
Figure 1
External inputs to response codes, response-code activations, and differences between response-code activations for Model A (upper row of graphs) and Model B (lower row of graphs). Continuous lines are for correct responses, dashed lines for error responses. The first vertical dotted line marks the end of the lead of the irrelevant input, the second vertical dotted line marks the end of the decision (reaching the threshold). Parameters were λ = .2, β = .2, σn = 0, Irel = .7, ΔIirr = –.2, δ = .1, d = –.1, θ = 1. The figures show an incongruent trial only.

Figure 2
Different shapes of delta plots generated with Models A and B, using the parameters listed in Table 1, showing decreasing (continuous lines), increasing (dashed lines), and delayed (dotted lines) congruency effects. For each congruent (positive ΔIirr) and incongruent condition (negative ΔIirr) 100,000 trials were simulated.
Table 1
Parameters used to generate the delta plots of Figure 2.
| MODEL A | MODEL B | |||||
|---|---|---|---|---|---|---|
| PARAMETER | DECREASING | INCREASING | DELAYED | DECREASING | INCREASING | DELAYED |
| λ | .25 | .25 | .25 | .25 | .25 | .25 |
| β | .20 | .20 | .20 | .20 | .20 | .20 |
| σn | .20 | .20 | .20 | .20 | .20 | .20 |
| Irel | .70 | .70 | .70 | 1.20 | .70 | .70 |
| ΔIirr | ±.15 | ±.15 | ±.15 | ±.15 | ±.15 | ±.15 |
| δ | .10 | .10 | .10 | .05 | .10 | .10 |
| μD | -.10 | 0 | .20 | -.30 | 0 | .20 |
| wD | .20 | .10 | .10 | .20 | .10 | .10 |
| θ | 1.00 | 1.00 | 1.00 | 1.30 | 1.00 | 1.00 |
| μR | .10 | .15 | .15 | .02 | .15 | .15 |
| wR | 0 | 0 | 0 | 0 | 0 | 0 |
Table 2
Parameter estimates for Model B (in brackets for model A). Congruent and incongruent conditions differed only in the algebraic sign of ΔIirr, positive values for congruent and negative values for incongruent conditions, respectively. For the data of Richter and Wühr (2022) the absolute value of ΔIirr could also vary across the three pairs of conditions with different size differences (sizes are italicized). Time parameters (δ, μD, wD, μR, and wR) are in seconds.
| PARAMETER | WÜHR & SEEGELKE | RICHTER & WÜHR |
|---|---|---|
| λ (self-inhibition gain) | 0.270 (0.269) | 0.269 (0.269) |
| β (lateral-inhibition gain) | 0.349 (0.345) | 0.306 (0.305) |
| σn (standard deviation of noise) | 0.282 (0.282) | 0.272 (0.265) |
| Irel (relevant input) | 0.708 (0.707) | 0.719 (0.719) |
| ΔIirr (irrelevant input) for sizes 20–40: | ± 0.064 (0.062) | |
| 10–60: | ± 0.127 (0.126) | |
| 20–50: | ± 0.141 (0.141) | |
| 30–40: | ± 0.042 (0.042) | |
| δ (time constant for irrelevant input) | 0.071 (0.069) | 0.031 (0.031) |
| μD (mean temporal offset) | 0.180 (0.172) | 0.208 (0.208) |
| wD (width of temporal-offset distribution) | 0.053 (0.052) | 0.093 (0.093) |
| θ (response threshold) | 1.068 (1.070) | 1.018 (1.018) |
| μR (mean residual time) | 0.180 (0.180) | 0.176 (0.176) |
| wR (width of residual-time distribution) | 0.059 (0.060) | 0.063 (0.063) |
| costs | 4.7 (4.7) | 6.0 (6.0) |
Table 3
Observed and predicted mean error percentages (EP) as well as means of the individual means (MRT) and standard deviations (SDRT) of reaction times of correct trials (in milliseconds). For the observed means the standard errors are added. Predicted values of Model A are in brackets.
| OBSERVED | PREDICTED | ||||
|---|---|---|---|---|---|
| STIMULUS SIZES (MM) | CONGRUENT | INCONGRUENT | CONGRUENT | INCONGRUENT | |
| 20–40 | EP (%) | 2.3 ± 0.45 | 3.0 ± 0.55 | 2.1 (2.2) | 3.0 (3.1) |
| MRT (ms) | 394 ± 11.8 | 403 ± 12.1 | 392 (393) | 400 (400) | |
| SDRT (ms) | 98 ± 9.7 | 107 ± 8.6 | 90 (91) | 100 (100) | |
| 10–60 | EP (%) | 2.0 ± 0.39 | 3.0 ± 0.38 | 2.0 (1.8) | 3.0 (2.3) |
| MRT(ms) | 374 ± 5.1 | 377 ± 5.4 | 368 (368) | 377 (373) | |
| SDRT (ms) | 86 ± 5.3 | 88 ± 4.7 | 77 (76) | 88 (83) | |
| 20–50 | EP (%) | 1.9 ± 0.28 | 2.2 ± 0.36 | 2.0 (1.6) | 2.7 (2.3) |
| MRT (ms) | 368 ± 5.1 | 375 ± 5.8 | 367 (368) | 372 (373) | |
| SDRT (ms) | 86 ± 5.1 | 95 ± 5.9 | 77 (75) | 84 (83) | |
| 30–40 | EP (%) | 2.1 ± 0.35 | 2.4 ± 0.42 | 2.1 (1.9) | 2.4 (2.1) |
| MRT (ms) | 370 ± 5.4 | 374 ± 5.8 | 369 (369) | 370 (371) | |
| SDRT (ms) | 91 ± 4.8 | 90 ± 5.2 | 79 (78) | 81 (80) | |

Figure 3
Upper row of graphs: observed (filled and open circles) and predicted (continuous and dashed lines) bin means in the format of cumulative distribution functions for congruent (filled and continuous) and incongruent (open and dashed) conditions. Lower row of graphs: Observed (filled circles) delta plots with 95% confidence range (t distributions) and predicted delta plots (continuous lines). Above each column of graphs stimulus sizes are given.
Table 4
Observed and predicted results for Exp. 1; predicted results are those of Model B (predictions of Model A are in brackets).
| OBSERVED | PREDICTED | ||||
|---|---|---|---|---|---|
| SOA (MS) | CONGRUENT | INCONGRUENT | CONGRUENT | INCONGRUENT | |
| –200 | EP (%) | 5.4 ± 0.91 | 9.5 ± 1.23 | 3.4 (5.3) | 10.6 (9.4) |
| MRT (ms) | 550 ± 5.5 | 575 ± 6.8 | 549 (557) | 567 (561) | |
| SDRT (ms) | 71 ± 4.1 | 67 ± 3.7 | 63 (60) | 59 (60) | |
| –100 | EP (%) | 4.9 ± 0.77 | 11.2 ± 1.47 | 3.5 (4.0) | 12.4 (11.2) |
| MRT (ms) | 462 ± 6.2 | 492 ± 6.6 | 461 (469) | 487 (478) | |
| SDRT (ms) | 74 ± 4.1 | 66 ± 3.6 | 64 (56) | 64 (56) | |
| 0 | EP (%) | 1.3 ± 0.44 | 3.2 ± 0.79 | 0.7 (0.3) | 3.7 (3.2) |
| MRT (ms) | 361 ± 5.5 | 387 ± 6.2 | 358 (360) | 385 (385) | |
| SDRT (ms) | 71 ± 3.7 | 71 ± 5.2 | 59 (50) | 63 (61) | |
| +100 | EP (%) | 0.8 ± 0.35 | 2.5 ± 0.50 | 0.7 (0.6) | 2.6 (2.8) |
| MRT (ms) | 384 ± 6.9 | 410 ± 7.2 | 383 (385) | 409 (409) | |
| SDRT (ms) | 65 ± 4.9 | 72 ± 4.2 | 60 (60) | 67 (66) | |
| +200 | EP (%) | 1.3 ± 0.40 | 2.4 ± 0.50 | 1.0 (0.9) | 2.8 (2.6) |
| MRT (ms) | 395 ± 6.0 | 413 ± 8.7 | 394 (393) | 410 (412) | |
| SDRT (ms) | 73 ± 4.0 | 87 ± 4.7 | 68 (71) | 80 (81) | |
Table 5
Observed and predicted results for Exp. 2; predicted results are those of Model B (predictions of Model A are in brackets).
| OBSERVED | PREDICTED | ||||
|---|---|---|---|---|---|
| SOA (MS) | CONGRUENT | INCONGRUENT | CONGRUENT | INCONGRUENT | |
| –300 | EP (%) | 7.1 ± 1.39 | 8.7 ± 1.38 | 5.9 (7.1) | 8.9 (8.8) |
| MRT (ms) | 656 ± 6.1 | 666 ± 7.3 | 656 (659) | 663 (661) | |
| SDRT (ms) | 63 ± 3.1 | 70 ± 5.3 | 56 (53) | 54 (54) | |
| –150 | EP (%) | 6.3 ± 1.27 | 8.2 ± 1.15 | 4.9 (5.2) | 9.3 (9.1) |
| MRT (ms) | 518 ± 5.5 | 538 ± 7.3 | 521 (523) | 530 (527) | |
| SDRT (ms) | 70 ± 5.2 | 63 ± 4.8 | 55 (51) | 53 (50) | |
| 0 | EP (%) | 1.7 ± 0.43 | 6.1 ± 0.81 | 1.1 (0.5) | 6.2 (6.3) |
| MRT (ms) | 375 ± 6.8 | 403 ± 6.7 | 374 (373) | 399 (398) | |
| SDRT (ms) | 64 ± 4.1 | 68 ± 4.1 | 51 (51) | 54 (54) | |
| +150 | EP (%) | 1.0 ± 0.26 | 2.0 ± 0.52 | 0.7 (0.5) | 2.0 (1.8) |
| MRT (ms) | 406 ± 7.9 | 422 ± 7.8 | 403 (402) | 422 (420) | |
| SDRT (ms) | 67 ± 4.0 | 79 ± 5.7 | 57 (58) | 79 (66) | |
| +300 | EP (%) | 1.3 ± 0.35 | 1.0 ± 0.34 | 1.0 (1.1) | 1.5 (1.8) |
| MRT (ms) | 421 ± 10.2 | 421 ± 10.5 | 416 (417) | 419 (419) | |
| SDRT (ms) | 75 ± 4.3 | 85 ± 4.6 | 63 (63) | 67 (69) | |

Figure 4
upper and lower row of graphs: Observed and predicted bin means of Exp. 1 plotted as cumulative distribution functions. Filled and open circles show observed means in congruent and incongruent conditions for each SOA, continuous and dashed lines show predicted means of model A (upper row) and Model B (lower row) for congruent and incongruent conditions, respectively. Middle row of graphs: Observed delta plots (filled circles) with 95% confidence band and predicted delta plots by Model A (continuous line) and model B (dotted line).

Figure 5
upper and lower row of graphs: Observed and predicted bin means of Exp. 2 plotted as cumulative distribution functions. Filled and open circles show observed means in congruent and incongruent conditions for each SOA, continuous and dashed lines show predicted means of model A (upper row) and Model B (lower row) for congruent and incongruent conditions, respectively. Middle row of graphs: Observed delta plots (filled circles) with 95% confidence band and predicted delta plots by Model A (continuous line) and model B (dotted line).
Table 6
Exp. 1, Parameter estimates for Model B (in brackets for model A). Congruent and incongruent conditions differed only in the algebraic sign of ΔIirr, positive values for congruent and negative values for incongruent conditions, respectively. Time parameters (δ, μD, wD, μR, and wR) are in seconds.
| SOA (MS) | |||||
|---|---|---|---|---|---|
| PARAMETER | –200 | -100 | 0 | +100 | +200 |
| λ | .256 (.259) | .241 (.273) | .263 (.253) | .207 (.232) | .237 (.235) |
| β | .211 (.226) | .220 (.232) | .194 (.234) | .210 (.215) | .243 (.232) |
| σn | .184 (.199) | .202 (.203) | .222 (.234) | .257 (.266) | .235 (.258) |
| Irel | 1.172 (.721) | .946 (.719) | .941 (.807) | .790 (.779) | .709 (.725) |
| ΔIirr | ±.136 (.258) | ±.151 (.242) | ±.127 (±.221) | ±.141 (±.185) | ±.106 (±.094) |
| δ | .065 (.139) | .069 (.135) | .105 (.124) | .072 (.074) | .100 (.086) |
| μD | –.104 (–.095) | –.084 (–.095) | –.081 (–.081) | –.101 (–.085) | -.059 (-.103) |
| wD | .170 (.131) | .194 (.121) | .240 (.132) | .215 (.227) | .203 (.219) |
| θ | 1.271 (.447) | 1.090 (.479) | 1.074 (.736) | 1.076 (.964) | 1.011 (1.071) |
| μR | .202 (.197) | .224 (.206) | .185 (.185) | .218 (.224) | .214 (.208) |
| wR | .076 (.140) | .090 (.124) | .081 (.107) | .093 (.049) | .119 (.103) |
| costs | 9.6 (12.3) | 8.5 (13.9) | 7.5 (9.6) | 3.0 (2.5) | 4.0 (3.5) |
Table 7
Exp. 2, Parameter estimates for Model B (in brackets for model A). Congruent and incongruent conditions differed only in the algebraic sign of ΔIirr, positive values for congruent and negative values for incongruent conditions, respectively. Time parameters (δ, μD, wD, μR, and wR) are in seconds.
| SOA (MS) | |||||
|---|---|---|---|---|---|
| PARAMETER | –300 | –150 | 0 | +150 | +300 |
| λ | .180 (.216) | .187 (.257) | .228 (.224) | .233 (.191) | .225 (.224) |
| β | .128 (.253) | .196 (.242) | .184 (.214) | .198 (.168) | .200 (.237) |
| σn | .153 (.245) | .160 (.205) | .217 (.217) | .247 (.251) | .241 (.238) |
| Irel | 1.215 (.726) | 1.106 (.736) | .996 (.765) | .775 (.759) | .735 (.729) |
| ΔIirr | .054 (.263) | .055 (.277) | .146 (.256) | .099 (.104) | .064 (.207) |
| δ | .068 (.136) | .075 (.119) | .097 (.103) | .078 (.104) | .145 (.122) |
| μD | –.120 (–.100) | –.110 (–.102) | –.098 (–.093) | –.096 (–.090) | -.082 (-.029) |
| wD | .136 (.110) | .143 (.108) | .209 (.081) | .307 (.266) | .229 (.163) |
| θ | 1.584 (.596) | 1.216 (.437) | 1.040 (.687) | 1.019 (1.072) | 1.013 (1.008) |
| μR | .198 (.172) | .221 (.211) | .209 (.190) | .241 (.231) | .244 (.242) |
| wR | .084 (.091) | .101 (.112) | .057 (.117) | .083 (.078) | .110 (.096) |
| costs | 5.4 (4.1) | 8.5 (10.0) | 4.3 (6.3) | 3.1 (3.5) | 4.7 (4.0) |
