No abstract

Aggression observed in 2-year-old children of well and depressed mothers was examined in relation to problem behaviors at ages 5–6. Both normative (e.g., object struggles, rough play) and maladaptive (e.g., dysregulated, out-of-control behavior) forms of toddler aggression were identified. Dysregulated aggression predicted (a) externalizing problems reported by mothers when children were 5 years old, and (b) children's reports of difficulties during a structured psychiatric interview at age 6. Problems were more frequent and continuity patterns more evident in children of depressed, than well, mothers. Early maladaptive aggression was a better predictor of later externalizing, than internalizing problems. Childrearing practices of mothers of toddlers also appeared to contribute to later outcomes: negative influences were evident but protective patterns were present as well. Depressed mothers who used proactive childrearing approaches (e.g., anticipating the child's point of view; exerting modulated, respectful control; providing structure and organization during play environment) had children who showed fewer externalizing problems 3 years later.

The auditory system continuously parses the acoustic environment into auditory objects, usually representing separate sound sources. Sound sources typically show characteristic emission patterns. These regular temporal sound patterns are possible cues for distinguishing sound sources. The present study was designed to test whether regular patterns are used as cues for source distinction and to specify the role that detecting these regularities may play in the process of auditory stream segregation. Participants were presented with tone sequences, and they were asked to continuously indicate whether they perceived the tones in terms of a single coherent sequence of sounds (integrated) or as two concurrent sound streams (segregated). Unknown to the participant, in some stimulus conditions, regular patterns were present in one or both putative streams. In all stimulus conditions, participants' perception switched back and forth between the two sound organizations. Importantly, regular patterns occurring in either one or both streams prolonged the mean duration of two-stream percepts, whereas the duration of one-stream percepts was unaffected. These results suggest that temporal regularities are utilized in auditory scene analysis. It appears that the role of this cue lies in stabilizing streams once they have been formed on the basis of simpler acoustic cues.

No abstract

Auditory stream segregation involves linking temporally separate acoustic events into one or more coherent sequences. For any non-trivial sequence of sounds, many alternative descriptions can be formed, only one or very few of which emerge in awareness at any time. Evidence from studies showing bi-/multistability in auditory streaming suggest that some, perhaps many of the alternative descriptions are represented in the brain in parallel and that they continuously vie for conscious perception. Here, based on a predictive coding view, we consider the nature of these sound representations and how they compete with each other. Predictive processing helps to maintain perceptual stability by signalling the continuation of previously established patterns as well as the emergence of new sound sources. It also provides a measure of how well each of the competing representations describes the current acoustic scene. This account of auditory stream segregation has been tested on perceptual data obtained in the auditory streaming paradigm.