This study assessed the effect of stimulating the somatosensory system of Alzheimer's disease (AD) patients at three stages of their illness with 40 Hz sound. In this AB cross-over study design, 18 participants (6 mild, 6 moderate, 6 severe) each participated in 13 sessions: one intake and 12 treatment. Treatment A consisted of 40 Hz sound stimulation and Treatment B consisted of visual stimulation using DVDs, each provided twice a week over 6 weeks for a total of 6 times per treatment. Outcome measures included: St. Louis University Mental Status Test (SLUMS), Observed Emotion Rating Scale, and behavioral observation by the researcher. Data were submitted to regression analysis for the series of 6 SLUMS scores in treatment A and 6 scores in B with comparison by group. The slopes for the full sample and subgroups in the 40 Hz treatment were all significant beyond alpha = 0.05, while those for the DVD were not. A thematic analysis of qualitative observations supported the statistical findings. 40 Hz treatment appeared to have the strongest impact on persons with mild and moderate AD. Results are promising in terms of a potential new treatment for persons with AD, and further research is needed.

Loss of sharks and other upper-trophic marine predators has sparked worldwide concern for the stability of ocean ecosystems. The grey nurse (ragged-tooth or sand tiger) shark (Carcharias taurus) is Vulnerable on a global scale, Critically Endangered in Australia and presumed extinct in parts of its historical range. We used 193 muscle and fin samples collected from six extant populations to assess global mtDNA and microsatellite diversity and the degree of global population genetic structure. Control region mtDNA diversity was low in every population, and two populations (eastern Australia and Japan) contained only a single mtDNA haplotype. Genetic signatures of recent losses of genetic variation were not yet apparent at microsatellite loci, indicating that this low mtDNA variation is not a result of anthropogenic population declines. Population differentiation was substantial between each population pair except Brazil and South Africa, F(ST) values ranged from 0.050 to 0.699 and 0.100 to 1.00 for microsatellite and mitochondrial data respectively. Bayesian analysis clearly partitioned individuals into five of the populations from which they were sampled. Our data imply a low frequency of immigrant exchange among each of these regions and we suggest that each be recognized as a distinct evolutionary significant unit. In contrast to pelagic species such as whale shark and white shark that may cross ocean basins and where cooperative international efforts are necessary for conservation, grey nurse shark, like many coastal species, need to be managed regionally.

Recent studies have suggested that vibration therapy may have a positive influence on motor symptoms in individuals with Parkinson's disease (PD). However, quantitative evidence of these benefits is scarce, and the concept of "whole-body" vibration in these studies is vague. The objectives of the current study were to evaluate the influence of vibration on motor symptoms and functional measures in PD by delivering sound waves to the entire body. We delivered whole body sound wave vibration to 40 individuals with PD using a Physioacoustic Chair, a piece of equipment with speakers spaced throughout the chair permitting a series of programmed low frequency sound waves through the body. Using a parallel cross-over design we utilized the Unified Parkinson's Disease Rating Scale (UPDRS), quantitative gait assessments, and a grooved pegboard for upper limb control. Improvements were seen in all symptom, motor control and functional outcome measures at the time of assessment. Specifically, a significant decrease in rigidity, and tremor were shown, as well as a significant increase in step length and improved speed on the grooved pegboard task. Results of this initial investigation provide support for vibration therapy as a non-pharmacological treatment alternative. Long-term benefits of vibration therapy will require further research.

Researchers have hypothesized that thalamocortical dysfunction plays a role in fibromyalgia. The use of low-frequency sound stimulation to ameliorate thalamocortical dysfunction has also been investigated, and has shown promise in treating certain pain conditions. Accordingly, the authors of this study aimed to assess the effects of treatment with low-frequency sound stimulation among patients with fibromyalgia.

The Arctic is experiencing rapid warming, and resultant sea ice losses represent a serious threat to ice-associated species in the region. This study explored the distribution and abundance of the 3 Arctic resident whale species: narwhals, bowhead and white whales, in the marginal ice zone and into the sea ice north of the Svalbard Archipelago. Line-transect surveys were conducted using a combination of helicopter-based and ship-based efforts in August 2015. Twenty-six sightings, involving 27 bowhead whales and 58 narwhals, occurred along the helicopter transects, while no whales were recorded along ship transects. No white whales were observed during these surveys. After correcting for surface availability, distance sampling produced abundance estimates of 343 (CV = 0.488) bowhead whales and 837 (CV = 0.501) narwhals within the 52 919 km 2 study area. Bowhead whales were predominantly seen close to the ice-edge, whereas narwhals were located deeper into the ice. To contextualize these results within the broader Svalbard cetacean community, all whale sightings from the Norwegian Polar Institute's Svalbard Marine Mammal Sighting Data Base, from the period of the survey, were mapped to compare general distributions. These opportunistic sightings included numerous cetacean species, especially seasonally occurring ones. However, white whales dominated in terms of the numbers of individuals reported. Our results suggest little spatial overlap between seasonally occurring whales and the 3 Arctic resident whales. Bowhead whales and narwhals were tightly associated with sea ice, and white whales were tightly coastal. In contrast, the seasonally occurring species were found over the shelf and along its edges.

No abstract

To better understand fin whale vocalization behaviour in the Norwegian and Barents Seas, a large-aperture densely sampled coherent hydrophone array was deployed in late winter 2014 to monitor their vocalizations instantaneously over wide areas via passive ocean acoustic waveguide remote sensing (POAWRS). Here, we (i) provide a time-frequency characterization for different call types observed (20 Hz pulses, 130 Hz upsweeps, 30–100 Hz downsweep chirps, and 18–19 Hz backbeats); (ii) compare their relative abundances in three different coastal regions off Alesund, Lofoten, and Northern Finnmark; (iii) estimate the temporal and spatial distributions; (iv) source level distributions; and (v) probability of detection (PoD) regions for the more abundant 20 Hz pulse and 130 Hz upsweep call types. The fin whale vocalizations received over the diel cycle (24 h) were significantly more abundant by a factor of roughly seven off Northern Finnmark than the other two regions, associated with fish feeding activities. The source levels are estimated to be 190.5±7.4 dB for the fin whale 20 Hz pulses and 170.3 ± 5.2 dB for the 130 Hz upsweeps. We find that fin whales are capable of producing each vocalization type either independently or simultaneously with other types, and the 20 Hz sound production in the fin whales involves a mechanism that generates a significantly less-intense second-order harmonic of the fundamental.

In pinnipeds, maternal care strategies and colony density may influence a species' individual recognition system. We examined the onset of vocal recognition of mothers by Australian sea lion pups (Neophoca cinerea). At 2 months of age, pups responded significantly more to the calls of their own mothers than alien female calls demonstrating a finely tuned recognition system. However, newborn pups did not respond differentially to the calls of their mother from alien female calls suggesting that vocal recognition had not yet developed or is not yet expressed. These findings are in stark contrast to other otariid species where pups learn their mother's voice before their first separation. Variance in colony density, pup movements, and natal site fidelity may have reduced selective pressures on call recognition in young sea lions, or alternatively, another sensory system may be used for recognition in the early stage of life.