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Abnormal Parietal Brain Function in ADHD: Replication and Extension of Previous EEG Beta Asymmetry Findings.

Hale TS, Kane AM, Tung KL, Kaminsky O, McGough JJ, Hanada G, Loo SK - Front Psychiatry (2014)

Bottom Line: We additionally examined: (a) EEG asymmetry in multiple frequency bands, (b) unilateral effects for all asymmetry findings, and (c) the association between EEG asymmetry and a battery of cognitive tests.Novel analyses also demonstrated a broader pattern of rightward beta and theta asymmetry across inferior, superior, and temporal-parietal brain regions, and showed that rightward parietal asymmetry in ADHD was atypically associated with multiple cognitive tests.We speculate that this phenotype may occur with any form of impaired capacity for top-down task-directed control over sensory encoding functions, and that it may reflect associated increase of attentional shifting and compensatory sustained/selective attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry and Biobehavioral Sciences, UCLA Semel Institute for Neuroscience and Human Behavior , Los Angeles, CA , USA.

ABSTRACT

Background: Abundant work indicates ADHD abnormal posterior brain structure and function, including abnormal structural and functional asymmetries and reduced corpus callosum size. However, this literature has attracted considerably less research interest than fronto-striatal findings.

Objective: To help address this imbalance, the current study replicates and extends our previous work showing abnormal parietal brain function in ADHD adults during the Conner's Continuous Performance Test (CPT).

Method: Our previous study found that ADHD adults had increased rightward EEG beta (16-21 Hz) asymmetry in inferior parietal brain regions during the CPT (p = 0.00001), and that this metric exhibited a lack of normal correlation (i.e., observed in controls) with beta asymmetry at temporal-parietal regions. We re-tested these effects in a new ADHD sample and with both new and old samples combined. We additionally examined: (a) EEG asymmetry in multiple frequency bands, (b) unilateral effects for all asymmetry findings, and (c) the association between EEG asymmetry and a battery of cognitive tests.

Results: We replicated our original findings by demonstrating abnormal rightward inferior parietal beta asymmetry in adults with ADHD during the CPT, and again this metric exhibited abnormal reduced correlation to temporal-parietal beta asymmetry. Novel analyses also demonstrated a broader pattern of rightward beta and theta asymmetry across inferior, superior, and temporal-parietal brain regions, and showed that rightward parietal asymmetry in ADHD was atypically associated with multiple cognitive tests.

Conclusion: Abnormal increased rightward parietal EEG beta asymmetry is an important feature of ADHD. We speculate that this phenotype may occur with any form of impaired capacity for top-down task-directed control over sensory encoding functions, and that it may reflect associated increase of attentional shifting and compensatory sustained/selective attention.

No MeSH data available.


Related in: MedlinePlus

Distribution of absolute power in beta2 frequency band (16–21 Hz) among parietal electrodes comprising parietal asymmetry indices. Figure 1 shows EEG data recorded during the CPT, and indicates the spread of beta2 (16–21 Hz) power (μv2) among parietal electrodes comprising parietal asymmetry indices (TP7, P7, P3, TP8, P8, P4). Note the leftward distribution of power in controls compared to ADHD.
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Figure 1: Distribution of absolute power in beta2 frequency band (16–21 Hz) among parietal electrodes comprising parietal asymmetry indices. Figure 1 shows EEG data recorded during the CPT, and indicates the spread of beta2 (16–21 Hz) power (μv2) among parietal electrodes comprising parietal asymmetry indices (TP7, P7, P3, TP8, P8, P4). Note the leftward distribution of power in controls compared to ADHD.

Mentions: Examination of multiple frequency bands and AIs across the scalp demonstrated several instances of atypical rightward parietal asymmetry in ADHD. Rightward parietal asymmetry in ADHD subjects was evident at the temporal–parietal AI (TP8–TP7) in theta, beta1, and beta2 frequency bands, the inferior parietal AI (P8–P7) in the beta2 frequency band, and the superior-parietal AI (P4–P3) in theta and beta2 frequency bands (Table 5; Figure 1). As in our previous study, the P8–P7 AI only showed ADHD/control group differences in the beta2 frequency band. There were no significant effects showing leftward parietal asymmetry in ADHD. However, a trend effect indicated ADHD leftward frontal asymmetry (F8–F7) in the beta2 band, which is reported due to a conceptual interest.


Abnormal Parietal Brain Function in ADHD: Replication and Extension of Previous EEG Beta Asymmetry Findings.

Hale TS, Kane AM, Tung KL, Kaminsky O, McGough JJ, Hanada G, Loo SK - Front Psychiatry (2014)

Distribution of absolute power in beta2 frequency band (16–21 Hz) among parietal electrodes comprising parietal asymmetry indices. Figure 1 shows EEG data recorded during the CPT, and indicates the spread of beta2 (16–21 Hz) power (μv2) among parietal electrodes comprising parietal asymmetry indices (TP7, P7, P3, TP8, P8, P4). Note the leftward distribution of power in controls compared to ADHD.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109587&req=5

Figure 1: Distribution of absolute power in beta2 frequency band (16–21 Hz) among parietal electrodes comprising parietal asymmetry indices. Figure 1 shows EEG data recorded during the CPT, and indicates the spread of beta2 (16–21 Hz) power (μv2) among parietal electrodes comprising parietal asymmetry indices (TP7, P7, P3, TP8, P8, P4). Note the leftward distribution of power in controls compared to ADHD.
Mentions: Examination of multiple frequency bands and AIs across the scalp demonstrated several instances of atypical rightward parietal asymmetry in ADHD. Rightward parietal asymmetry in ADHD subjects was evident at the temporal–parietal AI (TP8–TP7) in theta, beta1, and beta2 frequency bands, the inferior parietal AI (P8–P7) in the beta2 frequency band, and the superior-parietal AI (P4–P3) in theta and beta2 frequency bands (Table 5; Figure 1). As in our previous study, the P8–P7 AI only showed ADHD/control group differences in the beta2 frequency band. There were no significant effects showing leftward parietal asymmetry in ADHD. However, a trend effect indicated ADHD leftward frontal asymmetry (F8–F7) in the beta2 band, which is reported due to a conceptual interest.

Bottom Line: We additionally examined: (a) EEG asymmetry in multiple frequency bands, (b) unilateral effects for all asymmetry findings, and (c) the association between EEG asymmetry and a battery of cognitive tests.Novel analyses also demonstrated a broader pattern of rightward beta and theta asymmetry across inferior, superior, and temporal-parietal brain regions, and showed that rightward parietal asymmetry in ADHD was atypically associated with multiple cognitive tests.We speculate that this phenotype may occur with any form of impaired capacity for top-down task-directed control over sensory encoding functions, and that it may reflect associated increase of attentional shifting and compensatory sustained/selective attention.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry and Biobehavioral Sciences, UCLA Semel Institute for Neuroscience and Human Behavior , Los Angeles, CA , USA.

ABSTRACT

Background: Abundant work indicates ADHD abnormal posterior brain structure and function, including abnormal structural and functional asymmetries and reduced corpus callosum size. However, this literature has attracted considerably less research interest than fronto-striatal findings.

Objective: To help address this imbalance, the current study replicates and extends our previous work showing abnormal parietal brain function in ADHD adults during the Conner's Continuous Performance Test (CPT).

Method: Our previous study found that ADHD adults had increased rightward EEG beta (16-21 Hz) asymmetry in inferior parietal brain regions during the CPT (p = 0.00001), and that this metric exhibited a lack of normal correlation (i.e., observed in controls) with beta asymmetry at temporal-parietal regions. We re-tested these effects in a new ADHD sample and with both new and old samples combined. We additionally examined: (a) EEG asymmetry in multiple frequency bands, (b) unilateral effects for all asymmetry findings, and (c) the association between EEG asymmetry and a battery of cognitive tests.

Results: We replicated our original findings by demonstrating abnormal rightward inferior parietal beta asymmetry in adults with ADHD during the CPT, and again this metric exhibited abnormal reduced correlation to temporal-parietal beta asymmetry. Novel analyses also demonstrated a broader pattern of rightward beta and theta asymmetry across inferior, superior, and temporal-parietal brain regions, and showed that rightward parietal asymmetry in ADHD was atypically associated with multiple cognitive tests.

Conclusion: Abnormal increased rightward parietal EEG beta asymmetry is an important feature of ADHD. We speculate that this phenotype may occur with any form of impaired capacity for top-down task-directed control over sensory encoding functions, and that it may reflect associated increase of attentional shifting and compensatory sustained/selective attention.

No MeSH data available.


Related in: MedlinePlus