Unconscious math

Can we do math unconsciously? A study by Rusconi et al. demonstrates that in a neglect patient, neglect does not prevent neglected numbers from accessing their representations in arithmetic networks. Doing simple math, like reading, seems to be highly automatic.

Arithmetic priming from neglected numbers

Elena Rusconi et al. in Cognitive Neuropsychology Volume 23, Number 2 / 2006, 227 – 239

Abstract:

Patient AM, with left visuospatial neglect, and 31 healthy participants performed a parity judgment task on numbers presented to their right parafovea. Target numbers were preceded by a pair of digits (prime) appearing peripherally for 100 ms either in their left (LVF) or in their right visual field (RVF), which participants had to ignore. In healthy participants, when primes were arithmetically related to the following target, performance was significantly slower than when primes and targets were not related. In contrast, AM’s performance was slower in the related than in the control condition when prime digits appeared in his RVF, whereas it was faster in the related than in the control condition when prime digits appeared in his LVF. This suggests that neglected numbers were nevertheless processed at least until the level of stored arithmetic knowledge. Thus, visuospatial neglect does not prevent neglected numbers from accessing their representations in arithmetic networks, which seems to be a highly automatised skill. Moreover, AM’s pattern of data (i.e., interference from RVF primes vs. facilitation from LVF primes) supports the hypothesis of a link between conscious attention and inhibitory processes, as proposed by Fuentes and Humphreys (1996).

Psychology Press