Dr William Simpson
Profiles

Dr William Simpson

Associate Professor (Reader)

School of Psychology (Faculty of Health and Human Sciences)

Qualifications

PhD Psychology University of Toronto

Research interests

My lab studies how human vision works, using direct measurements of brain activity (fNIRS) and psychophysics. Research topics include pattern perception, motion perception, visual reaction time, ideal observer models, perceptual development, and individual differences in vision.

Research page

Grants & contracts

2005-2010 Natural Sciences and Engineering Research Council (Canada) Research Grant. Noise in the visual system. $100,000 total.

2002 Engineering and Physical Sciences Research Council (UK) Research Grant. European Conference on Visual Perception. Co-investigator, with P. Mamassian, F. Pollick, & D. Simmons. £16,711 total.

2001-2003 EPSRC Research Grant . Efficiency of human suprathreshold visual detection. £56,135 total.

2000-2002 Biotechnology and Biological Sciences Research Council (UK) Research Grant. Dynamics of visual processing of first- and second-order spatial information. Co-investigator, with V. Manahilov. £106,100 total.

Key publications are highlighted

Journals
Articles
Falkenberg HK, Simpson WA & Dutton GN 2014 'Development of sampling efficiency and internal noise in motion detection and discrimination in school-aged children' Vision Res 100, 8-17 Author Site , DOI
Simpson WA, Loffler G & Tucha L 2013 'Cross-correlation in face discrimination' Vision Res 76, 60-67 Author Site , DOI
Wijeakumar S, Shahani U, Simpson WA & McCulloch DL 2013 'Haemodynamic responses to radial motion in the visual cortex' JOURNAL OF NEAR INFRARED SPECTROSCOPY 21, (4) 231-236 Author Site , DOI
Wijeakumar S, Shahani U, Simpson WA & McCulloch DL 2012 'Localization of hemodynamic responses to simple visual stimulation: an fNIRS study' Invest Ophthalmol Vis Sci 53, (4) 2266-2273 Author Site , DOI
Wijeakumar S, Shahani U, McCulloch DL & Simpson WA 2012 'Neural and vascular responses to fused binocular stimuli: a VEP and fNIRS study' Invest Ophthalmol Vis Sci 53, (9) 5881-5889 Author Site , DOI
Tucha L & Simpson WA 2011 'The role of time on task performance in modifying the effects of gum chewing on attention' Appetite 56, 299-301
Northway N, Manahilov V & Simpson WA 2010 'Coloured filters improve exclusion of perceptual noise in visually symptomatic dyslexics' Journal of Research in Reading 33, 223-230
Tucha L, Simpson WA, Evans L, Birrel L, Sontag TA, Lange KW & Tucha O 2010 'Detrimental effects of gum chewing on vigilance in children with attention deficit hyperactivity disorder' Appetite 55, 679-684
Aydin S, Manahilov V, Shahani U, Strang NC & Simpson WA 2009 'Age-related changes in perceptual rivalry' PERCEPTION 38, 148-148 Author Site
Simpson WA, Manahilov V & Shahani U 2009 'Two eyes: sqrt(2) better than one?' Acta Psychologica 131, 93-98
Mihaylov P, Manahilov V, Simpson WA & Strang NC 2007 'Induced internal noise in perceptual artificial scotomas created by surrounding dynamic noise' Vision Research 47, (11) 1479-1489
Gordon GE, Manahilov V, Dutton G, Shahani U & Simpson W 2007 'Seeing the bigger picture: Evidence for altered global motion processing in migraine' Perception 36, 140-140
Manahilov V, Gordon G, Calvert J & Simpson WA 2007 'Subtractive suppression underlies contrast processing of visual stimuli' Perception 36, (2) 307-307
Manahilov V, Shahani U & Simpson WA 2006 'Perceptive fields for detecting global orientation and motion direction in normal and amblyopic observers' Perception 35, (3) 418-418
Simpson WA & Manahilov V 2006 'The two-pulse experiment and cross-correlation' Vision Research 46, (8-9) 1178-1179
Mihaylov P, Manahilov V, Strang N & Simpson WA 2006 'Time course of induced neural activity over long distances in the human visual cortex' Perception 35, 15-16
Calvert J, Manahilov V, Simpson WA & Parker DM 2005 'Human cortical responses to contrast modulations of visual noise' Vision Research 45, (17) 2218-2230
Simpson WA, Shahani U & Manahilov V 2005 'Illusory percepts of moving patterns due to discrete temporal sampling' Neuroscience Letters 375, (1) 23-27
Simpson WA, Shahani U & Manahilov V 2005 'Illusory percepts of moving patterns due to discrete temporal sampling' NEUROSCIENCE LETTERS 375, (1) 23-27 Author Site , DOI
Simpson WA & McFadden SM 2005 'Spatial frequency channels derived from individual differences' Vision Research 45, (21) 2723-2727
Andrews TJ, Purves D, Simpson WA & VanRullen R 2005 'The wagonwheel illusion: Reply to Holcombe et al. Trends in Cognitive Sciences' Trends in Cognitive Sciences 9, 560-561
Andrews TJ, Purves D, Simpson WA & VanRullen R 2005 'The wheels keep turning' Trends in Cognitive Sciences 9, (12) 560-561
Manahilov V, Simpson WA & Calvert J 2005 'Why is second-order vision less efficient than first-order vision?' Vision Research 45, (21) 2759-2772
Manahilov V, Findlay K & Simpson WA 2004 'Factors limiting suprathreshold vision measured by a flash-sound simultaneity paradigm' Vision Research 44, (22) 2577-2585
Manahilov V, Findlay K & Simpson WA 2004 'Factors limiting suprathreshold vision measured by a flash-sound simultaneity paradigm' VISION RESEARCH 44, (22) 2577-2585 Author Site , DOI
Simpson WA, Findlay K & Manahilov V 2003 'Efficiency and internal noise for detection of suprathreshold patterns measured using simple reaction time' Vision Research 43, (10) 1103-1109
Braun WJ, Rousson V, Simpson WA & Prokop J 2003 'Parametric modeling of reaction time experiment data' Biometrics 59, (3) 661-669
Simpson WA, Falkenberg HK & Manahilov V 2003 'Sampling efficiency and internal noise for motion detection, discrimination, and summation' Vision Research 43, (20) 2125-2132
Manahilov V, Calvert J & Simpson WA 2003 'Temporal properties of the visual responses to luminance and contrast modulated noise' Vision Research 43, (17) 1855-1867
Manahilov V, Simpson WA & Calvert J 2002 'Ability to use phase information in discrimination of second-order patterns' Perception 31, 46-46
Calvert J, Manahilov V & Simpson WA 2002 'Are different cortical generators involved in the processing of first-order and second-order patterns?' Perception 31, 32-32
Falkenberg HK, Simpson WA & Manahilov V 2002 'Development of sampling efficiency and internal noise in motion detection and discrimination' Investigative Ophthalmology & Visual Science 43, U1335-U1335
Northway N, Manahilov V & Simpson WA 2002 'Dyslexics show poor efficiency in detection and discrimination visual tasks' Perception 31, 165-166
Simpson WA, Findlay K & Manahilov V 2002 'Limitations to visual detection of suprathreshold patterns' Perception 31, 90-90
Gordon GE, Manahilov V, Calvert J & Simpson WA 2002 'The manipulation of orientation and spatial-frequency components of noise gives rise to opposing effects on the visual evoked response' Perception 31, 33-33
Manahilov V & Simpson WA 2001 'Energy model for contrast detection: spatial-frequency and orientation selectivity in grating summation' Vision Research 41, (12) 1547-1560
Simpson WA & Manahilov V 2001 'Matched filtering in motion detection and discrimination' Proceedings of the Royal Society of London Series B-Biological Sciences 268, (1468) 703-709
Manahilov V, Simpson WA & McCulloch DL 2001 'Spatial summation of peripheral Gabor patches' Journal of the Optical Society of America A-Optics Image Science and Vision 18, (2) 273-282
Manahilov V, Calvert J & Simpson WA 2001 'Temporal summation of luminance and contrast modulated visual noise' Investigative Ophthalmology & Visual Science 42, (4) S160-S160
Findlay K, Simpson WA & Simmons D 2000 'Are briefly presented letter-like shapes perceived categorically?' PERCEPTION 29, 22-22
Findlay K, Simpson WA & Simmons D 2000 'Are briefly presented letter-like shapes perceived categorically?' PERCEPTION 29, 22-22 Author Site
Manahilov V, Simpson WA & McCulloch DL 2000 'Detection efficiency of peripheral Gabor patches' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 41, (4) S714-S714 Author Site
Simpson WA, Braun WJ, Bargen C & Newman AJ 2000 'Identification of the eye–brain–hand system with point processes: A new approach to simple reaction time' Journal of Experimental Psychology: Human Perception and Performance 26, (6) 1675-1690 , DOI
Simpson WA, Manahilov V & Mair MS 2000 'Is motion processing unitary? (vol 16, pg 2836, 1999)' JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION 17, (6) 1134-1134 Author Site , DOI
Simpson WA, Manahilov V & Mair MS 1999 'Is motion processing unitary?' J Opt Soc Am A Opt Image Sci Vis 16, (12) 2836-2844 Author Site
Simpson WA & Newman A 1998 'Motion detection and directional tuning' Vision Res 38, (11) 1593-1604 Author Site
Simpson WA, Newman A & Aasland W 1997 'Equivalent background speed in recovery from motion adaptation' J Opt Soc Am A Opt Image Sci Vis 14, (1) 13-22 Author Site
Simpson WA & Newman A 1997 'Motion detection and directional tuning' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 38, (4) 1780-1780 Author Site
Giaschi DE, Simpson WA, Ferdinandi AK & Tata MS 1997 'The effect of stationary noise on global motion perception' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 38, (4) 358-358 Author Site
Simpson WA, Newman A & Aasland W 1996 'Equivalent background speed in recovery from motion adaptation' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 37, (3) 3433-3433 Author Site
Simpson WA & Finsten BA 1995 'Pedestal effect in visual motion discrimination' J Opt Soc Am A Opt Image Sci Vis 12, (12) 2555-2563 Author Site
SIMPSON WA & AASLAND W 1995 'TEMPORAL SUMMATION OF IMAGE EXPANSION/CONTRACTION, ROTATION, AND TRANSLATION' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 36, (4) S830-S830 Author Site
Simpson WA 1994 'Temporal summation of visual motion' Vision Res 34, (19) 2547-2559 Author Site
SIMPSON WA 1994 'TEMPORAL SUMMATION OF VISUAL-MOTION' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 35, (4) 1273-1273 Author Site
Simpson WA 1993 'Optic flow and depth perception' Spat Vis 7, (1) 35-75 Author Site
Simpson WA & Swanston MT 1991 'Depth-coded motion signals in plaid perception and optokinetic nystagmus' Exp Brain Res 86, (2) 447-450 Author Site
SIMPSON WA 1991 'DETECTION OF ACCELERATION IN DEPTH' INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 32, (4) 957-957 Author Site
SWANSTON M & SIMPSON WA 1990 'PLAID PERCEPTION AND OPTOKINETIC NYSTAGMUS WITH DEPTH SEPARATION BETWEEN MOVING GRATINGS' PERCEPTION 19, (3) 341-341 Author Site
Swanston M & Simpson WA 1990 'Plaid perception and opto-kinetic nystagmus with depth separation between moving gratings' PERCEPTION 19, (4) 341-341 Author Site
Simpson WA 1990 'The use of different features by the matching process in short-range motion' Vision Res 30, (10) 1421-1428 Author Site
Howard IP & Simpson WA 1989 'Human optokinetic nystagmus is linked to the stereoscopic system' Experimental Brain Research 78, 309-314
TOPPER DR & SIMPSON WA 1981 'DEPTH-PERCEPTION IN LINEAR AND INVERSE PERSPECTIVE PICTURES' PERCEPTION 10, (3) 305-312 Author Site , DOI
Conference Papers
Carney T, Klein SA, Beutter B, Norcia AM, Chen C, Tyler CW, Makous W, Watson AB, Cropper SJ & Popple AV 2002 'Extending the Modelfest image/threshold database into the spatio-temporal domain' Rogowitz BE; Pappas TN 2002 SPIE, Human Vision and Electronic Imaging VII //0 //0 138-148