The role of attention and explicit knowledge in perceiving bistable auditory input.

The auditory system frequently encounters ambiguous sound input that can be perceived in multiple ways. The current study investigated the role of explicit knowledge in modulating how sounds are represented in auditory memory for a bistable sound sequence that could be perceived equally as integrated or segregated. We hypothesized that the dominant percept of the bistable sequence would suppress representation of the alternative perceptual organization as a function of how much top-down knowledge the listener had about the structure of the sequence.

Cognitive resources are distributed among the entire auditory landscape in auditory scene analysis.

Although attention has been shown to enhance neural representations of selected inputs, the fate of unselected background sounds is still debated. The goal of the current study was to understand how processing resources are distributed among attended and unattended sounds during auditory scene analysis. We used a three-stream paradigm with four acoustic features uniquely defining each sound stream (frequency, envelope shape, spatial location, tone quality).

Childhood leukemia survivors exhibit deficiencies in sensory and cognitive processes, as reflected by event-related brain potentials after completion of curative chemotherapy: A preliminary investigation.

: The purpose of this study was to characterize post-chemotherapy sensory, memory, and attention abilities in childhood survivors of acute lymphoblastic leukemia (ALL) to better understand how treatment affects cognitive functioning. : Eight ALL survivors and eight age-matched, healthy children between the ages of 5-11 years participated in the study. Among the ALL survivors, a median of 63 days (range 22-267 days) elapsed between completion of chemotherapy and this assessment.

Synthesis of 2'-deoxy-9-deaza nucleosides using Heck methodology.

During the synthesis of a series of 2'-deoxy-9-deaza nucleosides using Heck methodology, the necessity for a pyrrole protecting group was discovered. The results of this brief study revealed that the benzyloxymethyl (BOM) group proved optimal, and Heck coupling using Jeffery conditions increased the coupling yield significantly. The results are reported herein.