Trait inattention and goal representations.

Inattention is a symptom of many clinical disorders. Research has shown that the symptom of inattention is best thought of as being on a continuum. Consistently, sub- clinical inattention has been shown to be related to impairments in working memory, particularly those functions related to goal maintenance. In six studies, the link between trait inattention and working memory limitations was investigated with the aim of differentiating inattention from hyperactivity and impulsivity, which are commonly comorbid with inattention in ADHD. Across two studies, it was found that trait inattention predicted the daily life reports of mind wandering. However, this relationship was also observed in hyperactive and impulsive traits. Unique relationships were however observed between trait inattention and goal neglect (as measured by a letter-monitoring task). Furthermore, it was found that inattentive traits uniquely predicted decreased performance on task switching and Stroop tasks where the use of goal maintenance (proactive control) would be beneficial to task performance; and goal neglect mediated these relationships. I discuss how these findings relate to the inattention, goal neglect and proactive control literatures. The key finding was the consistent replication of the unique link between inattention and goal neglect frequency (Chapter 3, Chapter 5), and the role that goal neglect plays in producing impairments in proactive control use

Inhibitory control ability moderates the relationship between internet addiction and inattention in ADHD in a community sample

Internet addiction (IA) has been related to psychiatric problems such as ADHD. However, it is not known exactly how this relationship operates, although most research shows that both people with ADHD and IA have inhibitory control (IC) deficit. This study aimed to investigate whether IC mediates or moderates the relationship. 76 non-clinically diagnosed participants were recruited. They performed the Stroop task and completed the Young's Internet Addiction Test, Adult ADHD Self-Report Scale Symptom Checklist and a Demographic Information Form. Consistent with previous research, the results show that while total ADHD/inattention was correlated with IA, hyperactivity/impulsivity was not. In contrast with some previous research, Stroop task performance (measured via reaction times and pupil dilation) did not differ between low and high IA groups, nor low and high inattention groups. Despite neither inattention nor IA between associated with IC impairments, the relationship between inattention and IA was shown to be moderated by Stroop task performance in that the relationship was present mainly in those who experience high and moderate IC deficits. This finding could have implications for both ADHD and IA at higher levels of severity and could help guide prevention and treatment options in those most vulnerable to IA

The effect of high-frequency rTMS of the left dorsolateral prefrontal cortex on the resolution of response, semantic and task conflict in the colour-word Stroop task.

Previous work investigating the effect of rTMS of left Dorso-Lateral Prefrontal Cortex (DLPFC) on Stroop task performance reports no changes to the Stroop effect but reduced reaction times on both congruent and incongruent trials relative to sham stimulation; an effect attributed to an enhanced attentional (or task) set for colour classification. The present study tested this account by investigating whether, relative to vertex stimulation, rTMS of the left DLPFC modifies task conflict, a form of conflict that arises when task sets for colour classification and word reading compete, given that this particular type of conflict would be reduced by an enhanced task set for colour classification. Furthermore, the present study included measures of other forms of conflict present in the Stroop task (response and semantic conflict), the potential effects on which would have been hidden in previous studies employing only incongruent and congruent stimuli. Our data showed that left DLPFC stimulation had no effect on the magnitude of task conflict, nor did it affect response, semantic or overall conflict (where the null is supported by sensitive Bayes Factors in most cases). However, consistent with previous research left DLPFC stimulation had the general effect of reducing reaction times. We therefore show for the first time that relative to real vertex stimulation left DLPFC stimulation does not modify Stroop interference. Alternative accounts of the role of the left DLPFC in Stroop task performance in which it either modifies response thresholds or facilitates responding by keeping the correct response keys active in working memory are discusse

Trait-level non-clinical ADHD symptoms in a community sample and their association with technology addictions

An increasing number of studies have reported the existence of ADHD symptoms to be risk factors for technology addictions among young adults. In contrast to previous studies, the aim of the present study was to examine different dimensions of technology addiction in a community sample of adults and to examine their association with the individual trait-level ADHD symptoms of inattention and hyperactivity-impulsivity. A community sample of one hundred and fifty adults were recruited to participate in this study via convenience sampling. Participants completed the Adult ADHD Self-Report Scale Symptom Checklist, the Bergen Social Media Addiction Scale, the Smartphone Addiction Scale, Young’s Internet Addiction Test, the Compulsive Online Shopping Scale, and a Demographic Information Form. Composite ADHD score, inattention and hyperactivity/impulsivity were positively associated with technology addictions (internet, social media, smartphone, and online shopping addiction). Hierarchical regression analysis revealed inattention and hyperactivity-impulsivity were predictors of social media addiction and smartphone addiction, whereas they were not for online shopping addiction. Furthermore, inattention was the only predictor of internet addiction. People with non-clinical, trait-level ADHD, especially those showing a preponderance of inattention symptoms appear to be more vulnerable to developing some forms of technology addiction

Low-frequency rTMS to the parietal lobe increases eye-movement carryover and decreases hazard rating.

The persistence of attentional set from one task to a secondary unrelated task, revealed through carryover of eye movements, has been attributed to increased activation in the parietal lobe and decreased activation to the frontal lobe. To directly test this, we adopted a modified version of the Thompson and Crundall (2011) paradigm using low-frequency repetitive TMS to P3 and F3. In each trial, participants viewed letter-strings that were arranged horizontally, vertically, or randomly across the screen before viewing a road image and providing a hazardousness rating for it. The orientation of the letter search influenced eye movements to the road images and this carryover was greater following stimulation to F3 than to P3 (or sham). Furthermore, hazardous ratings were lower following P3 stimulation. These results confirm the involvement of attentional orienting and switching mechanisms in the carryover of eye movements. It is suggested that this “attentional inertia” effect will increase with greater orienting of attentional resources in an initial task and poor inhibition of previously-relevant settings between tasks