Presentation is loading. Please wait.

Presentation is loading. Please wait.

Beauty in the Eye of the Beholder The Relativity of Visual Experience Andrew Duggins Westmead Hospital, University of Sydney

Similar presentations


Presentation on theme: "Beauty in the Eye of the Beholder The Relativity of Visual Experience Andrew Duggins Westmead Hospital, University of Sydney"— Presentation transcript:

1

2 Beauty in the Eye of the Beholder The Relativity of Visual Experience Andrew Duggins Westmead Hospital, University of Sydney

3 Is Experience Relative? Do the transformations of Einstein’s special relativity apply to subjective spacetime? Just as… – gravity is the curvature of objective spacetime by mass – attention is the curvature of subjective spacetime by information

4 Plan Subjective spacetime Special relativity – Time dilation – Limiting speed c Information theory – Efficient encoding General Relativity – Oddball effects – Artist’s perspective – Equivalence principle – Visual inattention – Sketch of a unifying theory

5 XII VI IX III IIX IV III XI

6 XII VI IX III

7

8 1 1 t x

9 1 1 t x

10 1 1 t x

11 1 1 t x

12 1 1 t x

13 1 1 t x

14 1 1 t x

15 1 1 t x

16 1 1 t x

17 1 1 t x t

18 1 1 t x t Speed of light, c = 1

19 1 1 t x t c ≠ 1

20 1 1 t x t

21 1 1 t x t x 1 1

22 t x 1 1 t x 1 1 t 2 – x 2 = 1

23 1 1 t x t 1

24 t x 1 1 t x 1 1 t 2 – x 2 = t 2 = 1 t2t2 – x 2 = 1 τ = 1 Proper time, τ = √ (t 2 – x 2 )

25 XII VI IX III IIX IV III XI

26 XII VI IX III IIX IV III XI

27 t x 1 1 t x 1 1 t x 1 1

28 speed, v 1 rapidity, φ Speed of light, c = v = tanh φ

29 Vestibulo-ocular reflex

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

101

102 Vestibular nystagmus

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283 Pulaski et al, Brain Research, 1981

284 c = 500 deg/sec v eye /500 = tanh (v head /500) Pulaski et al, Brain Research, 1981

285 Is Experience Relative? Do the transformations of Einstein’s special relativity apply to subjective spacetime? …..Perhaps!

286  00  01  10  11 To encode the sequence: 2 binary digits per trial

287 ¼ ½ Probability (P) Information (I) = -log 2 (P) I 1 bit 2 bits 3 bits P½¼1/81/8P½¼1/81/8

288

289  0  10  110  111 To encode the sequence: 1.75 binary digits per trial 1.75 bits = = ‘Entropy’ 1.75 bits/trial = the most efficient possible code P = ½ P = ¼ P = 1 / 8

290 Choice Reaction Time Task

291 Choice Reaction Time Hick, 1952 – k items – Reaction time  log 2 (k) Hyman, 1953 – Skewed distributions – Reaction time  Entropy – ~ 129ms/bit Our Hypothesis Quicker reactions for more probable alternatives Minimum reaction time on average

292

293 ‘Efficient Coding’ Hypothesis Survival depends on the minimum average reaction time Reaction time to stimulus x depends on the length of the ‘neural codeword’ Codeword length, and visual processing activity should vary with self-information, - log 2 P(x)

294

295 Strange et al (2005)

296 Comments Attention – Coextensive with visual attention network – ‘Oddball’ responses reflect efficient coding Repetition suppression – Updated probabilities increase with repetition – Self-information incrementally decays The Neural Codeword

297 Subjective Duration 1 Pariyadath, Eagleman (2007) 2 nd object: P = 1/2 P = 1/6 1 bit 2.58 bits Random 2 nd object perceived to last 60ms > Repeated = an extra 38ms/bit

298 Subjective Duration 2 Pariyadath, Eagleman (2007) Random/Sequential 2 nd object: ‐log 2 (1/3) = 1.58 bits Scrambled 2 nd object: ‐log 2 (1/9) = 3.17 bits Relative delay 75ms=an extra 47ms/bit

299 Coding Hypothesis Stimulus information expands: – Subjective duration – Reaction latency …to a similar extent

300 Am I a blue circle? Zombie celebrity heads

301 Conclusions Information prolongs experience Information delays reaction – Efficient coding – Minimum expected reaction time Experience first, react later: Information quantifies the difficulty inherent in the ‘Hard’ problem

302 Duration Dilation by Information Objective time 320ms 1 Bit 360ms Subjective time 2 Bits Subjective time 400ms 0 Bits 40ms / bit

303

304 Hypothesis Gravity is the curvature of objective spacetime by mass Attention is the curvature of subjective spacetime by information Time Space

305

306

307

308

309

310 r 2 =x2x2 + y 2

311 θ dr 2 + r 2 dθ 2 dσ 2 ≠ Length dilation at distance: dσ/dr = 1/√(1 + r 2 ) << 1

312

313 Equivalence Principle

314

315 Left Visual Inattention

316 Left Vestibular Stimulation

317 Left Angular Acceleration

318 Visual Inattention 0 π/6 π/3 π/2 2π/3 5π/6 π x = θ 1 metre

319

320

321 0π/6π/3π/22π/35π/6π x σ dσ/dx > 1

322 0π/6π/3π/22π/35π/6π x σ dσ/dx ≈ 1 Length contraction as x → 0

323 0π/6π/3π/22π/35π/6π x σ dτ/dt < 1 Basso et al, Neuroreport, 1996

324 0π/6π/3π/22π/35π/6π x s dτ/dt ≈ 1 Time dilation as x → 0

325 dτ 2 = (1 – 2MG/x) dt 2 – 1/(1 – 2MG/x) dx 2 -MG/x = ‘gravitational potential’ dτ 2 = (1 – 2IA/x) dt 2 – 1/(1 – 2IA/x) dx 2 -IA/x = ‘attentional potential’ I = ‘reduction in uncertainty’A = ‘attentional constant’


Download ppt "Beauty in the Eye of the Beholder The Relativity of Visual Experience Andrew Duggins Westmead Hospital, University of Sydney"

Similar presentations


Ads by Google