The Value of Measuring Impact Alongside Symptoms in Children and Adolescents: A Longitudinal Assessment in a Community Sample

The impact that psychiatric symptoms have on the lives of young people is central to clinical practice and classification. However, there is relatively little research on impact and its association with symptoms. This paper examines how well impact can be measured and how it relates to psychiatric outcomes. On four separate occasions over 3 years, symptoms and impact were assessed in a UK epidemiological sample (n?=?4,479; 51.5 % boys) using the Strengths and Difficulties Questionnaire (SDQ) as reported by parents, youths and teachers. Disorders were ascertained using the Development and Well-Being Assessment. An impact scale made of items about distress and impairment demonstrated considerable internal consistency, cross-informant correlations, and longitudinal stability by all reporting sources. Impact at baseline was a strong predictor of psychiatric disorder 3 years later after accounting for psychiatric disorders and symptoms measured at baseline: odds ratio OR?=?2.10, 95 % Confidence Interval (CI) [1.50, 2.94] according to parent-rated impact and OR?=?1.71, CI [1.08, 2.72] according to teacher-rated impact. Changes in impact over time were predicted, but not fully accounted for, by symptoms measured at baseline. Impact can be reliably and easily measured across time, and it may be clinically useful as an independent predictor of future symptoms and psychiatric disorders. More studies are needed to understand inter-individual variation in the impact caused by equivalent symptoms.     

Family and Cultural Predictors of Depression Among Samoan American Middle and High School Students

This study investigated family intergenerational conflict and collective self‐esteem as predictors of depression in a sample of 128 Samoan middle and high school students. Simultaneous regression analyses revealed that each independent variable significantly contributed to an overall model that accounted for 13% of the variance in depression. Implications for counseling research and practice are discussed in terms of how schools may consider ways to promote these youth's cultural worth and positive family dynamics. Este estudio investigó el conflicto familiar intergeneracional y la autoestima colectiva como predictores de depresión en una muestra de 128 estudiantes samoanos de enseñanza media y secundaria. Los análisis simultáneos de regresión revelaron que cada variable independiente contribuyó de forma significativa a un modelo general que explicó un 13% de la varianza en depresión. Se discuten las implicaciones para la investigación y práctica de la consejería, en términos de cómo las escuelas pueden considerar formas de promover el valor cultural de estos jóvenes y una dinámica familiar positiva.     

On the space-time structure of human interlimb co-ordination

In three experiments we show, using behavioural measures of movement outcome, as well as movement trajectory information and resultant kinematic profiles, that there is a strong tendency for the limbs to be co-ordinated as a unitary structure even under conditions where the movements are of disparate difficulty. Environmental constraints (an obstacle placed in the path of one limb, but not in the other) are shown to modulate the space-time behaviour of both limbs (Experiment II). Our results obtain for symmetrical (Experiment I) as well as asymmetrical movements that involve non-homologous muscle groups (Experiment III). These findings suggest that in multi-joint limb movements, the many degrees of freedom are organised to function temporarily as a single coherent unit that is uniquely specific to the task demands placed on it. For movements in general, and two-handed movements in particular, such units are revealed in a partitioning of the relevant force demands for each component (a force scaling characteristic) and a preservation of the internal “topology” of the action, as indexed by the relative timing among components. These features, as well as systematic deviations from perfect synchrony between the limbs can be rationalised by a model that assumes the limbs behave qualitatively like non-linear oscillators.     

The Effect of Practice on the Control of Rapid Aiming Movements: Evidence for an Interdependency Between Programming and Feedback Processing

The purpose of this experiment was to investigate how the control of aiming movements performed as fast and as accurately as possible changes with practice. We examined: (1) the influence of visual feedback on the initial impulse and error correction phases of aiming movements during acquisition; and (2) the effect of removing visual feedback at different levels of practice. Results from the acquisition trials indicated that vision had a major impact on the organization of the initial impulse and error correction phases. Also, consistent with findings from research involving temporally constrained movements, the cost of removing vision was greater after extensive levels than after moderate levels of practice. Collectively, these results denote the importance of visual feedback to the learning of this particular class of aiming movements. Learning appears to be a dual process of improved programming of the initial impulse and increased efficiency of feedback processing. Practice not only acts on programming and feedback processes directly, but also indirectly through a reciprocal interplay between these two processes.     

Submerged electrodes in an aquarium: Validation of a technique for remote sensing of behavior

Necturus maculosus has been selected as representative of a class of neotenic amphibia whose behavior (including gill beat, heartbeat, and tail waving) can be sensed remotely by submerged electrodes in an aquarium. This communication presents a validation of the technique as a preface to reports on the electrophysiology of behavior in unrestrained surgically naive salamanders. Although the sources of the submarine signals are not known with certainty, they apparently depend on two factors: (1) aquarium water of appropriate ionic strength serves as a volume conductor for activity, and (2) animal movement displaces water or produces waves which are sensed as a change in potential at the water-electrode interface. This method provides a continuous comprehensive record of behavior simultaneously from several response systems in a freely behaving animal.