Learning in multilayer neural networks (MNNs) relies on continuous updating of large matrices synaptic weights by local rules. Such locality can be exploited for massive parallelism when implementing MNNs hardware. However, these update rules require a multiply and accumulate operation each weight, which is challenging to implement compactly using CMOS. In this paper, method performing operations simultaneously (incremental outer products) memristor-based arrays proposed. The based the fact...

Although neuronal excitability is well understood and accurately modeled over timescales of up to hundreds milliseconds, it currently unclear whether extrapolating from this limited duration longer behaviorally relevant appropriate. Here we used an extracellular recording stimulation paradigm that extends the single-neuron electrophysiological experiments, exposing dynamics in individual cultured cortical neurons hitherto inaccessible. We show long-term unstable dominated by critical...

The wide range of time scales involved in neural excitability and synaptic transmission might lead to ongoing change the temporal structure responses recurring stimulus presentations on a trial-to-trial basis. This is probably most severe biophysical constraint putative time-based primitives representation neuronal networks. Here we show that spontaneously developing large-scale random networks cortical neurons vitro order which are recruited following each naturally emerging primitive...

Recent years have seen a surge in methods to track and analyze animal behavior. Nevertheless, tracking individuals closely interacting, group-living organisms remains challenge. Here, we present anTraX, an algorithm software package for high-throughput video of color-tagged insects. anTraX combines neural network classification animals with novel approach representing data as graph, enabling individual even cases where it is difficult segment from one another, or tags are obscured. The use...

Social animals display a wide range of behavioural defences against infectious diseases, some which increase social contacts with individuals (e.g. mutual grooming), while others decrease them exclusion). These often rely on the detection individuals, but this can be achieved in several ways that are difficult to differentiate. Here, we combine non-pathogenic immune challenges automated tracking colonies clonal raider ant ask whether ants detect status their partners and quantify responses...

Norrie disease (ND), an X-linked recessive disorder, is characterized by congenital blindness followed bulbar atrophy. We have examined a three-generation family in which ND part of complex syndrome with severe mental retardation, hypogonadism, growth disturbances, and increased susceptibility to infections as additional features. This apparently due interstitial deletion, evidenced the failure L1.28 DNA probe (DXS7 locus, Xp11.3) detect complementary sequences on defective X chromosome...

Responses of individual neurons to ongoing input are highly variable, reflecting complex threshold dynamics. Experimental access this dynamics is required in order fully characterize neuronal input-output relationships. The challenge practically intractable using present day experimental paradigms due the cumulative, non-linear interactions involved. Here we introduce Neuronal Response Clamp, a closed-loop technique enabling control over instantaneous response probability neuron. potential...

Significance Army ants form some of the largest insect societies on planet and famously forage in mass raids, which many thousands stream out nest search live prey. Here we show that this complex collective behavior has evolved from group raiding, is practiced by relatives army with smaller colonies. Through laboratory experiments, discovered raids follow similar organizational principles emerge when colony size artificially increased. This suggests ancient expansions size, rather than...

Oxytocin/vasopressin-related neuropeptides are highly conserved and play major roles in regulating social behavior across vertebrates. However, whether their insect orthologue, inotocin, regulates the of groups remains unknown. Here, we show that clonal raider ant Ooceraea biroi, individuals perform tasks outside nest have higher levels inotocin brains than same age remain inside nest. We also older ants, which spend more time nest, younger ants. Inotocin thus correlates with propensity to...

Neural representation is pivotal in neuroscience. Yet, the large number and variance of underlying determinants make it difficult to distinguish general physiologic constraints on representation. Here we offer a approach issue, enabling systematic well controlled experimental analysis tradeoffs, imposed by physiology neuronal populations, plausible schemes. Using <i>in vitro</i> networks rat cortical neurons as model system, compared efficacy different kinds “neural codes” represent both...

Neuronal dynamics is intrinsically unstable, producing activity fluctuations that are essentially scale-free. Here we show while these scale-free independent of temporal input statistics, they can be entrained by variation. Joint output statistics and spike train reproducibility in synaptically isolated cortical neurons were measured response to various regimes over extended time scales (many minutes). Response entrainment was found maximal when the itself possesses natural-like, statistics....

We present experimental and theoretical arguments, at the single-neuron level, suggesting that neuronal response fluctuations reflect a process positions neuron near transition point separates excitable unexcitable phases. This view is supported by dynamical properties of system as observed in experiments on isolated cultured cortical neurons, well mapping between constructs self-organized criticality membrane excitability biophysics.

The sensory response threshold is a fundamental biophysical property of biological systems that underlies many physiological and computational functions, its systematic study has played pivotal role in uncovering the principles computation. Here, we show ant colonies, which perform tasks at group level, have emergent collective thresholds. Colonies respond collectively to step changes temperature evacuate nest during severe perturbations. This characterized by group-size–dependent threshold,...

Firing rate variability at the single neuron level is characterized by long-memory processes and complex statistics over a wide range of time scales (from milliseconds up to several hours). Here, we focus on contribution non-stationary efficacy ensemble synapses-activated in response given stimulus-on variability. We present validate method tailored for controlled specific long-term activation cortical vitro via synaptic or antidromic stimulation, enabling clear separation between two...

Oguchi disease is a rare autosomal recessive form of congenital stationary night blindness. The condition associated with fundus discolouration and abnormally slow dark adaptation. Earlier studies suggested that the 48 kD protein S antigen may be involved in recovery phase light transduction. Previous cytogenetic linkage have localised gene (SAG) to chromosome 2q37.1. In present study markers which map distal 2q were typed an inbred pedigree. segregation data obtained affected subjects are...

Journal Article Heterozygous 'null allele' mutation in the human peripherin/RDS gene Get access M. Meins, Meins Search for other works by this author on: Oxford Academic PubMed Google Scholar G. Grüning, Grüning A. Blankenagel, Blankenagel 1Augenklinik der Universitat, D-69120 HeideibergGermany H. Krastel, Krastel B. Reck, Reck S. Fuchs, Fuchs E. Schwinger, Schwinger Gal * *To whom correspondence should be addressed Human Molecular Genetics, Volume 2, Issue 12, December 1993, Pages...

A family is described in which an 8 base pair deletion (nucleotides 5252-5259, codons 341-343) of the rhodopsin gene cosegregates with autosomal dominant retinitis pigmentosa (adRP). The results a shift reading frame, causing molecule extended by one residue and substantially altered at carboxyl terminus. Phenotypic expression relatively mild. In affected members, night blindness did not occur before age 16, late onset visual field loss was consistently reported. Even older individuals (59...

Five novel mutations have been identified in the gene encoding L1CAM, a neural cell adhesion protein, families with X linked hydrocephalus (XHC). Interestingly, all five are evolutionarily highly conserved Ig-like domains of protein. The two frameshift (52insC and 955delG) nonsense mutation (Trp276Ter) most probably result functional null alleles complete absence L1CAM at surface. missense (Tyr194Cys Pro240Leu) may considerably alter structure These data provide convincing evidence that XHC...

A young male with a karyotype of 46, X,+mar is described. Physical mapping the marker chromosome by using Y-specific single-copy or moderately repeated DNA sequences as molecular probes showed that, in addition to heterochromatic part Yq, considerable portion euchromatin both Yp and Yq had been lost. These findings suggest that ring Y, for generally accepted model formation implies breakages arms. The clinical features patient correlated well phenotypic changes expected from loss genetic material Y.

A 15-year-old male patient with the typical ocular symptoms of Norrie disease is described. Additionally, he presents severe mental retardation, growth disturbances, hypogonadism, and increased susceptibility to infections. This complex syndrome apparently segregating through three generations: four other relatives were blind from birth died recurrent infections between ages 15 months. The DNA sequence DXS7 locus (L1.28 probe), known be closely linked gene, was not found in patient's DNA....