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Reward and punishment processing are subject to substantial developmental changes during youth. However, little is known about the neurophysiological correlates that are associated with these developmental changes, particularly with regard to both anticipatory and outcome processing stages. Thus, the aim of this study was to address this research gap in a sample of typically developing children and adolescents. Fifty-four children and adolescents (8-18 years) performed a Monetary Incentive Delay Task comprising a monetary reward and punishment condition. Using event-related brain potential recordings, the cue-P3 and the stimulus-preceding negativity (SPN) were analyzed during the anticipation phase, while the Reward Positivity and the feedback-P3 were analyzed during the outcome phase. When anticipating monetary loss or no gain, SPN amplitude in the right hemisphere decreased with age. Moreover, exploratory analyses revealed a decrease in feedback-P3 amplitudes in response to monetary loss with increasing age. No other group differences were observed. Age-related changes in the SPN and fP3 component suggest that sensitivity to negative outcomes decreases from childhood to late adolescence, supporting the notion that adolescence is associated with reduced harm-avoidance. Longitudinal research including young adults is needed to substantiate our findings and its clinical implications regarding disturbed developmental trajectories in psychiatric populations.

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Dissociations between reading and spelling deficits are likely to be associated with distinct deficits in orthographic word processing. To specify differences in automatic visual word recognition, the current ERP-study compared children with isolated reading fluency deficits (iRD), isolated spelling deficits (iSD), and combined reading fluency and spelling deficits (cRSD) as well as typically developing (TD) 10-year-olds while performing a variant of the Reicher-Wheeler paradigm: children had to indicate which of two letters occurred at a given position in a previously presented word, legal pseudoword, illegal pseudoword or nonword. Event-related potentials (N200 and N400) associated with sublexical orthographic and lexical orthographic processing as well as phonological word processing were analyzed. All groups showed a word superiority effect, both on the behavioral and the neurophysiological level. Group differences occurred for phonological word processing. TD and iRD groups showed a higher N400 activation for illegal pseudowords than for nonwords, while the two spelling deficit groups showed no activation differences between these two stimuli conditions. The findings suggest that differences in phonological word processing are associated with spelling problems: children with iSD showed reduced sensitivity for phonological word processing, while these deficits were not evident in children with iRD.

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OBJECTIVE: Reading fluency deficits characteristic for reading disorders (RD; F81.0) have been shown to be strongly associated with slow naming speed (e.g. in rapid automatized naming tasks). In contrast, children with an isolated spelling disorder in the context of unimpaired reading skills (iSD; F81.1) show naming speed task performances that are similar to typically developing (TD) children. However, the exact nature of the naming speed deficit and its relation to RD and the question whether children with iSD are also on the neurophysiological level similar to TD children is still unresolved. METHODS: The time-course and scalp topography of event-related potentials (ERP) activity recorded during a delayed digit-naming task was investigated in ten-year-old children with RD and iSD compared to a TD group. RESULTS: ERP activity differed between the RD and the TD group at around 300 ms after stimulus presentation (left occipito-temporal P2). In contrast, there were no neurophysiological differences between the TD and the iSD group. The P2 component correlated with behavioural performance on the RAN task. CONCLUSIONS: Slow naming speed in RD might result from a slowed-down access and prolonged processing of the word (lexical) form. SIGNIFICANCE: The study establishes a relation between neurophysiological processes of naming tasks and RD.

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Dissociations between reading and spelling problems are likely to be associated with different underlying cognitive deficits, and with different deficits in orthographic learning. In order to understand these differences, the current study examined orthographic learning using a printed-word learning paradigm. Children (4th grade) with isolated reading, isolated spelling and combined reading and spelling problems were compared to children with age appropriate reading and spelling skills on their performance during learning novel words and symbols (non-verbal control condition), and during immediate and delayed reading and spelling recall tasks. No group differences occurred in the non-verbal control condition. In the verbal condition, initial learning was intact in all groups, but differences occurred during recall tasks. Children with reading fluency deficits showed slower reading times, while children with spelling deficits were less accurate, both in reading and spelling recall. Children with isolated spelling problems showed no difficulties in immediate spelling recall, but had problems in remembering the spellings 2 hours later. The results suggest that different orthographic learning deficits underlie reading fluency and spelling problems: Children with isolated reading fluency deficits have no difficulties in building-up orthographic representations, but access to these representations is slowed down while children with isolated spelling deficits have problems in storing precise orthographic representations in long-term memory.

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Efficient and automatic integration of letters and speech sounds is assumed to enable fluent word recognition and may in turn also underlie the build-up of high-quality orthographic representations, which are relevant for accurate spelling. While previous research showed that developmental dyslexia is associated with deficient letter-speech sound integration, these studies did not differentiate between subcomponents of literacy skills. In order to investigate whether deficient letter-speech sound integration is associated with deficits in reading and/or spelling, three groups of third graders were recruited: (1) children with combined deficits in reading and spelling (RSD, N = 10); (2) children with isolated spelling deficit (ISD, N = 17); and (3) typically developing children (TD, N = 21). We assessed the neural correlates (EEG) of letter-speech sound integration using a Stroop-like interference paradigm: participants had to decide whether two visually presented letters look identical. In case of non-identical letter pairs, conflict items were the same letter in lower and upper case (e.g., "T t"), while non-conflict items were different letters (e.g., "T k"). In terms of behavioral results, each of the three groups exhibited a comparable amount of conflict-related reaction time (RT) increase, which may be a sign for no general inhibitory deficits. Event-related potentials (ERPs), on the other hand, revealed group-based differences: the amplitudes of the centro-parietal conflict slow potential (cSP) were increased for conflicting items in typical readers as well as the ISD group. Preliminary results suggest that this effect was missing for children with RSD. The results suggest that deficits in automatized letter-speech sound associations are associated with reading deficit, but no impairment was observed in spelling deficit.

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OBJECTIVE: Event-related potential (ERP) studies have revealed abnormal neurophysiological patterns underlying selective attention in patients with Major Depression (MD). Only few included both patients in acute and remitted state to address the question whether these abnormalities are state- or trait- dependent and none focused on adolescent MD. Thus, the aim of our study was to address this question in an adolescent sample. METHODS: 22 adolescents with acute MD, 20 adolescents with remitted MD (rMD) and 32 healthy controls (HC) performed a standard two-tone auditory oddball task while ERPs (N100, P200, N200, P300) were collected. RESULTS: Adolescents with rMD showed a reduced N200 amplitude to target tones across frontal, central and parietal recording sites. Adolescents with MD exhibited a reduced N200 amplitude to targets in the frontal region compared to HC. No differences emerged between rMD and the MD group. CONCLUSIONS: The reduced N200 amplitude in adolescents with rMD and MD presumably reflects difficulties in stimulus classification and response selection. Our results indicate that this neurophysiological characteristic is a trait marker of adolescent depression.

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The brain's reward system undergoes major changes during adolescence, and an increased reactivity to social and nonsocial incentives has been described as a typical feature during this transitional period. Little is known whether there are sex differences in the brain's responsiveness to social or monetary incentives during adolescence. The aim of this event-related potential (ERP) study was to compare the neurophysiological underpinnings of monetary and social incentive processing in adolescent boys versus girls. During ERP recording, 38 adolescents (21 females, 17 males; 13-18 years) completed an incentive delay task comprising (a) a reward versus punishment condition and (b) social versus monetary incentives. The stimulus-preceding negativity (SPN) was recorded during anticipation of reward and punishment, and the feedback P3 (fP3) along with the feedback-related negativity (FRN) after reward/punishment delivery. During anticipation of social punishment, adolescent boys compared with girls exhibited a reduced SPN. After delivery, male adolescents exhibited higher fP3 amplitudes to monetary compared with social incentives, whereas fP3 amplitudes in girls were comparable across incentive types. Moreover, whereas in boys fP3 responses were higher in rewards than in punishment trials, no such difference was evident in girls. The results indicate that adolescent boys show a reduced neural responsivity in the prospect of social punishment. Moreover, the findings imply that, once the incentive is obtained, adolescent boys attribute a relatively enhanced motivational significance to monetary incentives and show a relative hyposensitivity to punishment. The findings might contribute to our understanding of sex-specific vulnerabilities to problem behaviors related to incentive processing during adolescence.

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OBJECTIVE: In consistent orthographies, isolated reading disorders (iRD) and isolated spelling disorders (iSD) are nearly as common as combined reading-spelling disorders (cRSD). However, the exact nature of the underlying word processing deficits in isolated versus combined literacy deficits are not well understood yet. METHODS: We applied a phonological lexical decision task (including words, pseudohomophones, legal and illegal pseudowords) during ERP recording to investigate the neurophysiological correlates of lexical and sublexical word-processing in children with iRD, iSD and cRSD compared to typically developing (TD) 9-year-olds. RESULTS: TD children showed enhanced early sensitivity (N170) for word material and for the violation of orthographic rules compared to the other groups. Lexical orthographic effects (higher LPC amplitude for words than for pseudohomophones) were the same in the TD and iRD groups, although processing took longer in children with iRD. In the iSD and cRSD groups, lexical orthographic effects were evident and stable over time only for correctly spelled words. CONCLUSIONS: Orthographic representations were intact in iRD children, but word processing took longer compared to TD. Children with spelling disorders had partly missing orthographic representations. SIGNIFICANCE: Our study is the first to specify the underlying neurophysiology of word processing deficits associated with isolated literacy deficits.

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The reading and spelling deficits characteristic of developmental dyslexia (dyslexia) have been related to problems in phonological processing and in learning associations between letters and speech-sounds. Even when children with dyslexia have learned the letters and their corresponding speech sounds, letter-speech sound associations might still be less automatized compared to children with age-adequate literacy skills. In order to examine automaticity in letter-speech sound associations and to overcome some of the disadvantages associated with the frequently used visual-auditory oddball paradigm, we developed a novel electrophysiological letter-speech sound interference paradigm. This letter-speech sound interference paradigm was applied in a group of 9-year-old children with dyslexia (n = 36) and a group of typically developing (TD) children of similar age (n = 37). Participants had to indicate whether two letters look visually the same. In the incongruent condition (e.g., the letter pair A-a) there was a conflict between the visual information and the automatically activated phonological information; although the visual appearance of the two letters is different, they are both associated with the same speech sound. This conflict resulted in slower response times (RTs) in the incongruent than in the congruent (e.g., the letter pair A-e) condition. Furthermore, in the TD control group, the conflict resulted in fast and strong event-related potential (ERP) effects reflected in less negative N1 amplitudes and more positive conflict slow potentials (cSP) in the incongruent than in the congruent condition. However, the dyslexic group did not show any conflict-related ERP effects, implying that letter-speech sound associations are less automatized in this group. Furthermore, we examined general visual conflict processing in a control visual interference task, using false fonts. The conflict in this experiment was based purely on the visual similarity of the presented objects. Visual conflict resulted in slower RTs, less negative N2 amplitudes and more positive cSP in both groups. Thus, on a general, basic level, visual conflict processing does not seem to be affected in children with dyslexia.

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To date, little is known about sex differences in the neurophysiological correlates underlying auditory information processing. In the present study, auditory evoked potentials were evoked in typically developing male (n = 15) and female (n = 14) adolescents (13-18 years) during an auditory oddball task. Girls compared to boys displayed lower N100 and P300 amplitudes to targets. Larger N100 amplitudes in adolescent boys might indicate higher neural sensitivity to changes of incoming auditory information. The P300 findings point toward sex differences in auditory working memory and might suggest that adolescent boys might allocate more attentional resources when processing relevant auditory stimuli than adolescent girls.

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Targets in a visual search task are detected faster if they appear in a probable target region as compared to a less probable target region, an effect which has been termed "probability cueing." The present study investigated whether probability cueing cannot only speed up target detection, but also minimize distraction by distractors in probable distractor regions as compared to distractors in less probable distractor regions. To this end, three visual search experiments with a salient, but task-irrelevant, distractor ("additional singleton") were conducted. Experiment 1 demonstrated that observers can utilize uneven spatial distractor distributions to selectively reduce interference by distractors in frequent distractor regions as compared to distractors in rare distractor regions. Experiments 2 and 3 showed that intertrial facilitation, i.e., distractor position repetitions, and statistical learning (independent of distractor position repetitions) both contribute to the probability cueing effect for distractor locations. Taken together, the present results demonstrate that probability cueing of distractor locations has the potential to serve as a strong attentional cue for the shielding of likely distractor locations.