSY209 (Quantitative Methods), and PSY225 (Cognitive Psychology); this semester, she is TAing for a statistics course in Psychology and Human Development. Adriane Seiffert, for whom May TAed in PSY208 and PSY209, noted that her work was “exemplary in both courses”, and that students commented that “she was responsive and helpful – gave exact answers to questions”, “conveyed the material in a way she knew would be effective, logical and memorable”. Geoff Woodman, for whom May TAed in PSY225, noted that she “jumped on a week’s worth of lectures when given the opportunity.”

Congratulations, May!

Read More


New paper in Journal of Experimental Psychology: General

Posted on Mar 24, 2015

We have a new paper in press:

Mack, M.L., & Palmeri, T.J. (in press). The dynamics of categorization: Unraveling rapid categorization. Journal of Experimental Psychology: General. [PDF]

We explore a puzzle of visual object categorization: Under normal viewing conditions, you spot something as a dog fastest, but at a glance, you spot it faster as an animal. During speeded category verification, a classic basic-level advantage is commonly observed (Rosch, Mervis, Gray, Johnson, & Boyes-Braem, 1976), with categorization as a dog faster than as an animal (superordinate) or Golden Retriever (subordinate). A different story emerges during ultra-rapid categorization with limited exposure duration (<30ms), with superordinate categorization faster than basic or subordinate categorization (Thorpe, Fize, & Marlot, 1996). These two widely cited findings paint contrary theoretical pictures about the time course of object categorization, yet no study has previously investigated them together. Over five experiments, we systematically examined two experimental factors that could explain the qualitative difference in categorization across the two paradigms: exposure duration and category trial context. Mapping out the time course of object categorization by manipulating exposure duration and the timing of a post-stimulus mask revealed that brief exposure durations favor superordinate-level categorization, but with more time a basic-level advantage emerges. But this superordinate advantage was modulated significantly by target category trial context. With randomized target categories, the superordinate advantage was eliminated; and with “blocks” of only four repetitions of superordinate categorization within an otherwise randomized context, the advantage for the basic-level was eliminated. Contrary to some theoretical accounts that dictate a fixed priority for certain levels of abstraction in visual processing and access to semantic knowledge, the dynamics of object categorization are flexible, depending jointly on the level of abstraction, time for perceptual encoding, and category context.

Read More


Research Experience for Undergraduates (REU)

Posted on Feb 9, 2015

We are looking for outstanding students interested in a Research Experience for Undergraduates (REU) at the CatLab at Vanderbilt University this summer 2015. Our REU is part of an NSF-funded project entitled Perceptual Categorization in Real-World Expertise. This project uses online behavioral experiments to understand the temporal dynamics of perceptual expertise, measuring and manipulating the dynamics of object recognition and categorization at different levels of abstraction and assessing how those dynamics vary over measured levels of expertise, using computational models to test hypotheses about expertise mechanisms. Students have opportunities to work on projects ranging from the development of online experiments, development of analysis routines, and development and testing of computational models. This REU is especially appropriate for students interested in applying to graduate programs in psychology, vision science, cognitive science, or neuroscience. The REU provides a $5000 summer stipend, $500 per week for ten weeks; an additional $150 per week helps offsets the cost of housing and meals; a $250 travel allowance is also provided. REUs are restricted to undergraduate students currently enrolled in a degree program and must be U.S. citizens, U.S. nationals, or permanent residents of the United States. Undergraduates who are students at Vanderbilt may have the opportunity to continue the REU into the 2015-16 academic year. Click on READ MORE for further details on the REU and how to apply.

Read More


New Papers

Posted on Jan 28, 2015

New papers in press:

Palmeri, T.J., & Mack, M.L. (in press). How experimental trial context affects perceptual categorization. Frontiers in Psychology.

Logan, G.D., Yamaguchi, M., & Schall, G.D., & Palmeri, T.J. (in press). Inhibitory control in mind and brain 2.0: A blocked-input model of saccadic countermanding. Psychological Review.

Richler, J.J., Palmeri, T.J., & Gauthier, I. (in press). Holistic processing does not require configural variability. Psychonomic Bulletin & Review.

Read More