Avian Visual Cognition

Huber
 Home Page

   __________
VII. References

     Astley, S., & Wasserman, E. A. (1992). Categorical discrimination and generalization in pigeons: all negative stimuli are not created equal. Journal of Experimental Psychology: Animal Behavior Processes, 18, 193-207. 

    Attneave, F. (1957). Transfer of experience with a class-schema to identification-learning of patterns and shapes. Journal of Experimental Psychology, 54, 81-88. 

    Aydin, A., & Pearce, J. M. (1994). Prototype effects in categorization by pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 20, (pp. 264-277). 

    Bhatt, R. S., Wasserman, E. A., Reynolds, W. F., & Knauss, K. S. (1988). Conceptual behavior in pigeons: Categorization of both familiar and novel examples from four classes of natural and artificial stimuli. Journal of Experimental Psychology: Animal Behavior Processes, 14, 219-234. 

    Blough, D. S. (1985). Discrimination of letters and random dot patterns by pigeons and humans. Journal of Experimental Psychology: Animal Behavior Processes, 11, 261-280. 

    Bruce, V., Burton, A. M., Hanna, E., Healey, P., Mason, O., Coombes, A., Fright, R., & Linney, A. (1993). Sex discrimination: how do we tell the difference between male and female faces? Perception, 22, 131-152. 

   Bruner, J. S., Goodnow, J., & Austin, F. (1956). A study of thinking. New York, NY: Wiley. 

    Brunswik, E., & Reiter, L. (1937). Eindrucks-Charaktere schematisierter Gesichter. Zeitschrift für Psychologie, 142, 67-134. 

    Cabe, P. A. (1976). Transfer of discrimination from solid objects to pictures by pigeons: a test of theoretical models of pictorial perception. Perception and Psychophysics, 19, 545-550. 

    Cerella, J. (1979). Visual classes and natural categories in the pigeon. Journal of Experimental Psychology: Human Perception and Performance, 5, 68-77. 

    Cerella, J. (1980). The pigeon's analysis of pictures. Pattern Recognition, 12, 1-6. 

    Cerella, J. (1982). Mechanisms of concept formation in the pigeon. In D. J. Ingle, M. A. Goodale, & R. J. W. Mansfield (Eds.), Analysis of visual behavior (pp. 242-259). Cambridge, MA.: MIT Press. 

     Cerella, J. (1986). Pigeons and perceptrons. Pattern Recognition, 19, 431-438.

     Cerella, J. (1990). Pigeon pattern perception: limits on perspective invariance. Perception, 19, 141-159.

     Chater, N., & Heyes, C. (1994). Animal concepts: Content and discontent. Mind & Language, 9, 209-246. 

     Cook, R. G. (1992b). Dimensional organization and texture discrimination in pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 18, 354-363. 

     Cook, R. G. (1992c). The visual perception and processing of textures by pigeons. In W. K. Honig & J. G. Fetterman (Eds.), Cognitive aspects of stimulus control (pp. 279-299). Hillsdale, NJ: Lawrence Erlbaum. 

     Cook, R. G. (1993a). Gestalt contributions to visual texture discriminations by pigeons. In T. Zentall (Ed.), Animal cognition: A tribute to Donald A. Riley (pp. 251-269). Hillsdale, NJ: Erlbaum. 

     Cook, R. G., Cavoto, K. K., & Cavoto, B. R. (1995). Same/different texture discrimination and concept learning by pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 21, 253-260. 

     Cook, R. G., Cavoto, K. K., & Cavoto, B. R. (1996). Mechanisms of multidimensional grouping, fusion, and search. Animal Learning & Behavior, 24, 150-167. 

     Cook, R. G., Wright, A. A. & Kendrick, D. F. (1990). Visual categorization by pigeons. In M. L. Commons, R. J. Herrnstein, S. Kosslyn & D. Mumford (Eds.), Quantitative analysis of behavio: Vol. 8. Behavioral approaches to pattern recognition and concept formation (pp. 187-214). Hillsdale, NJ: Lawrence Erlbaum.

     Cumming, W. W. (1966). A bird's eye glimpse of men and machines. In R. Ulrich, T. Stachnik, & J. Mabry (Eds.), Control of human behavior. Glenview, IL: Scott, Foresman. 

     D'Amato, M. R., & Van Sant, P. (1988). The person concept in monkeys (Cebus apella). Journal of Experimental Psychology: Animal Behavior Processes, 14, 43-55. 

     Delius, J. D. (1992). Categorical discrimination of objects and pictures by pigeons. Animal Learning & Behavior, 20, 301-311. 

     Delius, J. D., Jitsumori, M., & Siemann, M. (2000). Stimulus equivalencies through discrimination reversals. In C. Heyes & L. Huber (Eds.), The evolution of cognition (pp. 103-122). Cambridge, MA: MIT Press.

     Dennis, I., Hampton, J. A., & Lea, S. E. G. (1973). New problem in concept formation. Nature, 243, 101-102. 

     Edwards, C. A., & Honig, W. K. (1987). Memorization and "feature selection" in the acquisition of natural concepts in pigeons. Learning and Motivation, 18, 235-260. 

     Fersen, L. V., & Delius, J. D. (1989). Long-term retention of many visual patterns by pigeons. Ethology, 82, 141-155. 

     Fersen, L. V., & Lea, S. E. G. (1990). Category discrimination by pigeons using five polymorphous features. Journal of the Experimental Analysis of Behavior, 54, 69-84. 

     Fetterman, J. G. (1996). Dimensions of stimulus complexity. Journal of Experimental Psychology: Animal Behavior Processes, 22, 3-18.

     Fried, L. S., & Holyoak, K. J. (1984). Induction of category distributions: A framework for classification learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 10, 234-257. 

     Gluck, M. A. (1991). Stimulus generalization and representation in adaptive network models of category learning. Psychological Science, 2, 50-55. 

     Gluck, M. A., & Bower, G. H. (1988). From conditioning to category learning: An adaptive network model. Journal of Experimental Psychology: General, 117, 227-247. 

     Goldman, D., & Homa, D. (1977). Integrative and metric properties of abstracted information as a function of category discriminability, instance variability, and experience. Journal of Experimental Psychology: Human Perception and Performance, 3, 375-385. 

     Greene, S. L. (1983). Feature memorization in pigeon concept formation. In M. L. Commons, R. J. Herrnstein, & A. R. Wagner (Eds.), Quantitative analysis of behavior, Vol. 4: Discrimination processes (pp. 209-229). Cambridge, MA: Ballinger. 

     Hanson, H. M. (1959). Effects of discrimination training on stimulus generalization. Journal of Experimental Psychology, 58, 321-334. 

     Haralick, R. M. (1979). Statistical and structural approaches to texture. Proceedings of the IEEE, 67, 786-804. 

     Harnad, S. (Ed.). (1987). Categorical perception. The groundwork of cognition. Cambridge, U.K.: Cambridge University Press.

     Herrnstein, R. J. (1979). Acquisition, generalization, and discrimination reversal of a natural concept. Journal of Experimental Psychology: Animal Behavior Processes, 5, 116-129. 

    Herrnstein, R. J. (1984). Objects, categories, and discriminative stimuli. In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds.), Animal cognition (pp. 233-261). Hillsdale, NJ: Lawrence Erlbaum Associates. 

     Herrnstein, R. J. (1985). Riddles of natural categorization. In L. Weiskrantz (Ed.), Animal Intelligence: Vol. 7. (pp.129-144). Oxford, U.K.: Clarendon Press. 

     Herrnstein, R. J. (1990). Levels of stimulus control: A functional approach. Cognition, 37, 133-166. 

    * Herrnstein, R. J., & De Villiers, P. A. (1980). Fish as a natural category for people and pigeons. In G. H. Bower (Ed.), The psychology of learning and motivation: Vol. 14.  (pp. 59-95). New York, NY: Academic Press. 

     Herrnstein, R. J., & Loveland, D. H. (1964). Complex visual concept in the pigeon. Science, 146, 549-551. 

     Herrnstein, R. J., Loveland, D. H., & Cable, C. (1976). Natural concepts in pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 2, 285-302

    Homa, D. (1984). On the nature of categories. In G. H. Bower (Ed.), The Psychology of Learning and Motivation: Advances in research and theory. Vol. 18. (pp. 49-94). San Diego, CA: Academic Press.

     Homa, D., & Chambliss, D. (1975). The relative contribution of common and distinctive information on the abstraction from ill-defined categories. Journal of Experimental Psychology: Human Perception and Performance, 1, 351-359. 

     Honig, W. K., & Stewart, K. E. (1988). Pigeons can discriminate locations presented in pictures. Journal of the Experimental Analysis of Behavior, 50, 541-551

     Honig, W. K., & Urcuioli, P. J. (1981). The legacy of Guttman and Kalish (1956): 25 years of research on stimulus generalization. Journal of the Experimental Analysis of Behavior, 26, 405-445. 

     Huber, L. (1991). Gestalten, Konzepte und nonverbale Begriffe. Eine vergleichende Untersuchung täubischer und menschlicher Kategorisierung. Unpublished Dissertation, Universität Wien. 

     Huber, L. (1995). On the biology of perceptual categorization. Evolution and Cognition, 1, 121-138. 

     Huber, L. (1998). Perceptual categorization as the groundwork of animal cognition. In C. Taddei-Ferretti & C. Musio (Eds.), Downward processing in the perception representation mechanism (pp. 287-293). Hong Kong: World Scientific. 

     Huber, L. (1999). Generic perception: Open-ended categorization of natural classes. Cahiers de Psychologie Cognitive - Current Psychology of Cognition,18, 845-888.

     Huber, L., Aust, U., Michelbach, G., Ölzant, S., Loidolt, M., & Nowotny, R. (1999). Limits on symmetry conceptualization in pigeons. The Quarterly Journal of Experimental Psychology, 52B, 351-379.

     Huber, L., & Lenz, R. (1993). A test of the linear feature model of polymorphous concept discrimination with pigeons. The Quarterly Journal of Experimental Psychology, 46B, 1-18. 

     Huber, L., & Lenz, R. (1996). Categorisation of prototypical stimulus classes by pigeons. The Quarterly Journal of Experimental Psychology, 49B, 111-133. 

     Huber, L., Troje, N. F., Loidolt, M., Aust, U., & Grass, D. (2001). Natural categorization through first-order feature learning in pigeons. Manuscript submitted for publication.  

     Jitsumori, M. (1993). Category discrimination of artificial polymorphous stimuli based on feature learning. Journal of Experimental Psychology: Animal Behavior Processes, 19, 244-254. 

     Jitsumori, M., & Ohkubo, O. (1996). Orientation discrimination and categorization of photographs of natural objects by pigeons. Behavioural Processes, 38, 205-226. 

     Jitsumori, M., & Yoshihara, M. (1997). Categorical discrimination of human facial expressions by pigeons: A test of the linear feature model. The Quarterly Journal of Experimental Psychology, 50B, 253-267. 

     Julesz, B. (1981). Textons, the elements of texture perception. Nature, 290, 91-97. 

     Julesz, B., & Kröse, B. (1988). Features and spatial filters. Nature, 333, 302-303. 

     Keller, F. S., & Schoenfeld, W. N. (1950). Principles of psychology. New York, NY: Appleton-Century-Crofts. 

     Kruschke, J. K. (1992). ALCOVE: An exemplar-based connectionist model of category learning. Psychological Review, 99, 22-44

     Lea, S. E. G. (1984). In what sense do pigeons learn concepts? In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds.), Animal cognition (pp. 263-276). Hillsdale, NJ: Lawrence Erlbaum. 

     Lea, S. E. G., & Harrison, S. N. (1978). Discrimination of polymorphous stimulus sets by pigeons. The Quarterly Journal of Experimental Psychology, 30, 521-537. 

     Lea, S. E. G., Lohmann, A., & Ryan, C. M. E. (1993). Discrimination of five-dimensional stimuli by pigeons: Limitations of feature analysis. The Quarterly Journal of Experimental Psychology, 46, 19-42. 

     Lea, S. E. G., & Ryan, C. M. E. (1983). Feature analysis of pigeons' acquisition of concept discrimination. In M. L. Commons, R. J. Herrnstein, & A. R. Wagner (Eds.), Quantitative analysis of behavior: Vol. 4. Discrimination processes (pp. 263-276). Cambridge, MA: Ballinger. 

     Lea, S. E. G., & Ryan, C. M. E. (1990). Unnatural concepts and the theory of concept discrimination in birds. In M. L. Commons, R. J. Herrnstein, S. Kosslyn, & D. Mumford (Eds.), Quantitative Analysis of Behavior: Vol. 8. Behavioral approaches to pattern recognition and concept formation  (pp. 165-185). Cambridge, MA: Ballinger. 

    Loidolt, M., Troje, N. F., Huber, L., Aust, U., & Fieder, M. (1997). The role of texture and shape in complex visual perception in pigeons. In M. Taborsky & B. Taborsky (Eds.), Advances in Ethology: Contributions to the XXV International Ethological Conference: Vol. 32. (pp. 92). Berlin, GER: Blackwell. 

     Lubow, R. E. (1974). High-order concept formation in the pigeon. Journal of the Experimental Analysis of Behavior, 21, 475-483. 

     Lumsden, E. A. (1977). Generalization of an operant response to photographs and drawings/silhouettes of a three-dimensional object at various orientations. Bulletin of the Psychonomic Society, 10, 405-407. 

     Mackintosh, N. J. (1995). Categorization by people and pigeons: The twenty-second Bartlett Memorial Lecture. The Quarterly Journal of Experimental Psychology, 48B, 193-214. 

     Mackintosh, N. J. (2000). Abstraction and discrimination. In C. Heyes & L. Huber (Eds.), Evolution of cognition (pp. 123-141). Cambridge, MA: MIT Press. 

      Marler, P. R. (1982). Avian and primate communication: The problem of natural categories. Neuroscience and Biobehavioral Reviews, 6, 87-94

     Marr, D. (1982). Vision. A computational investigation into the human representation and processing of visual information. San Francisco, CA: Freeman. 

     McLaren, I. P. L., Kaye, H., & Mackintosh, N. J. (1989). An associative theory of the representation of stimuli: Applications to perceptual learning and latent inhibition. In R. G. M. Morris (Ed.), Parallel distributed processing. Implications for psychology and neurobiology (pp. 102-130). Oxford, U.K.: Clarendon Press. 

     Medin, D. L., & Schaffer, M. M. (1978). Context theory of classification learning. Psychological Review, 85, 207-238. 

     Medin, D. L., & Smith, E. E. (1984). Concepts and concept formation. In M. R. Rosenzweig (Ed.), Annual Review of Psychology. Vol. 35. (pp. 113-138). Palo Alto, CA: Annual Reviews. 

     Monen, J., Brenner, E., & Reynaerts, J. (1998). What does a pigeon see in a Picasso?. Journal of the Experimental Analysis of Behavior, 69, 223-226

     Morgan, M. J., Fitch, M. D., Holman, M. D., & Lea, S. E. G. (1976). Pigeons learn the concept of an 'A'. Perception, 5, 57-66.

     Mostofsky, D. (Ed.). (1965). Stimulus generalization. Stanford, CA: Stanford University Press. 

     Neisser, U. (Ed.). (1987). Concepts and conceptual development. Ecological and intellectual factors in categorization. Cambridge, U.K.: Cambridge University Press. 

     Neumann, P. G. (1977). Visual prototype formation with discontinuous representation of dimensions of variability. Memory & Cognition, 5, 187-197. 

     Nilsson, N. J. (1965). Learning machines. New York, NY: McGraw-Hill. 

     Osorio, D. (1996). Symmetry detection by categorization of spatial phase, a model. Proceedings of the Royal Society of London, B, 263, 105-110. 

     Pearce, J. M. (1987). A model for stimulus generalization for Pavlovian conditioning. Psychological Review, 94, 61-73. 

     Pearce, J. M. (1988). Stimulus generalization and the acquisition of categories by pigeons. In L. Weiskrantz (Ed.), Thought without language (pp. 132-152). Oxford, U. K.: Oxford University Press. 

     Pearce, J. M. (1989). The acquisition of an artificial category by pigeons. The Quarterly Journal of Experimental Psychology, 41B, 381-406. 

     Pearce, J. M. (1991). The acquisition of concrete and abstract categories in pigeons. In L. Dachowski & C. F. Flaherty (Eds.), Current topics in animal learning (pp. 141-164). Hillsdale, NJ: Lawrence Erlbaum. 

     Pearce, J. M. (1994). Discrimination and categorization. In N. J. Mackintosh (Ed.), Animal learning and cognition: Vol. 9. (pp.109-134). 

     Pearce, J. M. (1997). Animal learning and cognition. An introduction. Hove, U. K.: Psychology Press. 

     Pentland, A. P. (1984). Fractal-based description of natural scenes. IEEE Transactions on Pattern Analysis and Machine Intelligence, 6, 661-674. 

     Pietrewicz, A. T., & Kamil, A. C. (1977). Visual detection of cryptic prey by blue jays (Cyanocitta christata). Science, 195, 580-582. 

     Poole, J., & Lander, D. G. (1971). The pigeon's concept of pigeon. Psychonomic Science, 25, 157-158. 

     Porter, D., & Neuringer, A. (1984). Music discriminations by pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 10, 138-148. 

     Posner, M. I. (1969). Abstraction and the process of recognition. In G. H. Bower & J. T. Spence (Eds.), The psychology of learning and motivation. Vol. 3. New York, NY: Academic Press. 

     Posner, M. I., & Keele, S. W. (1968). On the genesis of abstract ideas. Journal of Experimental Psychology, 77, 353-363

     Premack, D. (1976). Intelligence in ape and man. Hillsdale, NJ: Lawrence Erlbaum.

     Premack, D. (1983a). Animal cognition. Annual Review of Psychology, 34, 351-362. 

     Purtle, R. B. (1973). Peak shift: A review. Psychological Bulletin, 80, 408-421. 

      Real, P. G., Iannazzi, R., Kamil, A. C., & Heinrich, B. (1984). Discrimination and generalization of leaf damage by blue jays (Cyanocitta cristata). Animal Learning & Behavior, 12, 202-208. 

     Reed, S. K. (1972). Pattern recognition and categorization. Cognitive Psychology, 3, 382-407. 

     Rescorla, R., & Wagner, A. R. (1972). A theory of Pavlovian conditioning. Variations in the effectiveness of reinforcement and nonreinforcement. In A. H. Black & W. F. Prokasy (Eds.), Classical conditioning II: Current research and theory . New York, NY: Appleton-Century-Crofts. 

     Rilling, M. (1977). Stimulus control and inhibitory processes. In W. K. Honig & J. E. R. Staddon (Eds.), Handbook of operant behavior (pp. 432-480). Englewood Cliffs, NJ: Prentice Hall. 

     Ristau, C. A. & Robbins, D. (1982). Language in the great apes: A critical review. In J. S. Rosenblatt; P. A. Hinde, C. Beer & M.C. Busnel (Eds.), Advances in the study of behavior: Vol. 12. New York, NY: Academic Press.

     Roberts, W. A., & Mazmanian, D. S. (1988). Concept learning at different levels of abstraction by pigeons, monkeys, and people. Journal of Experimental Psychology: Animal Behavior Processes, 14, 247-260. 

     Rosch, E. (1978). Principles of categorization. In E. Rosch & B. B. Lloyd (Eds.), Cognition and categorization (pp. 27-48). Hillsdale, NJ: Lawrence Erlbaum. 

     Ryle, G. (1949). The concept of mind. London, U.K.: Hutchinson. 

     Schrier, A. M., Angarella, R. & Povar, M. L. (1984). Studies of concept formation by stumptailed monkeys: Concepts humans, monkeys and letter A. Journal of Experimental Psychology: Animal Behavior Processes, 10, 564-584.

     Schrier, A. M., & Brady, P. M. (1987). Categorization of natural stimuli by monkeys (Macaca mulatta): Effects of stimulus set size and modification of exemplars. Journal of Experimental Psychology: Animal Behavior Processes, 13, 136-143

     Schyns, P., Goldstone, R. L., & Thilbaut, J.P. (1998). The development of features in object concepts. Behavioral and Brain Sciences, 21, 1-54. 

     Shanks, D. R. (1991). Categorization by a connectionist network. Journal of Experimental Psychology: Learning, Memory, and Cognition, 17, 433-443. 

     Shepard, R. N. (1987). Toward a universal law of generalization for psychological science. Science, 237, 1317-1323. 

     Shepard, R. N., Hovland, C. I., & Jenkins, H. M. (1961). Learning and memorization of classifications. Psychological Monographs: General and Applied, 75(13), 1-42. 

     Skinner, B. F. (1935). The generic nature of the concepts of stimulus and response. Journal of General Psychology, 12, 40-65. 

     Skinner, B. F. (1960). Pigeons in a pelican. American Psychologist, 15, 28-37. 

     Smith, E. E., & Medin, D. L. (1981). Categories and concepts. Cambridge, MA: Harvard University Press. 

     Spence, K. W. (1937). The differential response in animals to stimuli varying within a single dimension. Psychological Review, 44, 430-444. 

     Steele, K. M. (1990). Configural processes in pigeon perception. In M. L. Commons, R. J. Herrnstein, S. Kosslyn & D. Mumford (Eds.), Quantitative analysis of behavior: Vol. 8. Behavioral approaches to pattern recognition and concept formation (pp. 111-125). Cambridge, MA: Ballinger.

     Thompson, E., Palacios, A., & Varela, F. J. (1992). Ways of coloring: comparative color vision as a case study for cognitive science. Behavioral and Brain Sciences, 15, 1-74. 

     Tinbergen, N. (1951). The study of instinct. Oxford, U.K.: Clarendon.

     Troje, N., & Buelthoff, H. (1996). Face recognition under varying pose: The role of texture and shape. Vision Research, 36, 1761-1771. 

     Troje, N., & Vetter, T. (1998). Representations of human faces. In C. Taddei-Ferretti & C. Musio (Eds.), Downward processing in the perception representation mechanism. London, U. K.: World Scientific. 

     Troje, N. F., Huber, L., Loidolt, M., Aust, U., & Fieder, M. (1998). Correspondence-based representations of complex object classes: The role of visual texture and shape in classification experiments with pigeons. Verhandlungen der Deutschen Zoologischen Gesellschaft, 91, 1. 

     Troje, N. F., Huber, L., Loidolt, M., Aust, U., & Fieder, M. (1999). Categorical learning in pigeons: the role of texture and shape in complex static stimuli. Vision Research, 39, 353-366. 

     Uexküll, J. V. (1939). Tier und Umwelt. Zeitschrift für Tierpsychologie, 2, 101-114. 

     Varela, F. J., Palacios, A. G., & Goldsmith, T. H. (1993). Color vision of birds. In H. P. Zeigler & H.-J. Bischof (Eds.), Vision, Brain, and Behavior in Birds (pp. 77-98). Cambridge, MA: MIT Press. 

     Vaughan, W. J. & Greene, S. L. (1983). Acquisition of absolute discrimination in pigeons. In M. L. Commons, R. J. Herrnstein & A. R. Wagner (Eds.), Quantitative analysis of behavior: Vol. 4. Discrimination processes (pp. 231-238). Cambridge, MA: Ballinger.

     Vaughan, W. J., & Greene, S. L. (1984). Pigeon visual memory capacity. Journal of Experimental Psychology: Animal Behavior Processes, 10, 256-271. 

     Verhave, Z. (1966). The pigeon as a quality control inspector. In R. Ulrich, T. Stachnik, & J. Mabry (Eds.), Control of Human Behavior . Glenview, IL: Scott, Foresman. 

     Vetter, T., & Troje, N. (1997). Separation of texture and shape in images of faces for image coding and synthesis. Journal of the Optical Society of America A, 14, 2152-2161. 

     Wasserman, E. A. (1991). The pecking pigeon: A model of complex visual processing. Contemporary Psychology, 36, 605-606. 

     Wasserman, E. A. (1995). The conceptual abilities of pigeons. American Scientist, 83, 246-255. 

     Wasserman, E. A., & Astley, S. L. (1994). A behavioral analysis of concepts: its application to pigeons and children. In Douglas L. Medin (Ed.), The psychology of learning and motivation, advances in research and theory: Vol. 31. (pp. 73-132). San Diego, CA: Academic Press. 

     Wasserman, E. A., Kiedinger, R. E., & Bhatt, R. S. (1988). Conceptual behavior in pigeons: Categories, subcategories, and pseudocategories. Journal of Experimental Psychology: Animal Behavior Processes, 14, 235-246. 

     Watanabe, S. (1988). Failure of visual prototype learning in the pigeon. Animal Learning & Behavior, 16, 147-152.

Watanabe, S. (1991). Effects of ectostriatal lesions on natural concept, pseudoconcept, and artificial pattern discrimination in pigeons. Visual Neuroscience 6,  497-506. 

     Watanabe, S. (1993). Object-picture equivalence in the pigeon: An analysis with natural concept and pseudoconcept discriminations. Behavioural Processes, 30, 225-232. 

     Watanabe, S., Lea, S. E. G., & Dittrich, W. H. (1993). What can we learn from experiments on pigeon concept discrimination? In H. P. Zeigler & H.J. Bischof (Eds.), Vision, brain, and behavior in birds (pp. 351-376). Cambridge, MA: MIT Press. 

     Watanabe, S., Sakamoto, J., & Wakita, M. (1995). Pigeons' discrimination of paintings by Monet and Picasso. Journal of the Experimental Analysis of Behavior, 63, 165-174. 

     White, K. G., Alsop, B., & Williams, L. (1993). Prototype identification and categorization of incomplete figures by pigeons. Behavioural Processes, 30, 253-258. 

     Wilkie, D. M., Willson, R. J., & Kardal, S. (1989). Pigeons discriminate pictures of a geographic location. Animal Learning & Behavior, 17, 163-171. 

     Wittgenstein, L. (1953). Philosophical investigations. New York, NY: Macmillan. 

     Wright, A. A., Cook, R. C., Rivera, J. J., Sands, S. F., & Delius, J. D. (1988). Concept learning by pigeons: Matching-to-sample with trial-unique video picture stimuli. Animal Learning & Behavior, 16, 436-444.
 
 
    Acknowledgement
The work presented in this chapter was supported by grants from the Austrian Science Foundation (FWF P-7653-BIO and P-10975-BIO). 

I am indebted to Rupert Riedl, my teacher and mentor during the duration of the research. Thanks are due to Niko Troje for cooperation in the work presented in Section V of this chapter. A number of collaborators contributed countless hours (in alphabetical order): U. Aust, M. Fieder, M. Gottfried, D. Grass, R. Lenz, M. Loidolt, G. Michelbach, R. Nowotny, S. Ölzant, M. Pollirer, W. Weber. I am grateful to Fiona Campbell for improvement of the English of the manuscript.

Correspondence concerning this article should be sent to: Ludwig Huber, Institute of Zoology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria, Europe.  Electronic mail should be sent to:  ludwig.huber@univie.ac.at. You may also wish to visit our pigeon lab at the Institute of Zoology in Vienna.