They watch videos on YouTube age appropriate , they play video games on Xbox and talk to their friends across town using Xbox Live and employ multi-play functions so that they are all involved in the same game. These kids are embracing technology as quickly as it comes out — they are connected. A quick little aside in addition to the above: my wife and I were outside of our house earlier this spring and both commented on how ugly the cable wires that run along the house were. We traced the wires back to the box and saw that several of the wires were connected to a box that belongs to a different cable company than our service provider…so out came the wire cutters.
We removed probably about feet of unnecessary cable wire — or so we thought. The good news is that the largest TV screen in the house still gets a cable feed and that the internet cable connection are both still in tact. But we killed the connection to the other two spots in the house. The kids complained for about a week. I mention this story to also point out that: in addition to being well connected, this next generation does not want to be hit upside the head with a mass advertisement. One size no longer fits all.
With all of the above in mind, here are some staggering statistics for you: the USPS did a recent study of how many media messages the average consumer is bombarded with every single day. That number is 2, media messages.
Every day. The number of messages that are paid attention to: 52 out of 2, or 1. The number of media messages that are remembered favorably: four. Out of 2, messages, only 0. How do YOU stand out in that very crowded space? Good old, traditional printing — ink on paper — at one point not all that long ago — relatively speaking was the preferred read: only medium for how any company that wanted to get their word out about themselves that was utilized.
Blurred lines and job titles
Along came radio, then TV, then the internet, then mobile devices, then tablets, then social media. These were all disruptive, game-changing technologies. Advertising spend and budgets still include radio and TV and of course internet and even print. Just think of other applications that exist for this. Want to see what granite countertops would look like in your kitchen? Or how about ju st some business cards that utilize AR technology to show an introductory video of you and your company that links up to your interactive web-site. Want proof? I showed my 16 year old some already existing AR apps on my phone last night when I got home.
How about a cool application using NFC tags? In all three species, the median population latency of the subgroup of neurons that were responsive to the specific echo delays increased gradually with the studied echo delay, yielding correlation coefficients above 0. The number of neurons activated by a specific echo delay value is indicated above the graphs.
Horizontal lines inside the boxes indicate median population latencies and the whiskers extend to the most extreme data points not considered outliers. The linear correlation coefficient R calculated between the different echo delays and median population latencies is given. The median RD is represented by the horizontal line inside the boxes. Note that in all three species, responses to echo delays that are more similar are more likely to occur simultaneously in the cortex.
There was certain variability in the population latencies to the different echo delays. Such variability was quantified by measuring the quartiles 25th and 75th percentiles of population latencies distributions that is, represented by the boxes in Fig. This parameter was denoted as the minimum population latency MinPL.
On the other hand, the 75th percentile upper edge in the boxplots is a measure of maximum population latencies MaxPLs. Together with the median response duration RD represented in Fig. Intervals of concurrent activation ICA were calculated to determine the extent to which responses to different echo delays could occur simultaneously in the cortex.
Bats have to deal with multiple echo delays produced from a single call emission whenever they fly towards objects with different space depths a situation depicted in Fig. Concurrent activations in response to different echo delays were hypothesized to be important for assembling complex acoustic images in E. Figure 8d exemplifies the procedure for calculating the ICA in P. Our results indicate that in the cortex of P. However, the probability of binding objects together based on the timing of neuronal responses probability as taken from ICA values varies depending on the distance between the objects that are to be bound.
In the ICA maps of all three species Fig. However, the mechanisms by which this area—and the map it contains—yields a representation of acoustic scenes during echolocation remains largely unknown. There are three main findings in the present study i the cortical target-distance maps appear differently depending on the bat species that is studied and the parameter of the delay receptive field that is used to construct these maps; ii the target-distance representation within the map is rather blurry, because the receptive field of adjacent neurons largely overlaps; and iii the bat species that possess a target-distance map also could profit from the timing of neuronal responses to build up complex acoustic images, as do bats that do not possess chronotopic maps From the three species studied here, C.
It is unclear why these three species differ in the robustness of their cortical target-distance representations. What is clear from our data is that in the hunt for cortical topographies, experimenters should try to construct maps using several receptive-field parameters, and not just one. In the dorsal auditory cortex of bats, a topographic organization of delay-tuned neurons is more apparent for tuning measures that change more abruptly along the cortical surface that is, CD and MaxD and less apparent for measures that change at slower rates that is MinD, see Fig.
Measuring multiple receptive-field parameters also could yield more accurate interpretations about the functional roles of the auditory cortex. Such distribution could be of advantage for foraging in background cluttered environments 7. However, the latter does not imply that delay-tuned neurons of P. Overall, the results from mapping multiple DRF metrics in the dorsal auditory cortex of bats confirm the thesis that the multiparametric nature of receptive fields obscures the appearance of cortical computational maps.
The same has been shown for structural maps that is, tonotopic maps that simply reproduce the peripheral representation of sensory information.
The multiparametric nature of receptive fields is in the very essence of cortical function, although it might hamper our ability to measure maps. In bats, the multiparametric nature of receptive fields not only obscures the appearance of cortical target-distance maps but also adds a certain degree of blurriness to the map. The few neurons that respond to long delays will be active when a distant object is detected, and this activation will be localized towards the caudal portion of the map see Fig.
However, if the object is located in the immediate vicinity of the bat, then neurons throughout the map will respond and, therefore, activation within the map will not be precisely and unequivocally localized. However, the activation pattern observed in the target-distance map suggests that when flying close to an object, there will be a low grain resolution that could lead into a decreased discrimination capability based on the topology of cortical activation but also into a categorical detection of short echo delays. The activation pattern of the cortical map cannot explain fine short-distance discriminations and, therefore, precise and unequivocally localized cortical activation might not be mandatory for a precise performance.
Our data also show that bats that possess chronotopic maps also could profit from the timing of neuronal responses for the analysis of complex scenes see Fig. Assembling acoustic images by binding cortical responses to different echo delays could work properly when echolocation calls are emitted at low repetition rates that is, during the search phase of echolocation.
Even in high duty cycle echolocators such as P. Avoiding overlaps between the streams of echoes generated from successive emissions seems to be important for bats, as they shift the frequency content of their calls if echoes from the first emission are still arriving at the time when a second call is produced The experiments were conducted on the left auditory cortex of 12 adult P.
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It was impossible to determine the exact age of the bats, but all of the studied animals were capable of sustained flight and echolocated actively. These two features have been observed only in adult bats or subadults when they reach the last developmental states Experiments on P.
Individuals of C. All experiments comply with individual institutional guidelines and the Principles of Animal Care, Publication No. All experiments were conducted inside a sound-proof chamber. Bats were kept anaesthetized during the experiments. Different mixtures of anaesthetics were used in different species. A carbon microelectrode Carbostar-1, Kation Scientific, 0. The level of the presented stimuli was corrected online according to the calibration frequency response curve of the speaker.
For the construction of DRFs, the temporal position and level of one of the artificial FM sweeps defined as pulse was held constant, whereas the temporal position and level of a second sweep defined as echo were randomly changed. The frequency structure of pulse—echo pairs was adjusted so that it elicited the largest response of the delay-tuned neurons of each species. For example, P. Responses were analysed offline using custom-made Matlab scripts. Recorded spikes were discriminated using a spike-sorting procedure based on the three principal components of the spike waveforms and the posterior use of a software for unsupervised classification of multidimensional data that is, KlustaKwik 34 , Only the largest cluster of waveforms was selected for subsequent analysis.
In spite of the efforts made to isolate responses from single units, contributions of more than one unit to the studied response cannot be ruled out. DRFs were visualized as filled contour plots contourf function, Matlab. In all three species, the rostrocaudal position of neurons was determined relative to a large branch of the median cerebral artery that overlaid the Sylvian sulcus. Cortices from different animals were aligned together for the construction of composite maps. The Sylvian sulcus and median cerebral artery were used as references to determine the orientation of the ordinate axis in the bidimensional Cartesian space of analysis.
A gradient analysis was conducted to determine the spatial orientation of composite maps. The gradient of a function of two variables that is, F x, y , where F is the response property of interest that is, the CD and x and y indicate coordinates of each recording site is expressed as a collection of vectors pointing in the direction of increasing values of F. Gradient vectors were calculated in each individual animal and their angular orientation was accumulated and plotted in the form of circular scatter plots.
All circular statistics were computed using the CircStat toolbox designed for Matlab Activation maps were calculated for each animal. These maps do not depict the distribution of DRF parameters along the cortical surface but rather provide a visual representation of the neurons that are activated by a given echo delay—echo level combination. In the activation maps, the latency of responses was measured and colour coded for visual representation. Blurry topography for precise target-distance computations in the auditory cortex of echolocating bats.
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