Deficient information processing in ADHD theoretically results in sensory overload and may underlie the symptoms of the disorder. Mismatch negativity (MMN) and P3a amplitude reflect an individual's detection and subsequent change in attention to stimulus change in their environment. Our primary aim was to explore MMN and P3a amplitude in adult ADHD patients and to examine the effects of methylphenidate (MPH) on these measures.

Forty initially psychostimulant-naïve, adult ADHD patients without comorbid ASD and 42 matched healthy controls (HC) were assessed with an MMN paradigm at baseline. Both groups were retested after 6 weeks, in which patients were treated with MPH.

Neither significant group differences in MMN nor P3a amplitude were found at baseline. Although 6-week MPH treatment significantly reduced symptomatology and improved daily functioning of the patients, it did not significantly affect MMN amplitude; however, it did significantly reduce P3a amplitude compared to the HC. Furthermore, more severe ADHD symptoms were significantly associated with larger MMN amplitudes in the patients, both at baseline and follow-up.

We found no evidence for early information processing deficits in patients with ADHD, as measured with MMN and P3a amplitude. Six-week treatment with MPH decreased P3a but not MMN amplitude, although more severe ADHD-symptoms were associated with larger MMN amplitudes in the patients. Given that P3a amplitude represents an important attentional process and that glutamate has been linked to both ADHD and MMN amplitude, future research should investigate augmenting MPH treatment of less responsive adults with ADHD with glutamatergic antagonists.

ADHD 中的信息处理不足理论上会导致感觉超负荷，并且可能是该疾病症状的基础。失配负性 (MMN) 和 P3a 振幅反映了个体对其环境中刺激变化的检测和随后的注意力变化。我们的主要目的是探索成人 ADHD 患者的 MMN 和 P3a 振幅，并检查哌醋甲酯 (MPH) 对这些措施的影响。

在基线时使用 MMN 范式评估了 40 名最初未使用过精神兴奋剂的成年 ADHD 患者，没有共病 ASD 和 42 名匹配的健康对照 (HC)。两组均在 6 周后重新测试，其中患者接受 MPH 治疗。

在基线时未发现 MMN 和 P3a 振幅的显着组间差异。尽管 6 周的 MPH 治疗显着减轻了症状并改善了患者的日常功能，但并未显着影响 MMN 波幅；然而，与 HC 相比，它确实显着降低了 P3a 振幅。此外，更严重的 ADHD 症状与患者中更大的 MMN 振幅显着相关，无论是在基线还是随访中。

我们没有发现 ADHD 患者早期信息处理缺陷的证据，如用 MMN 和 P3a 振幅测量的那样。为期六周的 MPH 治疗降低了 P3a 而不是 MMN 振幅，尽管更严重的 ADHD 症状与患者中更大的 MMN 振幅相关。鉴于 P3a 振幅代表一个重要的注意过程，并且谷氨酸与 ADHD 和 MMN 振幅有关，未来的研究应该研究用谷氨酸能拮抗剂增加 MPH 治疗反应较差的 ADHD 成人。