Robert M. Nosofsky

Distinguished Professor
Department of Psychological and Brain Sciences
Program in Cognitive Science
Indiana University, Bloomington

812-855-2534 (office)
812-855-8416 (lab)
812-855-4691 (fax)



Department of Psychological and Brain Sciences
1101 E. Tenth St.
Bloomington, IN 47405

Robert Nosofsky is winner of the 2012 Howard Crosby Warren Medal, the oldest and one of the most prestigious awards in the field of experimental psychology.  He is currently looking for new graduate students and undergraduate students to join his lab!


Research Interests

My research is organized around the development and testing of formal mathematical models of perceptual category learning and representation. A main theme of the research involves studying relations between categorization and other fundamental cognitive processes, including old-new recognition memory, the development of automaticity, and decision making. Current research projects include: 1) modeling the time course of categorization and recognition judgments, 2) examining the basis for neural and behavioral dissociations between categorization and memory performance, 3) distinguishing among exemplar-based and logical-rule-based accounts of category representation, and 4) studying the properties of visual working memory.


Curriculum Vitae


Online Papers

Donkin, C., Tran, S.C., & Nosofsky, R.M. (2014). Landscaping analyses of the ROC predictions of discrete-slots and signal-detection models of visual working memory. Attention, Perception & Psychophysics. DOI 10.3758/s13414-013-0561-7

Donkin, C., Nosofsky, R.M., Gold, J., & Shiffrin, R.M. (2014). Verbal labeling, gradual decay, and sudden death in visual short-term memory. Psychonomic Bulletin & Review. DOI 10.3758/s13423-014-0675-5

Nosofsky, R. M., Cox, G. E., Cao, R., & Shiffrin, R. M. (2014). An exemplar-familiarity model predicts short-term and long-term probe recognition across diverse forms of memory search. Journal of Experimental Psychology: Learning, Memory, and Cognition. Advance online publication. http://dx.doi.org/10.1037/xlm0000015

Nosofsky, R. M., Cao, R., Cox, G. E., & Shiffrin R. M. (2014). Familiarity and categorization processes in memory search. Cognitive Psychology, 75, 97-129.

Nosofsky, R.M., & Palmeri, T.J. (in press). An exemplar-based random-walk model of categorization and recognition. In J.R. Busemeyer, J.T. Townsend, Z.J. Wang, & A Eidels (Eds.), Oxford Handbook of Computational and Mathematical Psychology.

Donkin, C., Nosofsky, R.M., Gold, J.M., & Shiffrin, R.M. (2013). Discrete-slots models of visual working-memory response times. Psychological Review, 120, 873-902. [Supplementary materials]

Donkin, C., & Nosofsky, R.M. (2012). The structure of short-term memory scanning: an investigation using response time distribution models. Psychonomic Bulletin & Review, 19, 363-394.

Nosofsky, R.M., Denton, S.E., Zaki, S.R., Murphy-Knudsen, A.F., & Unverzagt, F.W. (2012). Studies of implicit prototype extraction in patients with mild cognitive impairment and early Alzheimer's disease. Journal of Experimental Psychology: Learning, Memory, and Cognition, 38, 860-880.

Little, D.R., Nosofsky, R.M., Donkin, C., & Denton, S.E. (in press). Logical rules and the classification of integral-dimension stimuli. Journal of Experimental Psychology: Learning, Memory, and Cognition.

Nosofsky, R.M., Little, D.R., & James, T.W. (2012). Activation in the neural network responsible for categorization and recognition reflects parameter changes. Proceedings of the National Academy of Sciences, 109, 333-338. [Supporting Information]

Donkin, C., & Nosofsky, R.M. (2012). A power law model of psychological memory strength in short- and long-term recognition. Psychological Science, 23, 625-634.

Nosofsky, R.M., Little, D.R., Donkin, C., & Fific, M. (2011). Short-term memory scanning viewed as exemplar-based categorization. Psychological Review, 118, 280-315.

Fific, M., Little, D. R., & Nosofsky, R. M.(2010). Logical-rule models of classification response times: A synthesis of mental-architecture, random-walk, and decision-bound approaches. Psychological Review, 117, 309-348. [Supplemental files]

Gureckis, T. M., James, T. W., & Nosofsky, R. M.(2011). Re-evaluating dissociations between implicit and explicit category learning: An event-related fMRI study. Journal of Cognitive Neuroscience, 23, 1697-1709.

Little, D. R., Nosofsky, R. M., & Denton, S. E. (2011). Response-time tests of logical-rule models of categorization. Journal of Experimental Psychology: Learning, Memory, and Cognition, 37, 1-27.

Nosofsky, R. M., & Little, D. R.(2010). Classification response times in probabilistic rule-based category structures: Contrasting exemplar-retrieval and decision-bound models. Memory & Cognition, 38, 916-927. [Supplemental files]

Fific, M., Nosofsky, R. M., & Townsend, J. T. (2008). Information-Processing Architectures in Multidimensional Classification: A Validation Test of the Systems Factorial Technology. Journal of Experimental Psychology: Human Perception and Performance, 34, 356-375.

Nosofsky, R. M., & Bergert, F. B. (2007). Limitations of Exemplar Models of Multi-Attribute Probabilisitic Inference. Journal of Experimental Psychology: Learning, Memory, and Cognition, 33, 999-1019.

Bergert, F. B., & Nosofsky, R. M. (2007). A Response-Time Approach to Comparing Generalized Rational and Take-the-Best Models of Decision Making. Journal of Experimental Psychology: Learning, Memory, and Cognition, 33, 107-129.

Zaki, S. R., & Nosofsky, R. M. (2007). A high-distortion enhancement effect in the prototype-learning paradigm: Dramatic effects of category learning during test. Memory & Cognition, 35, 2088-2096.

Stanton, R. D., & Nosofsky, R. M. (2007). Feedback interference and dissociations of classification: Evidence against the multiple-learning-systems hypothesis. Memory & Cognition, 35, 1747-1758.

Nosofsky, R. M., & Stanton, R. D. (2006). Speeded Old–New Recognition of Multidimensional Perceptual Stimuli: Modeling Performance at the Individual-Participant and Individual-Item Levels. Journal of Experimental Psychology: Human Perception and Performance, 32, 314-334

Knapp, B. R., Nosofsky, R. M., & Busey, T. A. (2006). Recognizing distinctive faces: A hybrid-similarity exemplar model account. Memory & Cognition, 34, 877-889.

Nosofsky, R. M., & Kantner, J. (2006). Exemplar similarity, study-list homogeneity, and short-term perceptual recognition. Memory & Cognition, 34, 112-124.

Nosofsky, R. M., Stanton, R. D., & Zaki, S. R. (2005). Procedural interference in perceptual classification: Implicit learning or cognitive complexity? Memory & Cognition, 33, 1256-1271.

Nosofsky, R. M., & Stanton, R. D. (2005). Speeded classification in a probabilistic category structure: Contrasting exemplar-retrieval, decision-boundary, and prototype models. Journal of Experimental Psychology: Human Perception and Performance, 31(3), 608-629.

Zaki, S. R., & Nosofsky, R. M. (2004). False prototype enhancement effects in dot pattern categorization. Memory & Cognition, 32(3), 390-398.

Zaki, S. R., Nosofsky, R. M., Stanton, R. D., & Cohen, A. L. (2003). Prototype and exemplar accounts of category learning and attentional allocation: A reassessment. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29(6), 1160-1173.

Zaki, S. R., Nosofsky, R. M., Jessup, N. M., & Unversagt, F. W. (2003). Categorization and recognition performance of a memory-impaired group: Evidence for single-system models. Journal of the International Neuropsychological Society, 9(3), 394-406.

Nosofsky, R. M., & Zaki, S. R. (2003). A hybrid-similarity exemplar model for predicting distinctiveness effects in perceptual old-new recognition. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29(6), 1194-1209.

Cohen, A. L., & Nosofsky, R. M. (2003). An extension of the exemplar-based random-walk model to separable-dimension stimuli. Journal of Mathematical Psychology, 47(2), 150-165.

Treat, T. A., McFall, R. M., Viken, R. J., Nosofsky, R. M., MacKay, D. B., & Kruschke, J. K. (2002). Assessing clinically relevant perceptual organization with multidimensional scaling techniques. Psychological Assessment, 14(3), 239-252.

Nosofsky, R. M., & Zaki, S. R. (2002). Exemplar and prototype models revisited: Response strategies, selective attention, and stimulus generalization. Journal of Experimental Psychology: Learning, Memory, and Cognition, 28(5), 924-940.

Viken, R. J., Treat, T. A., Nosofsky, R. M., McFall, R. M., & Palmeri, T. J. (2002). Modeling individual differences in perceptual and attentional processes related to bulimic symptoms. Journal of Abnormal Psychology, 111(4), 598-609.

Stanton, R. D., Nosofsky, R. M., & Zaki, S. R. (2002). Comparisons between exemplar similarity and mixed prototype models using a linearly separable category structure. Memory & Cognition, 30(6), 934-944.

Palmeri, T. J., & Nosofsky, R. M. (2001). Central tendencies, extreme points, and prototype enhancement effects in ill-defined perceptual categorization. Quarterly Journal of Experimental Psychology: Human Experimental Psychology, 54A(1), 197-235.

Zaki, S. R., & Nosofsky, R. M. (2001). Exemplar accounts of blending and distinctiveness effects in perceptual old-new recognition. Journal of Experimental Psychology: Learning, Memory, and Cognition, 27(4), 1022-1041.

Zaki, S. R., & Nosofsky, R. M. (2001).A single-system interpretation of dissociations between recognition and categorization in a task involving object-like stimuli. Cognitive, Affective & Behavioral Neuroscience, 1(4), 344-359.

Cohen, A. L., Nosofsky, R. M., & Zaki, S. R. (2001). Category variability, exemplar similarity, and perceptual classification. Memory & Cognition, 29(8), 1165-1175.

Nosofsky, R. M., & Johansen, M. K. (2000). Exemplar-based accounts of multiple-system phenomena in perceptual categorization. Psychonomic Bulletin & Review, 7(3), 375-402.

Nosofsky, R. M. (2000).Exemplar representation without generalization? Comment on Smith and Minda's (2000) Thirty categorization results in search of a model. Journal of Experimental Psychology: Learning, Memory, and Cognition, 26(6), 1735-1743.

Cohen, A. L., & Nosofsky, R. M. (2000). An exemplar-retrieval model of speeded same-different judgments. Journal of Experimental Psychology: Human Perception & Performance, 26(5), 1549-1569.

Nosofsky, R. M., & Alfonso-Reese, L. A. (1999).Effects of similarity and practice on speeded classification response times and accuracies: Further tests of an exemplar-retrieval model. Memory & Cognition, 27(1), 78-93.

Nosofsky, R. M., & Palmeri, T. J. (1998). A rule-plus-exception model for classifying objects in continuous-dimension spaces. Psychonomic Bulletin & Review, 5(3), 345-369.

Nosofsky, R. M., & Zaki, S. R. (1998). Dissociations between categorization and recognition in amnesic and normal individuals: An exemplar-based interpretation. Psychological Science, 9(4), 247-255.

Nosofsky, R. M. (1998). Selective attention and the formation of linear decision boundaries: Reply to maddox and ashby (1998). Journal of Experimental Psychology: Human Perception & Performance, 24(1), 322-339.

Nosofsky, R. M., & Palmeri, T. J. (1997). An exemplar-based random walk model of speeded classification. Psychological Review, 104(2), 266-300.

Nosofsky, R. M., & Palmeri, T. J. (1997). Comparing exemplar-retrieval and decision-bound models of speeded perceptual classification. Perception & Psychophysics, 59(7), 1027-1048.

Nosofsky, R. M. (1997). An exemplar-based random-walk model of speeded categorization and absolute judgment. In A. A. J. Marley (Ed.), Choice, decision, and measurement: Essays in honor of R. Duncan Luce (pp. 347-365). Mahwah, NJ, US: Lawrence Erlbaum Associates, Publishers.

McKinley, S. C., & Nosofsky, R. M. (1996). Selective attention and the formation of linear decision boundaries. Journal of Experimental Psychology: Human Perception & Performance, 22(2), 294-317.

Nosofsky, R. M., & Palmeri, T. J. (1996). Learning to classify integral-dimension stimuli. Psychonomic Bulletin & Review, 3(2), 222-226.

Palmeri, T. J., & Nosofsky, R. M. (1995). Recognition memory for exceptions to the category rule. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21(3), 548-568.

McKinley, S. C., & Nosofsky, R. M. (1995). Investigations of exemplar and decision bound models in large, ill-defined category structures. Journal of Experimental Psychology: Human Perception & Performance, 21(1), 128-148.

Shiffrin, R. M., & Nosofsky, R. M. (1994). Seven plus or minus two: A commentary on capacity limitations. Psychological Review, 101(2), 357-361.

Nosofsky, R. M., Palmeri, T. J., & McKinley, S. C. (1994). Rule-plus-exception model of classification learning. Psychological Review, 101(1), 53-79.

Nosofsky, R. M., Gluck, M. A., Palmeri, T. J., & McKinley, S. C. (1994). Comparing models of rule-based classification learning: A replication and extension of Shepard, Hovland, and Jenkins (1961). Memory & Cognition, 22(3), 352-369.

Nosofsky, R. M., Kruschke, J. K., & McKinley, S. C. (1992). Combining exemplar-based category representations and connectionist learning rules. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18(2), 211-233.

Nosofsky, R. M., & Smith, J. K. (1992). Similarity, identification, and categorization: Comment on Ashby and Lee (1991). Journal of Experimental Psychology: General, 121(2), 237-245.

Nosofsky, R. M. (1992). Exemplars, prototypes, and similarity rules. In A. F. Healy, & S. M. Kosslyn (Eds.), Essays in honor of William K. Estes, vol. 1: From learning theory to connectionist theory; vol. 2: From learning processes to cognitive processes (pp. 149-167). Hillsdale, NJ, England: Lawrence Erlbaum Associates, Inc.

Nosofsky, R. M. (1992). Exemplar-based approach to relating categorization, identification, and recognition. In F. G. Ashby (Ed.), Multidimensional models of perception and cognition. Scientific psychology series (pp. 363-393). Hillsdale, NJ, England: Lawrence Erlbaum Associates, Inc.

Nosofsky, R. M. (1992). Similarity scaling and cognitive process models. Annual Review of Psychology, 43, 25-53.

Shin, H. J., & Nosofsky, R. M. (1992). Similarity-scaling studies of dot-pattern classification and recognition. Journal of Experimental Psychology: General, 121(3), 278-304.

Nosofsky, R. M. (1991). Relation between the rational model and the context model of categorization. Psychological Science, 2(6), 416-421.

Nosofsky, R. M. (1991). Typicality in logically defined categories: Exemplar-similarity versus rule instantiation. Memory & Cognition, 19(2), 131-150.

Nosofsky, R. M. (1991). Tests of an exemplar model for relating perceptual classification and recognition memory. Journal of Experimental Psychology: Human Perception & Performance, 17(1), 3-27.

Nosofsky, R. M. (1991). Stimulus bias, asymmetric similarity, and classification. Cognitive Psychology, 23(1), 94-140.

Nosofsky, R. M. (1990). Relations between exemplar-similarity and likelihood models of classification. Journal of Mathematical Psychology, 34(4), 393-418.

Nosofsky, R. M., Clark, S. E., & Shin, H. J. (1989). Rules and exemplars in categorization, identification, and recognition. Journal of Experimental Psychology: Learning, Memory, and Cognition, 15(2), 282-304.

Nosofsky, R. M. (1989). Further tests of an exemplar-similarity approach to relating identification and categorization. Perception & Psychophysics, 45(4), 279-290.

Nosofsky, R. M. (1988). Similarity, frequency, and category representations. Journal of Experimental Psychology: Learning, Memory, and Cognition, 14(1), 54-65.

Nosofsky, R. M. (1988). Exemplar-based accounts of relations between classification, recognition, and typicality. Journal of Experimental Psychology: Learning, Memory, and Cognition, 14(4), 700-708.

Nosofsky, R. M. (1988). On exemplar-based exemplar representations: Reply to Ennis (1988). Journal of Experimental Psychology: General, 117(4), 412-414.

Nosofsky, R. M. (1987). Attention and learning processes in the identification and categorization of integral stimuli. Journal of Experimental Psychology: Learning, Memory, and Cognition, 13(1), 87-108.

Nosofsky, R. M. (1986). Attention, similarity, and the identification-categorization relationship. Journal of Experimental Psychology: General, 115(1), 39-57.

Nosofsky, R. (1985). Overall similarity and the identification of separable-dimension stimuli: A choice model analysis. Perception & Psychophysics, 38(5), 415-432.

Nosofsky, R. M. (1985). Luce's choice model and Thurstone's categorical judgment model compared: Kornbrot's data revisited. Perception & Psychophysics, 37(1), 89-91.

Nosofsky, R. M. (1984). Choice, similarity, and the context theory of classification. Journal of Experimental Psychology: Learning, Memory, and Cognition, 10(1), 104-114.

Nosofsky, R. M. (1983). Shifts of attention in the identification and discrimination of intensity. Perception & Psychophysics, 33(2), 103-112.

Nosofsky, R. M. (1983). Information integration and the identification of stimulus noise and criterial noise in absolute judgment. Journal of Experimental Psychology: Human Perception & Performance, 9(2), 299-309.

Luce, R. D., Nosofsky, R. M., Green, D. M., & Smith, A. F. (1982). The bow and sequential effects in absolute identification. Perception & Psychophysics, 32(5), 397-408.