Developmental trends of auditory novelty oddball P3 while accounting for N2 in 7- to 25-year-olds.

Many previous studies examining developmental trends in P3 amplitude or latency have used a two-stimulus (standard and target) oddball paradigm. Fewer studies exist using the novelty oddball paradigm, a three-tone (standard, target, and novel) paradigm. In this study with 204 typically developing participants aged 7-25 years, the influence of participant traits-age and sex-on the developmental trends of P3 peak-to-peak amplitude and latency were examined. Additionally, interactions between the three tones of the novelty oddball paradigm and scalp sites on P3 amplitude and latency were evaluated. While previous studies using baseline-to-peak measures have shown smaller P3 amplitude in children compared with adults, this study, using peak-to-peak measures (P3 minus N2 amplitude), found the opposite effect with children having larger P3 amplitudes than adults. This finding is explained by further analyses of N2, representing discrimination. N2 baseline-to-peak amplitude significantly predicted P3 baseline-to-peak amplitude; a mediation effect such that as N2 becomes less negative, P3 becomes larger. Regression analyses revealed that developmental trends of the P3 amplitude were primarily linear, but trends in P3 latency were mostly non-linear. Sex differences were observed, although limited to latency measures. Results from ancovas found significant interactions between the three tones and between frontal (Fz) and parietal (Pz) sites, with larger P3 amplitude during target and novel tones at Pz than Fz, and larger amplitudes during frequent tones at Fz than Pz. These findings highlight the importance of considering more than P3 amplitude in understanding developmental trends in cognitive processing during oddball paradigms.

Revised and Neuroimaging-Compatible Versions of the Dual Task Screen.

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild traumatic brain injury (mTBI). However, past dual task paradigms have focused solely on lower extremity skills and have relied on cumbersome, expensive laboratory equipment - thus limiting their practicality for everyday mTBI evaluation. Subsequently, we developed the Dual Task Screen (DTS), which takes <10 minutes to administer and score, uses low-cost portable equipment, and includes lower extremity (LE) and upper extremity (UE) subtasks. The purpose of this manuscript was twofold. First, we describe the administration protocol for the revised DTS, which we revised to address the limitations of the original DTS. Specifically, the revisions included additions of smart devices to acquire more detailed gait data and inclusion of single cognitive conditions to test for disrupted cognitive performance under dual task conditions. Importantly, the revised DTS is a measure intended for future clinical use, and we present representative results from three male athletes to illustrate the type of clinical data that can be acquired from the measure. Importantly, we have yet to evaluate the sensitivity and specificity of the revised DTS in athletes with mTBI, which is the next research initiative. The second purpose of this manuscript is to describe a neuroimaging-compatible version of the DTS. We developed this version so we could evaluate the neural underpinnings of single and dual task performance, for a better empirical understanding of the behavioral deficits associated with mTBI. Thus, this manuscript also describes the steps we took to enable simultaneous functional near-infrared spectroscopy (fNIRS) measurement during the DTS, along with how we acquired and completed first-level processing of the fNIRS data.