Error-related event-related potentials in children with attention-deficit hyperactivity disorder, oppositional defiant disorder, reading disorder, and math disorder.

We studied error-related negativity (ERN) and error positivity (Pe) during a discrimination task in 319 unmedicated children divided into subtypes of ADHD (Not-ADHD/inattentive/combined), learning disorder (Not-LD/reading/math/reading+math), and oppositional defiant disorder. Response-locked ERPs contained a frontocentral ERN and posterior Pe. Error-related negativity and positivity exhibited larger amplitude and later latency than corresponding waves for correct responses matched on reaction time.

Effects of methylphenidate on subtypes of attention-deficit/hyperactivity disorder.

Objective: To compare the effects of methylphenidate on attention-deficit/hyperactivity disorder (ADHD) subtypes.

Method: Nineteen ADHD/inattentive (ADHD/I) and 22 ADHD/combined (ADHD/C) 6- to 12-year-old children entered a 6-week, double-blind trial of placebo and methylphenidate in divided doses (0.94 +/- 0.

Performance and private speech of children with attention-deficit/hyperactivity disorder while taking the Tower of Hanoi test: effects of depth of search, diagnostic subtype, and methylphenidate.

We administered the Tower of Hanoi to demographically comparable samples of control participants (n = 34) and children with the Combined (n = 22) and Inattentive subtypes (n = 19) of Attention-Deficit/Hyperactivity Disorder (ADHD). Controls excelled over children with the Inattentive subtype, who outperformed patients with the Combined subtype. These results replicated findings of greater executive deficits in the Combined than in the Inattentive type of ADHD.

Acoustic startle in maltreated children.

We investigated the eyeblink component of acoustic startle reactions in maltreated children. Previous research indicates that acoustic startle is enhanced in adult males with posttraumatic stress disorders (PTSD) whereas findings on women with PTSD have been inconsistent. In accord with the only previous report for children with PTSD, we found that maltreated boys, particularly those who had been physically abused, responded to increases in startle probe loudness with smaller increments in amplitude of startle eyeblink and smaller reductions in blink latency than did comparison boys.

Effects of event probability and sequence on children with attention-deficit/hyperactivity, reading, and math disorder.

Background: We investigated the impact of stimulus probability and sequence on performance and event-related potentials of 310 children classified into 12 combinations of attention-deficit/hyperactivity disorder (Not-attention-deficit/hyperactivity disorder, Inattentive and Combined subtypes) with presence/absence of reading disorder and math disorder.

Methods: Subjects pressed buttons to displays of the letters O and X, which were presented with probabilities of either .17/.