Measuring interference effects in numerical cognition Gabor Lengyel

Measuring interference effects in numerical cognition Gabor Lengyel & Attila Krajcsi

Searching for the PNARC effect – the SNARC • SNARC (Dehaene et al. 1993) (Spatial-Numerical Association of Response Codes) small– 1 2 3 4 5 6 7 8 9 -large Parity judgement task Odd or even ? 6 • Explanation 1. Analog (Dehaene et al. 1993, Cantlon et al. 2009) 2. Discrete (Proctor & Cho 2006, Nuerk et al. 2004)

Searching for the PNARC effect – the MARC • MARC (Nuerk et al. 2004) (Markedness Association of Response Code) Odd Even Discrete representation Parity judgement task ?

Searching for the PNARC effect • PNARC (Krajcsi et al. 2018) (Parity-Numerical Association of Representational Codes) small– 1 2 3 4 5 6 7 8 9 -large Odd Even Discrete representation Parity judgement task ?

Measuring interference effects 1. Classical Single Index Method

Single index method - SNARC Subject_28 Right response SNARC Left response small– 1 2 3 4 5 6 7 8 9 -large Left Right - Left response Right RT = Slope * (RT_right-RT_left) + intercept Single index = Slope

Single index method - PNARC Subject_28 Even response PNARC Odd response small– 1 2 3 4 5 6 7 8 9 -large Slope_odd = 9 Slope_even = -7 Odd Even Single index = Slope_odd – Slope_even = -16

Experiment - no PNARC effect • Parity judgement task • N = 54 • SNARC • Slope_95%CI = [2. 48, 5. 41], t(53) = 5. 4, p <. 001 • MARC • Slope_95%CI = [23. 72, -10. 63], t(53) = 0. 764, p =. 448 • PNARC • Slope_95%CI = [-1. 03, 3. 69], t(53) = 1. 13, p =. 265

Measuring interference effects 2. New Dual Index Method

Heterogeneous interferences - Dual index Slope_even > 0 Correlation (Slope_odd, Slope_even) < 0 Heterogeneous interference Slope_odd < 0 Subject_13 Slope_even < 0 Subject_28 Slope_odd > 0

The Dual and Single indices Slope_even > 0 Slope_odd < 0 Slope even Subject_13 Slope_even < 0 Subject_28 Slope odd Slope_odd > 0

Experiment - PNARC effect SNARC • Single index • t(53) = 5. 4, p <. 001 • Dual Index • r(52) = 0. 004, p =. 975 • Parity judgement task • N = 54 MARC • Single index • t(53) = 0. 764, p =. 448 • Dual Index • r(52) = -0. 432, p =. 001 PNARC • Single index • t(53) = 1. 13, p =. 265 • Dual Index • r(52) = -0. 461, p <. 001

Summary – Single & Dual Indices • Single Index = 0 • Dual Index = 0 Noise • Single Index > 0 • Dual Index < 0 or • Dual Index > 0 Homogeneous • Single Index = 0 • Dual Index < 0 Heterogeneous

Thank you! For more detail: Krajcsi, Lengyel & Laczko (2018). Interference Between Number Magnitude and Parity: Discrete Representation in Number Processing. Experimental Psychology, 65, pp. 71 -83. https: //doi. org/10. 1027/16183169/a 000394