Auditory rhythm facilitates perception and action in children at risk for developmental coordination disorder.

Developmental Coordination Disorder (DCD) is a common neurodevelopmental disorder featuring deficits in motor coordination and motor timing among children. Deficits in rhythmic tracking, including perceptually tracking and synchronizing action with auditory rhythms, have been studied in a wide range of motor disorders, providing a foundation for developing rehabilitation programs incorporating auditory rhythms. We tested whether DCD also features these auditory-motor deficits among 7-10 year-old children. In a speech recognition task with no overt motor component, modulating the speech rhythm interfered more with the performance of children at risk for DCD than typically developing (TD) children. A set of auditory-motor tapping tasks further showed that, although children at risk for DCD performed worse than TD children in general, the presence of an auditory rhythmic cue (isochronous metronome or music) facilitated the temporal consistency of tapping. Finally, accuracy in the recognition of rhythmically modulated speech and tapping consistency correlated with performance on the standardized motor assessment. Together, the results show auditory rhythmic regularity benefits auditory perception and auditory-motor coordination in children at risk for DCD. This provides a foundation for future clinical studies to develop evidence-based interventions involving auditory-motor rhythmic coordination for children with DCD.

Managing an intentional overdose in a hospice.

This case report describes a patient admitted unconscious to a hospice following an intentional overdose of oxycodone. She had previously declined conventional medical treatment for cancer and had made an advance decision stating that she wished to avoid hospital admission and refusing life-prolonging treatment. This case illustrates the practical and ethical challenges of managing an intentional overdose in a palliative care setting.

Time-limited modulation of appetitive Pavlovian memory by D1 and NMDA receptors in the nucleus accumbens.

Recent research has implicated the nucleus accumbens (NAc) in consolidating recently acquired goal-directed appetitive memories, including spatial learning and other instrumental processes. However, an important but unresolved issue is whether this forebrain structure also contributes to the consolidation of fundamental forms of appetitive learning acquired by Pavlovian associative processes. In addition, although dopaminergic and glutamatergic influences in the NAc have been implicated in instrumental learning, it is unclear whether similar mechanisms operate during Pavlovian conditioning. To evaluate these issues, the effects of posttraining intra-NAc infusions of D1, D2, and NMDA receptor antagonists, as well as d-amphetamine, were determined on Pavlovian autoshaping in rats, which assesses learning by discriminated approach behavior to a visual conditioned stimulus predictive of food reward. Intracerebral infusions were given either immediately after each conditioning session to disrupt early memory consolidation or after a delay of 24 h. Findings indicate that immediate, but not delayed, infusions of both D1 (SCH 23390) and NMDA (AP-5) receptor antagonists significantly impair learning on this task. By contrast, amphetamine and the D2 receptor antagonist sulpiride were without significant effect. These findings provide the most direct demonstration to date that D1 and NMDA receptors in the NAc contribute to, and are necessary for, the early consolidation of appetitive Pavlovian learning.