The application of the two-choice oddball paradigm to the research of behavioral inhibitory control

Abstract

Behavioral inhibitory control (BIC) refers to one’s inhibitory control of impulsive, context-inappropriate behavioral patterns, which is of vital importance to humans’ adaptation to the changing environment. Go/Nogo paradigm and Stop Signal paradigm are the two widely used paradigms for the studies of behavioral inhibitory control and its cognitive neuroscience underpinnings. In a typical Go/Nogo task, the presentation of go stimulus requires a motor response, which however should be suppressed during Nogo stimulus presentation. As a result, behavioral indicators of BIC and its inter- or intra-individual differences, in most cases, depend solely on the accuracy difference between Go and Nogo conditions, which is sometimes insensitive to inhibitory processing. Also, it is difficult to control the obscuring effects of motor preparation/execution on the interpretation of BIC-related neural activities by a simple Go-Nogo comparison. On the other hand, the stop signal paradigm uses a staircase method to vary the stop-signal delay from the go signal to the stop-signal, to manipulate participants’ successful stop and erroneous response at around 50% of the trials, respectively. This method is used to compute stop-signal reaction time (SSRT), an index considered to reflect one’s behavioral inhibitory function. However, this method sacrifices the analysis and the interpretation of accuracy data and, again, the stop-signal paradigm meets difficulty in controlling the contaminations of a preceding go stimulus processing on the neural processing of the subsequent stop signal. Based on these considerations, we introduced a novel two-choice oddball paradigm for overcoming the limitations of the above paradigms, and for the acquisition of more comprehensive and sensitive behavioral markers of BIC. Using reaction time cost (RT Cost) and accuracy cost as behavioral indexes, relevant empirical studies have shown that the new paradigm can be validly used for the psychological and cognitive neuroscience studies of BIC in the following three domains: (i) to detect inter-individual differences in BIC (e.g. sex differences) by both behavioral and neurophysiological markers; (ii) to detect intra-individual differences in BIC as a function of internal state changes (e.g. emotion); (iii) to assess the impairment and the functional plasticity of impulse inhibition in drug addiction (e.g. nicotine addiction). These evidences suggest that the two-choice oddball paradigm can be widely used to assess behavioral inhibitory function and its variability, in the broad area of psychology and cognitive neuroscience research.