Measuring the Soul

Carlo Aleci

Description

Even in the age of Internet, when information and knowledge are just a click away, few probably know what is psychophysics and what is it for.

Psychophysics can be romantically defined as the science that measures the soul, namely the sensory soul. Psychophysics estimates the sensibility and looks for the threshold, that ephemeral limit between the sensed and the not sensed, the perceived and the not perceived, the seen and the not seen. It is a challenging task, since this limit is like a butterfly twirling over a flowery meadow, and psychophysics is the tool aimed at measuring as exactly as possible the height of its flight.

At the boundary between experimental psychology and sensory neuroscience, psychophysics is not confined within a theoretical framework, but has great importance also in the clinical setting: audiologists, ophthalmologists, optometrists, orthoptists as well as neuropsychiatrists make use of psychophysics in many of their diagnostic protocols.

This book aims at describing the principles of this discipline in a simple yet rigorous form, so as to make psychophysics understandable to the broad audience of non-psychophysicists. And, why not, even to reveal its hidden charm...

Sujets

• Médecine
• Spécialités médicales
• Sciences de la nature
• Biologie
• Medical
• Ophthalmology
• Psychanalyse
• Psychologie

Informations

• Publié par: EDP Sciences
• Date de parution: 08 mars 2021
• Nombre de lectures: 0
• EAN13: 9782759825189
• Langue: English
• Poids de l'ouvrage: 7 Mo

Extrait

Current Natural Sciences

Carlo ALECI

P S Y C H O P H Y S I C S

Measuring the Soul Psychophysics for NonPsychophysicists

P S Y C H O P H Y S I C S

ISBN : 978-2-7598-2517-2

9 782759 825172

Current Natural Sciences

Measuring the Soul Psychophysics for NonPsychophysicists

Carlo ALECI

Even in the age of Internet, when information and knowledge are just a click away, few probably know what is psychophysics and what is it for.

Psychophysics can be romantically defined as the science that measures the soul, namely the sensory Psychophysics soul. estimates the sensibility and looks for the threshold, that ephemeral limit between the sensed and the not sensed , the perceived and the not perceived , the seen the and not seen . It is a challenging task, since this limit is like a butterfly twirling over a flowery meadow, and psychophysics is the tool aimed at measuring as exactly as possible the height of its flight.

At the boundary between experimental psychology and sensory neuroscience, psychophysics is not confined within a theoretical framework, but has great importance also in the clinical setting: audiologists, ophthalmologists, optometrists, orthoptists as well as neuropsychiatrists make use of psychophysics in many of their diagnostic protocols.

This book aims at describing the principles of this discipline in a simple yet rigorous form, so as to make psychophysics understandable to the broad audience of non-psychophysicists. And, why not, even to reveal its hidden charm...

Carlo ALECIwas born in 1969 in Turin. After specializing in Ophthalmology in 1997, Carlo obtained his Ph.D. degree in Ophthalmological Sciences at the University of Turin, where he is professor on contract of Strabology and Psychophysics of Vision since 2014. Ex-consultant at the Neuro-Ophthalmological Center of the University, his fields of interest are neuro-ophthalmology, visual psychophysics, and dyslexia. Author of several international papers and of the book “Dyslexia: A Visual Approach”, Carlo has developed tests aimed at evaluating the visuoperceptive alterations in the neuro- ophthalmological field. He is Editor-in-Chief of Neuro-Ophthalmology & Visual Neuroscience.

www.edpsciences.org

Current Natural Science

Carlo ALECI

Measuring the Soul

Psychophysics for NonPsychophysicists

Printed in France

EDP Sciences–ISBN(print): 9782759825172–ISBN(ebook): 9782759825189 DOI: 10.1051/9782759825172

All rights relative to translation, adaptation and reproduction by any means whatsoever are reserved, worldwide. In accordance with the terms of paragraphs 2 and 3 of Article 41 of the French Act dated March 11, 1957,“copies or reproductions reserved strictly for private use and not intended for collective use”and, on the other hand, analyses and short quotations for example or illustrative purposes, are allowed. Otherwise,“any representation or reproduction–whether in full or in part–without the consent of the author or of his successors or assigns, is unlawful”(Article 40, paragraph 1). Any representation or reproduction, by any means whatsoever, will therefore be deemed an infringement of copyright punishable under Articles 425 and following of the French Penal Code.

Science Press, EDP Sciences, 2021

To the Midnight Researchers. To those who dream of jumping beyond the fence. To my little Princess Sofia and my young Pirate Mattia.

Contents

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 1 Adequate and Inadequate Stimuli . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 2 The Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 Absolute and Difference Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Weber’s, Fechner’s and Stevens’Laws . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 3 The Psychometric Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 4 Detection and Discrimination Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 5 Response Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Yes/no Response Model [Y/N] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Alternative Forced Choice Model [AFC] . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 The“Implicit”AFC Version . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Target Probability in Y/N and AFC Response Models . . . . . . . . . . . . 5.4 Alternative Unforced Choice Response Model (AUC: Kaernbach, 2001) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 Modified AUC (Klein, 2001) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 6 FalseNegative and FalsePositive Errors (Lapse and Guess Rate) . . . . . . . . .

IX XI

1

3 4 5

9

17

21 21 21 24 27

28 29

31

VI

Contents

CHAPTER 7 Psychophysical Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 Nonadaptive Psychophysical Procedures: The Method of Constant Stimuli . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2 Nonadaptive Psychophysical Procedures: The Method of Limits and of the Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 8 Adaptive Psychophysical Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 9 Nonparametric Adaptive Psychophysical Procedures . . . . . . . . . . . . . . . . . . . 9.1 Truncated Staircase Method (Simple Updown Method: Dixon and Mood, 1948; von Békésy, 1960; Cornsweet, 1962) . . . . . . . . . . . . . 9.1.1 Two Interleaved Staircases to Preserve the Assumption of Independence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 Transformed Updown Staircase Method (Updown Transformed Response, UDTR: Wetherill and Levitt, 1965; Levitt, 1970) . . . . . . . . 9.2.1 (UDTR) Staircase with Rating of Confidence . . . . . . . . . . . . . . 9.3 ForcedChoice Tracking (Zwislockiet al., 1958) . . . . . . . . . . . . . . . . . . 9.4 Nonparametric Updown Staircase Method (Derman, 1957) . . . . . . . . 9.5 Weighted Updown Method (Kaernbach, 1991) . . . . . . . . . . . . . . . . . . 9.6 Stochastic Approximation (Robbins and Monro, 1951) . . . . . . . . . . . . 9.7 Accelerated Stochastic Approximation (Kesten, 1958) . . . . . . . . . . . . . 9.8 Block Updown Temporal Interval Forced Choice (BUDTIF: Campbell and Lasky, 1968) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.9 Parameter Estimation by Sequential Testing (PEST: Taylor and Creelman, 1967) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.10 A More Virulent PEST (Findlay, 1978) . . . . . . . . . . . . . . . . . . . . . . . . 9.11 Binary Search and Modified Binary Search (MOBS: Tyrrell and Owens, 1988) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 10 Parametric Adaptive Psychophysical Procedures . . . . . . . . . . . . . . . . . . . . . . 10.1 The Maximum Likelihood Estimation [MLE] . . . . . . . . . . . . . . . . . . . 10.1.1 Psychophysical Procedures Based on MLE: The Best PEST (Pentland, 1980; Lieberman and Pentland, 1982) . . . . . . . . . 10.1.2 The MLE Simplified Approximation of Emerson (Emerson, 1984) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.2 Bayesian Psychophysical Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 10.2.1 Quick Estimation by Sequential Testing (QUEST: Watson and Pelli, 1979, 1983) . . . . . . . . . . . . . . . . . . . . . . . 10.2.2 ZEST (Zippy Estimation of Sequential Testing: KingSmithet al., 1994) . . . . . . . . . . . . . . . . . . . . . . . . . . . .

35

35

38

41

45

45

48

48 49 50 50 51 53 55

57

57 61

62

69 70

75

75 76

79

80

Contents

10.2.3

10.2.4

10.2.5

10.2.6 10.2.7

The Minimum Variance Method (KingSmith, 1984; KingSmithet al., 1994) . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Ideal Procedure: Behemothic Estimation of Sequential Testing (BEST: Pelli, 1987; Sims and Pelli, 1987) . . . . . . . . . YAAP (“Yet Another Adaptive Procedure: Treutwein, 1997”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Step Method (Simpson, 1989) . . . . . . . . . . . . . . . . . . . . MUEST (Snoeren and Puts, 1997) . . . . . . . . . . . . . . . . . . . .

CHAPTER 11 Adaptive Psychophysical Procedures for the Estimate of the Slope . . . . . . . . 11.1 Adaptive Probit Estimation (APE: Watt and Andrews, 1981) . . . . . . 11.2 Hall’s Hybrid Procedure (Hall, 1981) . . . . . . . . . . . . . . . . . . . . . . . . . 11.3 The Simulated Staircase Technique of Leek, Hanna and Marshall (Leeket al., 1992) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.4 The Adaptive Threshold and Slope Estimation (ATASE: Kaernbach, 2001b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.5 Modified ZEST (KingSmith and Rose, 1997) . . . . . . . . . . . . . . . . . . 11.6 TheΨMethod (Kontsevich and Tyler, 1999) . . . . . . . . . . . . . . . . . . 11.7 The Sweet PointBased MLE Procedure of Shen and Richards (2012) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 12 Multidimensional Adaptive Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 The Functional Adaptive Sequential Testing (FAST: Vulet al., 2010) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 The Quick CSF Method (qCSF: Lesmeset al., 2010) . . . . . . . . . . . . . 12.3 The Quick TvC Method (Lesmeset al., 2006) . . . . . . . . . . . . . . . . . . 12.4 The MEEE Method of CoboLewis for Performance Categorization . . .

CHAPTER 13 What Makes a Psychophysical Technique a Good Psychophysical Technique? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1 Assessing the Stability of the Psychometric Function . . . . . . . . . . . . . 13.1.1 The Method of Hall (1983) . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1.2 The Interleaved Tracking Procedure of Leeket al. (1991) . . . 13.2 Assessing the Goodnessoffit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 14 What is the Best Psychophysical Technique? . . . . . . . . . . . . . . . . . . . . . . . . 14.1 AFC or Y/N: Which is the Best Response Model? . . . . . . . . . . . . . . 14.1.1 Subjective Criterion in the Y/N and Bias in nAFC Response Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.1.2 Drawbacks of thenAFC Response Models . . . . . . . . . . . . . .

VII

81

82

83 84 86

87 92 94

94

95 99 104

107

113

114 118 120 123

127 130 131 133 134

137 137

137 139

VIII

14.2

14.3 14.4

Contents

14.1.3 Drawbacks of the Y/N Response Model . . . . . . . . . . . . . . . . 14.1.4 Spatial or Temporal AFC? How Many Forced Choices? . . . . What is the Best Psychophysical Procedure? . . . . . . . . . . . . . . . . . . . 14.2.1 Nonadaptivevs. Adaptive Procedures . . . . . . . . . . . . . . . . . . 14.2.2 Adaptive Nonparametric Procedures: Variablevs. Fixed Step Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.2.3 Adaptive Nonparametricvs. Parametric Procedures . . . . . . . 14.2.4 Adaptive Parametric Procedures . . . . . . . . . . . . . . . . . . . . . 14.2.5 Considerations on the Staircase Procedures with Fixed Step Size: the Optimal Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drawbacks of the Maximum Likelihood Estimation . . . . . . . . . . . . . . Drawback of the Bayesian Procedures . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 15 Introduction to the Signal Detection Theory . . . . . . . . . . . . . . . . . . . . . . . . . 15.1 SDT and the ROC Curve in Y/N and 2AFC Response Models . . . . . 15.2 The SingleInterval Adjustment Matrix Procedure (SIAM: Kaernbach, 1990) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 16 Suprathreshold Psychophysics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16.1 Procedures Based on Magnitude Scaling: Category Scaling . . . . . . . . 16.2 Procedures Based on Magnitude Estimation . . . . . . . . . . . . . . . . . . . 16.3 Procedures Based on Reaction Time . . . . . . . . . . . . . . . . . . . . . . . . .

CHAPTER 17 Brief Outline of Comparative Psychophysics . . . . . . . . . . . . . . . . . . . . . . . . .

Afterword. The Inverse Problem of Perception . . . . . . . . . . . . . . . . . . . . .

Appendix I Logistic and Weibull Distribution . . . . . . . . . . . . . . . . . . . . . . Appendix II The Maximum Likelihood Estimation . . . . . . . . . . . . . . . . . . Appendix III Probit Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . Appendix IV About Bayes’Theorem and Bayesian Statistics . . . . . . . . .

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . .

141 142 144 144

145 146 147

148 150 153

155 161

164

169 169 170 171

173

175

179 181 185 189

195

201