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The Nature of Code: Simulating Natural Systems with Processing

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Gates explains, " This unsuspected connection suggests that these codes may be ubiquitous in nature, and could even be embedded in the essence of reality. If this is the case, we might have something in common with the Matrix science-fiction films, which depict a world where everything human being's experience is the product of a virtual-reality-generating computer network." To directly test whether olfactory inputs were required for stabilizing HD cell tuning in blind mice, we ablated olfactory sensory neurons (OSNs) and examined the effect on HD cell tuning. To ablate OSNs, we used a previously established chemical lesioning method 48 (see Methods). To ensure that this method was effective at ablating OSNs and severely impairing olfaction, we developed an olfactory place avoidance task in which a mouse was placed in a two-chamber arena, with one of the chambers housing an aversive olfactory substance (3-methyl-1-butanethiol 49) and the other chamber housing a neutral olfactory substance (distilled H 2O; Fig. 5b; see Methods). Mice with intact OSNs completely avoided the chamber containing the aversive olfactory substance (Fig. 5b, c). In contrast, following OSN ablation, mice showed no preference between the two chambers (Fig. 5b, c). Having established a method to reliably ablate olfaction, we tested the effect of olfactory ablation on HD cell tuning in blind animals. Olfactory ablation resulted in complete loss of HD cell tuning in ADn of blind mice (Fig. 5d, e; we pooled together rd1 and Gnat1/2 mut mice as OSN ablation affected both similarly (Supplementary Fig. 5c, d)). The percent of ADn cells that passed the criteria for being designated as HD cells drastically decreased for blind mice following olfactory ablation (Fig. 5e, Supplementary Fig. 5e, f). For some experiments, whiskers were intact during olfactory ablation, while in other animals, whiskers were ablated prior to olfactory ablation, but in both cases, olfactory ablation resulted in complete loss of HD cell tuning (Supplementary Fig. 5), again indicating that, at least in this experimental paradigm, the vibrissal system was not being used to tune HD cells. These results show that blind mice use olfactory cues to anchor their HD system.

The simple process of using binary codes to create things within the hardware of computers is very similar to how Creation creates our external reality or material world. The material world works very similar to a virtual reality. At its core, the material world is made of only light (energy) that flashes on and off to create energy codes. If we look at the computer from the outside, our artwork looks solid. If we take apart the outside layers of the computer and watch in slow motion how its hardware works beyond the microscopic level, we will see that it is made of vast streams of electrical currents. Electrical currents are another form of energy. Retired US Army Colonel says secret UFO projects should be made public by October 2030 - to beat America's rivals and get ahead of a 'catastrophic' leakArchaeologists unearthed a pot of copper coins in first major discovery at Mohenjo Daro in Pakistan, in 93 years Our results indicate that vision and olfaction can be used, either independently or in tandem, to stabilize HD cell tuning. Visual signals are believed to enter the HD system via inputs from the visual cortex to the post-subiculum and retrosplenial cortex 12. With respect to olfactory inputs, the pathway into the HD system remains unclear, though direct projections from the olfactory bulb and piriform cortex to the entorhinal cortex 54, 55 could, in turn, reach ADn via post-subiculum, which is reciprocally connected to the entorhinal cortex and ADn 56. Alternatively, olfactory signals could reach the HD system indirectly via the projection of the post-subiculum to the lateral mammillary bodies, which constitute the main subcortical input to the ADn 12. Future studies examining these pathways in more detail in both sighted and blind mice will be required to develop a better understanding of the circuitry involved.

The brain has dedicated systems for generating spatial awareness and guiding spatial navigation. In rodents, some of the most studied components of the brain’s spatial awareness system include place cells 2, grid cells 8, and head direction cells 9—although other complementary spatially-tuned cells also exist 7. To examine the effect of vision loss on part of the brain’s spatial navigation system, we decided to focus on head direction (HD) cells in the anterior dorsal nucleus (ADn) of the thalamus, where the spike rate of a majority of neurons is modulated by head direction 10, 11, but the stability of the system following vision loss has not been explored. We next examined the effect that olfactory ablation had on HD cells in blind animals. To test this, used an alternative method to reliably identify HD cells in ADn regardless of whether or not they exhibited strong tuning preferences for head direction. Previous work 50 noted that HD cells in ADn exhibit highly distinctive autocorrelograms. Similarly, we found that HD cells in ADn maintain their distinctive autocorrelograms in blind animals and following OSN ablation (Fig. 5f, Supplementary Fig. 5). Following Veijo and Peyrache 50, we implemented a machine learning approach, using Extreme Gradient Boosting 51 (XGB) to classify neurons as either HD or non-HD cells based on the shape of their autocorrelogram. First, we used our standard method to define cells as either HD cells (which rely on cells having highly selective preferred firing directions for a given head direction; see Methods) or non-HD cells, and trained the classifier using an equal number of HD and non-HD cells from WT L mice. To assess model generalizability, here, the classifier was validated on data from blind controls (pooled rd1 and Gnat1/2 mut mice; Fig. 5g). Furthermore, the classifier characterized a similar percentage of cells in ADn in blind animals with intact OSNs and following OSN ablation (Fig. 5h; see Methods). We, therefore, used the classifier to define HD cells in ADn of blind mice following OSN ablation, allowing us to compare their response properties with HD cells in blind animals with intact OSNs. By using the same model to identify HD cells in blind controls and OSN ablated animals, we found that OSN ablation led to a significant decrease in vector length (Fig. 5i). These results indicate that removing olfaction from blind animals results in untuned HD cells in ADn. Olfaction can modulate HD cell tuning in sighted animals

Daniel Shiffman

where I refers to the information content in bits/spike , P j is the probability of occupying bin j, λ j is the mean firing rate in bin j, and λ is the in-session mean firing rate of the cell. Preferred firing direction (PFD): Similar to Lozano et al. 97, PFD was defined as the angular bin with the highest normalized spike counts, whereas the mean PFD refers to the circular mean of angles. In Fig. 1e, stability was assessed based on the circular correlations of mean PFDs of exposure 1 and 2 across all recorded animals. Circular statistics were computed using the astropy module (v5.1) in Python. Intraclass correlation (ICC)

where, \(\triangle\)PFD is defined as the change in the preferred firing direction (in degrees) for each HD cell following reintroduction into the arena, and \(\triangle {{{{{{\mathrm{cue}}}}}}\; {{{{{\mathrm{is}}}}}}}\) defined as the extent (either 90° or 180°) that the visual cue was rotated. Floor rotation To eliminate (or at least greatly reduce) the sense of smell, OSNs were chemically ablated based on established methods 48, 92. In brief, mice were anesthetized with isoflurane after which a blunted 33-gauge needle was used to administer 20 μl of ZnSO4 (10 % in sterile H 2O) in both nostrils. Previous work has shown that this leads to the rapid death of OSNs 48, 92. After intranasally administering the chemical, mice were inverted to drain the excess fluid from the nasal cavity. Behavioral and electrophysiological recordings were carried out at least 24 h following OSN ablation. 2-Chamber olfactory test Outside the HD cell system, a recent study has shown that spatial maps can be found in the piriform cortex during a spatial-olfactory learning task, with spatially encoding piriform cortex cells being linked to hippocampal theta 37. Another recent study found that olfactory cues can modulate place cell responses in the hippocampus and aid in path integration 36. Consistent with these findings, earlier studies in rats found intact place cells in blind animals 59, as well as a contribution of olfactory inputs to place cell stability 60. Therefore, seeing as olfactory inputs can enable robust and stable place cell and HD cell coding in the brain, olfaction needs to be considered an important sensory system for the generation of cognitive maps. Goddess particle': Earth slammed by ultra-powerful cosmic ray, and we have no idea where it came fromFull size image The olfactory system is required for stabilizing head direction cell tuning in blind animals We find that—for normally sighted and blind animals—the removal of both visual and olfactory inputs causes the ‘hill of activity’ within HD attractor network to drift independently from the animal’s true head direction (i.e. the preferred direction of all simultaneously recorded cells drifts coherently). For some animals, there was a significant correlation between angular head velocity and angular drift velocity of PFDs. Furthermore, we found that in the absence of vision and olfaction, the decoded angular velocity (AHV) under-signaled the true AHV. To assess floor-controlled changes in PFDs of HD cells, a protocol similar to the visual cue rotation described above was adopted, except where the floor of the arena was rotated. For these experiments, to avoid possible interference of odor markings across different animals, a brand new floor was used for each mouse. At the same time, to give mice the opportunity to use olfactory odors on the floor, the floor of the arena was not cleaned between exposures. The extent to which floor rotations influenced the PFD of HD cells across animals was computed using Eq. ( 1). For cue/floor rotation sessions, 10,000 shuffles were generated using re-exposure sessions where animals were re-exposed to the same environment in the absence of any manipulation. To generate the gain values expected by chance, the gain was computed after randomly applying the experimental cue/floor rotation angles to the re-exposure data. Olfactory sensory neuron (OSN) ablation We next tested the stability of HD cells in blind mice and the extent to which their HD cell network was able to reliably encode head direction. First, we found that the preferred direction of HD cells remained stable over a single 10 min recording session (Fig. 1d), and across repeated exposure to the same arena (Fig. 1e), with levels of stability similar to what we found for sighted animals in the light (Supplementary Fig. 1). Next, we examined whether the HD cell network in ADn of blind mice was providing a reliable readout of the animal’s head direction by performing a decoding analysis 41, 42. We found that simultaneously recorded cells provided robust and stable decoding of HD (Fig. 1f). Therefore, in blind rd1 mice, HD cells are highly tuned and provide an accurate readout of head direction.

For example, when we paint a picture using a computer software, the core state of the colors and shapes in the picture are basically made of ones and zeros. We do not see our picture as ones and zeros, because the central processing unit (CPU) and its counterparts process the binary codes as colors and shapes. The greatest thing about binary codes is that there are no limits to their combinations. ... Here is an excerpt from my article titled How Frequency and Vibration Create Sacred Geometry and the Structures of Matter and Life that explains this process a little deeper: In my book titled Staradigm (published in 2011), I mentioned about this idea and roughly explained how it worked. It is great to finally hear that physicists of today are finding evidence that the Universe is a giant hologram. Air Force officer breaks silence on 'red, glowing UFO the size of a football field' hovering at low altitude over California space launch base where HD actual and HD iso refers to the actual and Isomap decoded HD, respectively. Next, the angular difference over time was unwrapped and smoothed with a Gaussian kernel (s.d. = 2), from which drift was computed as the absolute average rate of change (Fig. 7e). The shuffles shown in Fig. 7j were computed by correlating the AHV of each animal to the ADV of all other animals to generate a null distribution of AHV vs ADV correlations. Quantification of ADn unitsWorking on a branch of physics called supersymmetry, Dr. James Gates Jr., discovered what he describes as the presence of what appear to resemble a form of computer code, called error correcting codes, embedded within, or resulting from, the equations of supersymmetry that describe fundamental particles.

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