The role of perceived source location in auditory stream segregation: separation affects sound organization, common fate does not

The human auditory system is capable of grouping sounds originating from different sound sources into coherent auditory streams, a process termed auditory stream segregation. Several cues can influence auditory stream segregation, but the full set of cues and the way in which they are integrated is still unknown. In the current study, we tested whether auditory motion can serve as a cue for segregating sequences of tones. Our hypothesis was that, following the principle of common fate, sounds emitted by sources moving together in space along similar trajectories will be more likely to be grouped into a single auditory stream, while sounds emitted by independently moving sources will more often be heard as two streams. Stimuli were derived from sound recordings in which the sound source motion was induced by walking humans. Although the results showed a clear effect of spatial separation, auditory motion had a negligible influence on stream segregation. Hence, auditory motion may not be used as a primitive cue in auditory stream segregation

Attention and speech-processing related functional brain networks activated in a multi-speaker environment

Human listeners can focus on one speech stream out of several concurrent ones. The present study aimed to assess the whole-brain functional networks underlying a) the process of focusing attention on a single speech stream vs. dividing attention between two streams and 2) speech processing on different time-scales and depth. Two spoken narratives were presented simultaneously while listeners were instructed to a) track and memorize the contents of a speech stream and b) detect the presence of numerals or syntactic violations in the same (“focused attended condition”) or in the parallel stream (“divided attended condition”). Speech content tracking was found to be associated with stronger connectivity in lower frequency bands (delta band- 0,5–4 Hz), whereas the detection tasks were linked with networks operating in the faster alpha (8–10 Hz) and beta (13–30 Hz) bands. These results suggest that the oscillation frequencies of the dominant brain networks during speech processing may be related to the duration of the time window within which information is integrated. We also found that focusing attention on a single speaker compared to dividing attention between two concurrent speakers was predominantly associated with connections involving the frontal cortices in the delta (0.5–4 Hz), alpha (8–10 Hz), and beta bands (13–30 Hz), whereas dividing attention between two parallel speech streams was linked with stronger connectivity involving the parietal cortices in the delta and beta frequency bands. Overall, connections strengthened by focused attention may reflect control over information selection, whereas connections strengthened by divided attention may reflect the need for maintaining two streams in parallel and the related control processes necessary for performing the tasks.</div

Genetic characterization of an H2N2 influenza virus isolated from a muskrat in Western Siberia

Thirty-two muskrats (Ondatra zibethicus) were captured for surveillance of avian influenza virus in wild waterfowl and mammals near Lake Chany, Western Siberia, Russia. A/muskrat/Russia/63/2014 (H2N2) was isolated from an apparently healthy muskrat using chicken embryos. Based on phylogenetic analysis, the hemagglutinin and neuraminidase genes of this isolate were classified into the Eurasian avian-like influenza virus clade and closely related to low pathogenic avian influenza viruses (LPAIVs) isolated from wild water birds in Italy and Sweden, respectively. Other internal genes were also closely related to LPAIVs isolated from Eurasian wild water birds. Results suggest that interspecies transmission of LPAIVs from wild water birds to semiaquatic mammals occurs, facilitating the spread and evolution of LPAIVs in wetland areas of Western Siberia

THE ISOLATION OF INFLUENZA A VIRUS FROM PLUMAGE OF WATERFOWL DURING AUTUMN MIGRATION

Aim. In the present work we investigated the circulation of AIV in wild bird populations and studied the sorption of the influenza virus in the feathers of wild waterfowl nesting on reservoirs during the autumn mass migration. Material and methods. Sampling was carried out on the territory of the Novosibirsk region on Lake Chany during the period from August to September 2014-2016. Biological samples were collected from 188 wild waterfowl of various species. AIV isolation from cloacal swabs and swabs collected from feathers was carried out in the developing chick embryo system (RCC) as previously recommended. The isolated viruses were tested by HA/HI with specific sera, PCR analysis was carried out with subtyping primers. The genomes of the isolated viruses were sequenced for phylogenetic analysis. Results and discussion. As a result of monitoring, cloacal and feather swabs were collected from 188 individuals belonging to 13 species of the Anseriformes and Charadriiformes, whose representatives are the main natural reservoir of AIV. Fifteen new AI viruses were isolated from the collected samples. Four of them were isolated from plumage samples and the rate was more than 2 times lower, compared with virus isolation from cloacal swabs. Main conclusions. Thus, it can be assumed that avian influenza virus transmission by plumage during migration is not sufficiently taken into account. The key role in AIV ecology may play the virus spreading by its adsorption on bird feathers

Demonstration #8: Synchrony test (in phase)

<p>Demonstration #8: Synchrony test (in phase)<br>Length: 0:20 </p

Demonstration #4: 2 balls standing (2.67Hz)

<p>Demonstration #4: 2 balls standing (2.67Hz)<br>Length: 0:20 </p

Stimulus: Incongruent/Moving/Joint

<p>Stimulus: Incongruent/Moving/Joint<br>Length: 4:05 </p

Demonstration #3: 1 ball standing (2Hz)

<p>Demonstration #3: 1 ball standing (2Hz)<br>Length: 0:20 </p

Demonstration #9: Synchrony test (out of phase)

<p>Demonstration #9: Synchrony test (out of phase)<br>Length: 0:20 </p

Demonstration #5: 2 balls standing (8Hz)

<p>Demonstration #5: 2 balls standing (8Hz)<br>Length: 0:20 </p