Perceiving affordances: visual guidance of stair climbing.

How do animals visually guide their activities in a cluttered environment? Gibson (1979) proposed that they perceive what environmental objects offer or afford for action. An analysis of affordances in terms of the dynamics of an animal-environment system is presented. Critical points, corresponding to phase transitions in behavior, and optimal points, corresponding to stable, preferred regions of minimum energy expenditure, emerge from variation in the animal-environment fit. It is hypothesized that these points are constants across physically similar systems and that they provide a natural basis for perceptual categories and preferences. In three experiments these hypotheses are examined for the activity of human stair climbing, by varying riser height with respect to leg length. The perceptual category boundary between "climbable" and "unclimbable" stairs is predicted by a biomechanical model, and visually preferred riser height is predicted from measurements of minimum energy expenditure during climbing. It is concluded that perception for the control of action reflects the underlying dynamics of the animal-environment system.

[1]  E. Buckingham.  On Physically Similar Systems; Illustrations of the Use of Dimensional Equations , 1914 .

[2]  F. G. Benedict,et al.  THE ENERGY METABOLISM OF WOMEN WHILE ASCENDING OR DESCENDING STAIRS , 1928 .

[3]  A. Hill.  The Heat Production in Isometric and Isotonic Twitches , 1930 .

[4]  E. Tolman.  Purposive behavior in animals and men , 1932 .

[5]  N. Lewis.  A dynamic theory of personality , 1935 .

[6]  K. Koffka.  Principles Of Gestalt Psychology , 1936 .

[7]  J. Krutch,et al.  The Measure of Man , 1953 .

[8]  L. B. Alberti,et al.  Ten books on architecture , 1956 .

[9]  J. Booyens,et al.  The expenditure of energy by men and women walking , 1957, The Journal of physiology.

[10]  J. Gibson.  Visually controlled locomotion and visual orientation in animals. , 1998, British journal of psychology.

[11]  Marjorie B. Keiser.  Relationship of posture to energy expenditure and other physiological responses of women ascending and descending stairways , 1959 .

[12]  W. R. Stahl.  Dimensional analysis in mathematical biology I. General discussion , 1961 .

[13]  N. Shinno.  [Dynamic analysis of the movement of the knee. 5. Analysis of knee function in ascending and descending stairs]. , 1961, Nihon Seikeigeka Gakkai zasshi.

[14]  W. R. Stahl.  Similarity Analysis of Physiological Systems , 2015, Perspectives in biology and medicine.

[15]  R J DRILLIS,et al.  Folk Norms and Biomechanics , 1963, Human factors.

[16]  J. Workman,et al.  Oxygen cost of treadmill walking. , 1963, Journal of applied physiology.

[17]  C. S. Holling.  The Analysis of Complex Population Processes , 1964, The Canadian Entomologist.

[18]  A. B. Drought,et al.  WALKING PATTERNS OF NORMAL MEN. , 1964, The Journal of bone and joint surgery. American volume.

[19]  G. A. Dean,et al.  AN ANALYSIS OF THE ENERGY EXPENDITURE IN LEVEL AND GRADE WALKING , 1965 .

[20]  H. Ralston,et al.  ENERGY COST OF STAIR‐CLIMBING IN NORMAL AND HEMIPLEGIC SUBJECTS , 1965, American journal of physical medicine.

[21]  M. Richardson.  Physiological responses and energy expenditures of women using stairs of three designs. , 1966, Journal of applied physiology.

[22]  Bruce Fm,et al.  Oxygen consumption and heart rate during stair climbing. , 1967 .

[23]  J. Joseph,et al.  Telemetering electromyography of muscles used in walking up and down stairs. , 1967, The Journal of bone and joint surgery. British volume.

[24]  Morrison Jb.  Function of the knee joint in various activities. , 1969 .

[25]  J. Weiner,et al.  Human biology: A guide to field methods; , 1969 .

[26]  J. B. Morrison.  Function of the knee joint in various activities. , 1969, Biomedical engineering.

[27]  J B Morrison,et al.  The mechanics of muscle function in locomotion. , 1970, Journal of biomechanics.

[28]  K. DuChatinier,et al.  Step length, step frequency and temporal factors of the stride in normal human walking. , 1970 .

[29]  Charles George Ramsey,et al.  Architectural Graphic Standards , 1970 .

[30]  E. Corlett,et al.  Ramps or stairs: the choice using physiological and biomechanic criteria. , 1972, Applied ergonomics.

[31]  R. F. Goldman,et al.  Terrain coefficients for energy cost prediction. , 1972, Journal of applied physiology.

[32]  H. Sedgwick.  The visible horizon: A potential source of visual information for the perception of size and distance. , 1973 .

[33]  M. Bunge.  On Confusing ‘Measure’ with ‘Measurement’ in the Methodology of Behavioral Science , 1973 .

[34]  T. McMahon,et al.  Scaling Stride Frequency and Gait to Animal Size: Mice to Horses , 1974, Science.

[35]  Tommaso Leo,et al.  Biomechanics of Walking Up Stairs , 1974 .

[36]  B. Gunther.  Dimensional analysis and theory of biological similarity , 1975 .

[37]  T. McMahon.  Using body size to understand the structural design of animals: quadrupedal locomotion. , 1975, Journal of applied physiology.

[38]  H. Ralston.  Energetics of Human Walking , 1976 .

[39]  K B Pandolf,et al.  Metabolic energy expenditure and terrain coefficients for walking on snow. , 1976, Ergonomics.

[40]  Graham H. Pyke,et al.  Optimal Foraging: A Selective Review of Theory and Tests , 1977, The Quarterly Review of Biology.

[41]  Dieterich J. Schuring,et al.  Scale models in engineering , 1977 .

[42]  A. Iberall.  A field and circuit thermodynamics for integrative physiology. I. Introduction to the general notions. , 1977, The American journal of physiology.

[43]  D. Ingle,et al.  The effect of viewing distance upon size preference of frogs for prey , 1977, Vision Research.

[44]  T. McMahon,et al.  Fast running tracks. , 1978, Scientific American.

[45]  R. Rosen.  Dynamical similarity and the theory of biological transformations. , 1978, Bulletin of mathematical biology.

[46]  Robert Rosen,et al.  Fundamentals Of Measurement And Representation Of Natural Systems , 1978 .

[47]  A. Iberall.  A field and circuit thermodynamics for integrative physiology. III. Keeping the books--a general experimental method. , 1978, The American journal of physiology.

[48]  V. Dietz,et al.  Pre-innervation and stretch responses of triceps bracchii in man falling with and without visual control , 1978, Brain Research.

[49]  J. Gibson.  The Ecological Approach to Visual Perception , 1979 .

[50]  J Panero,et al.  HUMAN DIMENSION AND INTERIOR SPACE: A SOURCEBOOK OF DESIGN REFERENCE STANDARDS , 1979 .

[51]  J. Cerella.  Visual classes and natural categories in the pigeon. , 1979, Journal of experimental psychology. Human perception and performance.

[52]  G. M. Branch,et al.  Aggression by limpets against invertebrate predators , 1979, Animal Behaviour.

[53]  P. N. Kugler,et al.  1 On the Concept of Coordinative Structures as Dissipative Structures: I. Theoretical Lines of Convergence* , 1980 .

[54]  D. Winter.  Biomechanics of Human Movement , 1980 .

[55]  D. F. Hoyt,et al.  Gait and the energetics of locomotion in horses , 1981, Nature.

[56]  M. Turvey,et al.  Ecological laws of perceiving and acting: In reply to Fodor and Pylyshyn (1981) , 1981, Cognition.

[57]  R. Shaw,et al.  Psychophysics and ecometrics , 1981, Behavioral and Brain Sciences.

[58]  David N. Lee,et al.  Plummeting gannets: a paradigm of ecological optics , 1981, Nature.

[59]  M. Ghiselin.  Categories, life, and thinking , 1981, Behavioral and Brain Sciences.

[60]  William Howe Warren,et al.  A BIODYNAMIC BASIS FOR PERCEPTION AND ACTION IN BIPEDAL CLIMBING , 1982 .

[61]  H. Wagner.  Flow-field variables trigger landing in flies , 1982, Nature.

[62]  David N. Lee,et al.  Visual Timing in Hitting An Accelerating Ball , 1983, The Quarterly journal of experimental psychology. A, Human experimental psychology.