Pattern detection in the presence of maskers that differ in spatial phase and temporal offset: threshold measurements and a model
Pattern detection in the presence of maskers that differ in spatial phase and temporal offset: threshold measurements and a model
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DOI：
10.1016/s0042-6989(99)00104-2
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发表时间：
1999-11-01
期刊：
影响因子：
1.8
通讯作者：
Chen, CC
中科院分区：
文献类型：
--
作者：
Foley, JM;Chen, CC
四个实验中，简短的伽柏图案被检测到的全场光栅或伽柏图案的存在下，在空间上叠加，但在空间相位和时间偏移（SOA）的变化。e1.阈值与掩蔽对比度（TvC）的功能，确定为相对相位为0，90，180和270度，SOA = 0。对于0度相对相位，随着对比度的增加，TvC功能降低（易化），然后增加（掩蔽）。对于90度，有很少或没有促进和阈值增加与掩蔽对比度。对于180度，TvC函数的形式随观察者和条件而变化。E2：与E1相似，不同之处在于掩蔽是Gabor模式。TvC函数在形式上类似于全场掩蔽器的函数，但掩蔽较少。E3：前掩蔽。在SOA =-33 ms时，确定了相对相位为0、90和180度的TvC函数。相对于SOA = 0时的TvC函数，0和180度的TvC函数的形式相反。E4：在0.063的恒定掩蔽对比度下，确定SOA为-100、-67、-33、0和33 ms时的TvP（阈值与相位）函数。掩蔽发生在所有相对阶段。对于同时和后向掩蔽，阈值对于0的相对相位是最小的，并且在180度处是最大的。对于前向掩蔽，函数的形式被反转。模式掩蔽和促进的模型（Foley，J. M.（1994 a）Journal of the Optical Society of America A，11，1710 - 1719）被扩展以考虑掩蔽相位和SOA效应。该模型假设四个机制调整到相位90度，并分别抑制所有相位的刺激。性能取决于观察者的检测策略。(C)1999爱思唯尔科技有限公司。保留所有权利。
Four experiments are described in which brief Gabor patterns are detected in the presence of full-field gratings or Gabor patterns that are superimposed in space, but vary in spatial phase and temporal offset (SOA). E1. Threshold versus masker contrast (TvC) functions were determined for relative phases of 0, 90, 180 and 270 degrees at SOA = 0. For 0 degrees relative phase, TvC functions decrease (facilitation) and then increase (masking) as contrast increases. For 90 degrees, there is little or no facilitation and thresholds increase with masker contrast. For 180 degrees, the form of the TvC function varies with observer and conditions. E2: Like E1, except that maskers are Gabor patterns. TvC functions are similar in form to those for full-field maskers, but there is less masking. E3: Forward masking. TvC functions were determined for relative phases of 0, 90, and 180 degrees at SOA = -33 ms. The forms of the TvC functions for 0 and 180 degrees are reversed relative to those at SOA = 0. E4: TvP (threshold versus phase) functions were determined for SOA's of -100, -67, -33, 0 and 33 ms at a constant masker contrast of 0.063. Masking occurs at all relative phases. For simultaneous and backward masking, the threshold is minimum for a relative phase of 0 and maximum at 180 degrees. For forward masking, the form of the function is inverted. A model of pattern masking and facilitation (Foley, J. M. (1994a) Journal of the Optical Society of America A, 11, 1710-1719) is extended to account for masker phase and SOA effects. The model assumes four mechanisms tuned to phases 90 degrees apart, and divisively inhibited by stimuli of all phases. Performance depends on the detection strategy of the observer. (C) 1999 Elsevier Science Ltd. All rights reserved.