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Semantic influences on object detection: Drift diffusion modeling provides insights regarding mechanism

Fig 3

Different cases of drift diffusion model.

(A) A basic drift diffusion model over time. The x-axis represents time in seconds, and the y-axis represents evidence accumulation, which could be a cognitive or a perceptual process leading towards a decision. The dashed lines at the top and bottom represent decision thresholds for two choices, labeled as “Right” and “Left”, denoting by and separately. Evidence accumulates over time, starting from and fluctuating until it reaches one of the thresholds, indicating a decision has been made. The double headed arrow denotes the non-decision time, . In A, the evidence crosses the upper threshold, suggesting a decision made towards the “Right side” option. (B) A decision process with a positive drift rate, v, on evidence accumulation (v > 0). A positive drift rate indicates a tendency for the evidence to accumulate towards the “Right side” choice over time. (C) A negative drift rate (v < 0) indicates a tendency to accumulate evidence towards the “Left side” choice. (D) A lower signal-to-noise ratio where there is more variability and noise in the evidence accumulation process than in C, resulting in a longer path to a decision threshold. (E) A higher threshold condition where more evidence must be accumulated before decision. (F) Evidence accumulation begins with a bias towards the “Right” choice, starting above zero, indicating a predisposition towards that option. (G) The opposite initial bias towards the “Left” choice, with evidence accumulation starting below zero.

doi: https://doi.org/10.1371/journal.pcbi.1012269.g003