Impact of emotional salience on episodic memory in attention-deficit/hyperactivity disorder: a functional magnetic resonance imaging study.
ABSTRACT Patients with attention-deficit/hyperactivity disorder (ADHD) show episodic memory deficits especially in complex memory tasks. We investigated the neural correlates of memory formation in ADHD and their modulation by stimulus salience.
We recorded event-related functional magnetic resonance imaging during an episodic memory paradigm with neutral and emotional pictures in 12 male ADHD subjects and 12 healthy adolescents.
Emotional salience did significantly augment memory performance in ADHD patients. Successful encoding of neutral pictures was associated with activation of the anterior cingulate cortex (ACC) in healthy adolescents but with activation of the superior parietal lobe (SPL) and precuneus in ADHD patients. Successful encoding of emotional pictures was associated with prefrontal and inferior temporal cortex activation in both groups. Healthy adolescents, moreover, showed deactivation in the inferior parietal lobe.
From a pathophysiological point of view, the most striking functional differences between healthy adolescents and ADHD patients were in the ACC and SPL. We suggest that increased SPL activation in ADHD reflected attentional compensation for low ACC activation during the encoding of neutral pictures. The higher salience of emotional stimuli, in contrast, regulated the interplay between ACC and SPL in conjunction with improving memory to the level of healthy adolescents.
SourceAvailable from: Rosa Angela Fabio[Show abstract] [Hide abstract]
ABSTRACT: Background Episodic autobiographical memory (EAM) has not been extensively investigated in children with attention-deficit/hyperactivity disorder (ADHD). The objective of this study was to examine EAM in school age children with ADHD in reference to the encoding period: recent memories (previous school years) and remote memories (first years of life). Methods A sample of 29 children with ADHD and 29 typically developing children, matched for age and gender, completed a questionnaire to assess EAM. These participants were recruited from an initial sample of 572 participants. Developmental differences in accessing and recalling specific personal events and episodic details in groups with ADHD were predicted. Results The control group showed a typical trend of EAM with fewer remote and episodic memories than recent ones. The ADHD groups showed a general EAM deficit. More precisely, the ADHD-I group performed equally poorly on remote and recent EAMs, whereas the ADHD-C group showed a higher number of remote EAMs than recent ones. Conclusions The findings suggest that EAM can be impaired in children with ADHD. Clinical and medicolegal implications of these results and the relation between age and childhood amnesia are discussed.Journal of Intellectual & Developmental Disability 01/2015; DOI:10.3109/13668250.2014.983057 · 1.02 Impact Factor
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ABSTRACT: Although attention deficit hyperactivity disorders (ADHD) and autism spectrum disorders (ASD) share certain neurocognitive characteristics, it has been hypothesized to differentiate the two disorders based on their brain’s reward responsiveness to either social or monetary reward. Thus, the present fMRI study investigated neural activation in response to both reward types in age and IQ-matched boys with ADHD versus ASD relative to typically controls (TDC). A significant group by reward type interaction effect emerged in the ventral striatum with greater activation to monetary versus social reward only in TDC, whereas subjects with ADHD responded equally strong to both reward types, and subjects with ASD showed low striatal reactivity across both reward conditions. Moreover, disorder-specific neural abnormalities were revealed, including medial prefrontal hyperactivation in response to social reward in ADHD versus ventral striatal hypoactivation in response to monetary reward in ASD. Shared dysfunction was characterized by fronto-striato-parietal hypoactivation in both clinical groups when money was at stake. Interestingly, lower neural activation within parietal circuitry was associated with higher autistic traits across the entire study sample. In sum, the present findings concur with the assumption that both ASD and ADHD display distinct and shared neural dysfunction in response to reward.Developmental Cognitive Neuroscience 08/2014; DOI:10.1016/j.dcn.2014.08.003 · 3.71 Impact Factor
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ABSTRACT: Background Slow oscillations (<1 Hz) during slow wave sleep (SWS) promote the consolidation of declarative memory. Children with attention-deficit/hyperactivity disorder (ADHD) have been shown to display deficits in sleep-dependent consolidation of declarative memory supposedly due to dysfunctional slow brain rhythms during SWS. Objective Using transcranial oscillating direct current stimulation (toDCS) at 0.75 Hz, we investigated whether an externally triggered increase in slow oscillations during early SWS elevates memory performance in children with ADHD. Methods: 12 children with ADHD underwent a toDCS and a sham condition in a double-blind crossover study design conducted in a sleep laboratory. Memory was tested using a 2D object-location task. In addition, 12 healthy children performed the same memory task in their home environment. Results Stimulation enhanced slow oscillation power in children with ADHD and boosted memory performance to the same level as in healthy children. Conclusion These data indicate that increasing slow oscillation power during sleep by toDCS can alleviate declarative memory deficits in children with ADHD.Brain Stimulation 07/2014; 7(6). DOI:10.1016/j.brs.2014.07.036 · 5.43 Impact Factor