Alpha modulation during working memory encoding predicts neurocognitive impairment in ADHD

Abstract

Background Attention‐deficit/hyperactivity disorder (ADHD) is associated with working memory (WM) deficits. However, WM is a multiprocess construct that can be impaired through several pathways, leaving the source of WM impairments in ADHD unresolved. In this study, we aim to replicate, in an independent sample, previously reported deficits in component processes of WM deficits in ADHD and expand to consider their implications for neurocognitive outcomes. Methods In 119 children (7–14 years old, 85 with ADHD), we used electroencephalography measures to quantify component processes during performance of a spatial working memory task. We quantified stimulus encoding using alpha range (8–12 Hz) power; vigilance by the P2 event‐related potential to cues; and WMmaintenance by occipital‐alpha and frontal‐theta (4–7 Hz) power. These measures were evaluated against metrics of executive function, ADHD symptoms, and academic achievement. Results Encoding alpha‐power decreases and cue P2 amplitude were attenuated in ADHD, whereas occipital‐alpha power during maintenance was significantly greater in ADHD, consistent with a compensatory response to weak encoding. Weak alpha modulation during encoding was associated with poorer reading comprehension and executive function, as well as enhanced ADHD symptoms. Previously reported effects in frontal‐theta power failed to replicate. Conclusions Stimulus encoding, a component process of WM coupled to alpha modulation, is impaired in ADHD, and, unlike WM maintenance or vigilance processes, has implications outside of the laboratory via a relationship with executive function, and, to a weaker extent, reading comprehension.

The impact of mild-to-severe hearing loss on the neural dynamics serving verbal working memory processing in children

“…Given that this response typically increases in amplitude with the difficulty of a task, it is possible that at the same level of difficulty, CHL required a higher level of suppression or inhibition in order to properly maintain the stimulus. Interestingly, increases in maintenance-related alpha ERS responses during working memory processing have also been found in ADHD and other related attention disorders ( Lenartowicz et al, 2019 , Missonnier et al, 2013 ); thus, it is possible that this elevation in CHL may be related to altered attention function. Behaviorally speaking, CHL have been shown to be diagnosed with ADHD at higher rates than CNH ( Soleimani et al, 2020 , Theunissen et al, 2014a ), though the literature is relatively variable (see ( Theunissen et al, 2014b )).…”

Neural generators involved in visual cue processing in children with attention‐deficit/hyperactivity disorder (ADHD)

“…In others, auditory selective attention task, larger theta (Yordanova et al, 2006) and reduced mu (Yordanova et al, 2013) evoked by irrelevant (non-targets, non-attended) stimuli were reported. The alpha oscillation presented an attenuated event-related desynchronization (ERD) during the encoding phase and an increased occipital power spectrum during the maintenance phase of a spatial working memory task performed by ADHD children (Lenartowicz et al, 2019). In these patients, an increased parieto-occipital gamma band evoked during the encoding phase of a recognition test (Lenz et al, 2008) that did not correlate with performance (Lenz et al, 2008) or differentiate between the known and unknown items (Lenz et al, 2010) was reported.…”

Linking RDoC and HiTOP: A new interface for advancing psychiatric nosology and neuroscience

“…Maintenance, Interference control), due to high overlap in the elements contained within each subconstruct and difficulty in distinguishing them in empirical studies. A primary link with the Disinhibited Externalizing spectrum and Substance Abuse subfactor is supported by associations of markers of behavioral and paradigms units of analysis with inattentive and hyperactive-impulsive symptoms (Lenartowicz et al, 2019;Michelini et al, 2018;Müller et al, 2015;Polner et al, 2015) and with substance use escalation (Khurana et al, 2013;Peeters et al, 2014;Squeglia et al, 2014), captured by the Substance Abuse subfactor. Similar associations with externalizing problems further suggest a primary link to the Antisocial Behavior subfactor (Agnes Brunnekreef et al, 2007;Huang-Pollock et al, 2017).…”