Parahippocampal cortex is involved in material processing via echoes in blind echolocation experts

Some blind humans use sound to navigate by emitting mouth-clicks and listening to the echoes that reflect from silent objects and surfaces in their surroundings. These echoes contain information about the size, shape, location, and material properties of objects. Here we present results from an fMRI experiment that investigated the neural activity underlying the processing of materials through echolocation. Three blind echolocation experts (as well as three blind and three sighted non-echolocating control participants) took part in the experiment. First, we made binaural sound recordings in the ears of each echolocator while he produced clicks in the presence of one of three different materials (fleece, synthetic foliage, or whiteboard), or while he made clicks in an empty room. During fMRI scanning these recordings were played back to participants. Remarkably, all participants were able to identify each of the three materials reliably, as well as the empty room. Furthermore, a whole brain analysis, in which we isolated the processing of just the reflected echoes, revealed a material-related increase in BOLD activation in a region of left parahippocampal cortex in the echolocating participants, but not in the blind or sighted control participants. Our results, in combination with previous findings about brain areas involved in material processing, are consistent with the idea that material processing by means of echolocation relies on a multi-modal material processing area in parahippocampal cortex

Shape-specific activation of occipital cortex in an early blind echolocation expert

We have previously reported that an early-blind echolocating individual (EB) showed robust occipital activation when he identified distant, silent objects based on echoes from his tongue clicks (Thaler, Arnott, & Goodale, 2011). In the present study we investigated the extent to which echolocation activation in EB's occipital cortex reflected general echolocation processing per se versus feature-specific processing. In the first experiment, echolocation audio sessions were captured with in-ear microphones in an anechoic chamber or hallway alcove as EB produced tongue clicks in front of a concave or flat object covered in aluminum foil or a cotton towel. All eight echolocation sessions (2 shapes×2 surface materials×2 environments) were then randomly presented to him during a sparse-temporal scanning fMRI session. While fMRI contrasts of chamber versus alcove-recorded echolocation stimuli underscored the importance of auditory cortex for extracting echo information, main task comparisons demonstrated a prominent role of occipital cortex in shape-specific echo processing in a manner consistent with latent, multisensory cortical specialization. Specifically, relative to surface composition judgments, shape judgments elicited greater BOLD activity in ventrolateral occipital areas and bilateral occipital pole. A second echolocation experiment involving shape judgments of objects located 20° to the left or right of straight ahead activated more rostral areas of EB's calcarine cortex relative to location judgments of those same objects and, as we previously reported, such calcarine activity was largest when the object was located in contralateral hemispace. Interestingly, other echolocating experts (i.e., a congenitally blind individual in Experiment 1, and a late blind individual in Experiment 2) did not show the same pattern of feature-specific echo-processing calcarine activity as EB, suggesting the possible significance of early visual experience and early echolocation training. Together, our findings indicate that the echolocation activation in EB's occipital cortex is feature-specific, and that these object representations appear to be organized in a topographic manner

Methods of evaluation of thermal tolerance of cyclic sports athletes

The purpose of the study is investigation of thermal stability in athletes of cyclic sports and assessment of its influence on physical working capacity under hyperthermia. Material and methods. 15 male athletes of cyclic sports who had the senior degree as minimum were included in the study Middle age 24,2±1,1 years. Work was performed in the climatic camera of the Center of sports medicine and rehabilitation in several stages, on each of which assessment of physical working capacity and a thermal condition of athletes was carried out. Results. In the real work the burdening action of the heating climate on indicators of physical working capacity and a thermal condition of athletes of cyclic sports is shown; the operating ranges of high temperatures are determined. Conclusion. The data obtained by means of the offered technique, confirm importance of definition of individual thresholds of shipping of a thermal state at athletes and the burdening action of a heat on their physical working capacity.</p

Comparative estimation of metrological characteristics of different PCR types for quantitative material assessment in complex matrices on the example of soybeans’ GM line

A method of quantitative determination of genetically modified line (GM line) of soybean Mon 89788 based on digital PCR has been developed. Comparative analysis of metrological characteristics of this technique with identical based on PCR-RT was carried out. Both the detection limit and the quantitative detection limit of the methodology were defined. Correlation coefficient (R2=0.9987) was close to the maximum value, indicating a good correlation of the analytical signal linear dependence of the GMO content in the panel samples. The digital PCR methodology allows to determine the GMO content in the range from 0.5% to 100%. Compared to real time PCR results, digital PCR results show GMO content closer to the reference value; however, this technique does not allow to determine GMO content below 0.5%

Evaluation of the effect of a special cooling liquid on thermal state of athletes at high temperatures

Aim. The article presents the results of the effectiveness of cooling liquid. In addition, the way it affects the thermal state of athletes at high temperatures. Material and Methods. The study involved seven male athletes of cyclic sports. The sportsmen had a senior or higher and an average age of 19.29±1.80 years. All passed a 2-fold examination, which included collection of anamnesis, complaints about health, medical examination, weight measurement, subjective evaluation of heat thermometry (rectal and skin (in 5 points)), ergospirometry testing. Changing the thermal state of the athletes, founded by the dynamics of average skin temperature and rectal temperature. Also, subjective evaluation of thermal sensations was taken into account. Meanwhile the efficiency of special cooling liquid determined by the dynamic run-time load, maximal oxygen uptake and anaerobic threshold of exchange. Results. The use of special cooling liquid makes it possible to increase the time of aerobic load tolerance in conditions of high temperatures by an average of 2.5%. This was accompanied by a decrease in rectal temperature and average skin temperature throughout the stress test. There is also a positive effect on the subjective level of heat sensations. Conclusions. We conclude that it is advisable to use cooling liquid for summer sports teams in the performance of a specific physical activity. However first conducted individual tests on the subject of possible adverse allergic reactions.</p