Temperament and attention-deficit/hyperactivity disorder (ADHD) are both typically viewed as biologically based behavioural constructs. There is substantial overlap between ADHD symptoms and specific temperamental traits, such as effortful control, especially in young children. Recent work by Martel and colleagues ( 2009 , 2011 ) suggests that cognitive control temperamental processes are more closely related to inattention symptoms, whereas stimulus-driven temperamental processes are linked to hyperactivity-impulsivity. The present study tested a model of temperament and ADHD symptoms in typically developing preschoolers and those at risk for ADHD using structural equation modelling. Data were from larger study on ADHD in a short-term longitudinal sample with parent/teacher reports and neurocognitive testing. Participants included 214 preschool children (72.9% male) from diverse ethnic/racial backgrounds and a wide range of socioeconomic status from a large metropolitan center. Cognitive control processes, such as effortful control, but not stimulus-driven processes, are related to inattention and hyperactivity. In contrast, stimulus-driven processes, such as emotional reactivity, were related only to hyperactivity symptoms longitudinally. These results suggest that early temperament behaviours and cognitive processes may be indicators of later childhood behavioural difficulties with lasting consequences.

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Objective: The dual-specificity phosphatase 6 (DUSP6) gene resides at chromosome location 12q22-23, which is one of the candidate loci for susceptibility to bipolar disorder and which encodes a phosphatase selective for extracellular signal-regulated kinase (ERK). In this study, we investigated the genetic association between DUSP6 gene and BD, and also investigated the functions of the Leu114Val and Ser144Ala mutations in DUSP6 proteins, which were raised by T/G polymorphisms in exon 1 and exon 2, respectively.Methods: This study investigated the genetic association of DUSP6 with BD and schizophrenia (SPR) in the Korean population. Based on the evidence of the sexdimorphic effect of DUSP6 on BD, we performed two independent analyses in homogeneous samples of female and male patients. Moreover, the effects of missense mutations in the Leu114Val and Ser144Ala of DUSP6 proteins associated with T/G polymorphisms in exons 1 and 2, which showed positive associations with BD in this study, were also investigated in terms of their activation of ERK1/2 in response to lithium treatment. A. Diez-Revuelta, C. Tobon, J.M. Porto, M.V. Perea, V. Molina, R. Hornero and M. Franco-Martin Objective: Several lines of research currently support the existence of disorganized activity patterns in schizophrenia. Electroencephalogram (EEG) studies can help understand the possible implication of such disruption for cognitive deficits shown by patients with schizophrenia.