supported by NSF, NEI, and Vanderbilt University
In the CatLab, we study visual cognition, including visual categorization, visual memory, and visual decision making. We study how objects are perceived and represented by the visual system, how visual knowledge is represented and learned, and how visual decisions are made. We approach these questions using a combination of behavioral experiments, cognitive neuroscience techniques, and computational and neural modeling. One line of work, funded by the National Science Foundation, investigates the temporal dynamics of visual object categorization and perceptual expertise for objects and faces. Another line of work, funded by the National Eye Institute, uses computational modeling of visual decision making to predict behavioral dynamics and neural dynamics.Congratulations to May and Jeff on each being awarded 2016 Young Scientist Travel Awards to the Annual Meeting of the Society for Mathematical Psychology. The award provides $1000 in travel allowance to the society meeting this summer at Rutgers University.
Read MoreWe are looking for outstanding students interested in a Research Experience for Undergraduates (REU) at the CatLab at Vanderbilt University this summer 2016. 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.
Read MoreThe Perceptual Expertise Network celebrated its 30th workshop by inviting current PEN members, previous PEN members, and PEN friends to a day of talks as well as a reunion dinner following the talks. This was held on May 14th, 2015 at the TradeWinds Island Grand Resort in St. Pete Beach, Florida, as a satellite to the annual VSS conference.
Speakers at PEN XXX were:
Thomas Palmeri (Vanderbilt), Opening remarks
Marlene Berhmann (Carnegie Mellon), Never the twain shall meet
Kim Curby (Macquarie University), Are faces super objects? Object-based benefits support holistic perception
Lisa Scott (UMass Amherst), How learning during infancy enhances and constrains brain and behavioral development
Bruno Rossion (University of Louvain), Understanding expertise in face perception with fast periodic visual stimulation
Suzy Scherf (Penn State), Puberty makes us different kinds of face experts
Jim Tanaka (Victoria), Bridging the expertise gap: From the laboratory to the real world
Mike Mack (UT Austin), The evolution of category knowledge: Linking learning models to the dynamics of neural representations
Jennifer Richler (Vanderbilt), Measuring individual differences in high-level vision in a latent-variables framework
Ben Cipollini (UCSD), Exploring anatomy and genetics of cortical asymmetries
Isabel Gauthier (Vanderbilt), 15 years of fMRI studies of expertise
Michael Tarr (Carnegie Mellon), Closing talk
Photos from the workshop can be found here:
http://catlab.psy.vanderbilt.edu/palmeri/public/PEN-XXX/album/index.html
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 MoreThe 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 MoreThe 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 MoreWe 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 MoreWe 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 MoreNew 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 MoreThomas Palmeri from Vanderbilt, Brad Love from University College London, and Brandon Turner from The Ohio State University are co-editing a special issue of the Journal of Mathematical Psychology on Model-Based Cognitive Neuroscience. This special issue aims to explore the growing intersection between cognitive modeling and cognitive neuroscience. Cognitive modeling has a rich history of formalizing and testing hypotheses about cognitive mechanisms within a mathematical and computational language, making exquisite predictions of how people perceive, learn, remember, and decide. Cognitive neuroscience aims to identify neural mechanisms associated with key aspects of cognition, using techniques like neurophysiology, electrophysiology, and structural and functional brain imaging. These two come together in a powerful new approach called model-based cognitive neuroscience, which can both inform model selection and help interpret neural measures. Cognitive models decompose complex behavior into representations and processes and these latent model states are used to explain the modulation of brain states under different experimental conditions. Reciprocally, neural measures provide data that help constrain cognitive models and adjudicate between competing cognitive models that make similar predictions of behavior. For example, brain measures are related to cognitive model parameters fitted to individual participant data, measures of brain dynamics are related to measures of model dynamics, model parameters are constrained by neural measures, model parameters are used in statistical analyses of neural data, or neural and behavioral data are analyzed jointly within hierarchical modeling framework.
Read MoreThe Perceptual Expertise Network will be celebrating our 30th workshop by inviting current PEN members, previous PEN members, and PEN friends to join us for a day of talks as well as a reunion dinner following the talks. This will be held on May 14th, 2015 at the TradeWinds Island Grand Resort in St. Pete Beach, Florida, as a satellite to the annual VSS conference.
Read MoreOur NEI Grant Stochastic Models of Visual Decision Making and Visual Search was just renewed for another four years, through end of 2018.
Read MoreShen, J., & Palmeri, T.J. (in press). The perception of a face is greater than the sum of its parts. Psychonomic Bulletin & Review.
Folstein, J., Palmeri, T.J., Van Gulick, A.B., & Gauthier, I. (in press). Category learning stretches neural representations in visual cortex. Current Directions in Psychological Science.
Shen, J., Mack, M.L., & Palmeri, T.J. (2014). Studying real-world perceptual expertise. Frontiers in Cognition.
Read MoreBraden’s PhD dissertation, Neural Mechanisms of Perceptual Decision Making, has been chosen to receive honorable mention in the 2013-2014 James McKeen Cattell Dissertation competition sponsored by the Psychology Section of the New York Academy of Sciences. The field was highly competitive, with many excellent candidates for the award. His work was highly regarded by the reviewers and by the Steering Committee. The Academy further commended the work of his mentors, Thomas Palmeri and Jeffrey Schall, and the graduate program in Psychological Sciences at Vanderbilt University. In recognition of his noteworthy achievement, he will receive a certificate from the New York Academy of Sciences; his mentors will be similarly recognized. Congratulations Braden!
http://www.nyas.org/awards/13Cattell.aspx
Read MoreThe CatLab has just been awarded a $19,500 supplementary grant from the National Science Foundation for a Research Experience for Undergraduates. Academic year REU students will receive a $3000 stipend per semester. Summer REU students will receive a $5000 stipend, a $1500 housing and meal allowance, and
$250 travel allowance. Interested undergraduates should contact Professor Palmeri at thomas.j.palmeri@vanderbilt.edu for information on how to apply.
Read More