Basis For Information Transfer Research Articles

Dynamics of coupled mode solitons in bursting neural networks.

Using an electrically coupled chain of Hindmarsh-Rose neural models, we analytically derived the nonlinearly coupled complex Ginzburg-Landau equations. This is realized by superimposing the lower and upper cutoff modes of wave propagation and by employing the multiple scale expansions in the semidiscrete approximation. We explore the modified Hirota method to analytically obtain the bright-bright pulse soliton solutions of our nonlinearly coupled equations. With these bright solitons as initial conditions of our numerical scheme, and knowing that electrical signals are the basis of information transfer in the nervous system, it is found that prior to collisions at the boundaries of the network, neural information is purely conveyed by bisolitons at lower cutoff mode. After collision, the bisolitons are completely annihilated and neural information is now relayed by the upper cutoff mode via the propagation of plane waves. It is also shown that the linear gain of the system is inextricably linked to the complex physiological mechanisms of ion mobility, since the speeds and spatial profiles of the coupled nerve impulses vary with the gain. A linear stability analysis performed on the coupled system mainly confirms the instability of plane waves in the neural network, with a glaring example of the transition of weak plane waves into a dark soliton and then static kinks. Numerical simulations have confirmed the annihilation phenomenon subsequent to collision in neural systems. They equally showed that the symmetry breaking of the pulse solution of the system leaves in the network static internal modes, sometime referred to as Goldstone modes.

The Extended Brain: Cyclic Information Flow in a Quantum Physical Realm

The present knowledge of the brain neurology, collectively, is insufficient to explain higher mental processes such as (self)-consciousness, qualia, intuition, meditative states, transpersonal experiences as well as ultra rapid brain responses and functional binding between distant parts of the brain. It is proposed that super-causal space-time configurations may function as an interface between molecular transitions and the particular higher mental functions. As super-causal principles, the iso-energetic brain model as well as various quantum brain theories, are treated. Iso-energetic states of the brain may enable protein perturbation mediated information processing within a tenth of a millisecond and make use of subjective space-time configuration created in life as an emergent modality of the neural system. In addition, elementary quantum processes are seen as essential for higher brain functions, since our central nervous system forms an integral part of a dynamic universe as a non-local information processing modality. In this respect, quantum physics also allows the build-up of an individual mental knowledge domain on the basis of self-selective imprinting of a geometric space/time dimension, as induced by wave/ particle transitions in the brain. The central hypothesis of the present paper is that a versatile and rapid responding brain function requires complementary information processing mechanisms both at the iso-energetic and quantum (macro- and micro-) levels, enabling bottom up and top down information processing. This requires a nested organization of fine-tuned neural micro-sites that enable coherence/de-coherence transitions as a basis for information transfer. For a rapid and causally effective flux of information, as well as a continuous updating of a personal information domain, a “bi-cyclic” mental workspace is conceived, housing interacting and entangled wave and protein-based perturbations that build-up and retrieve information from a universal knowledge domain.

Effects of local structure of neuronal networks on spiking activity in silico

The structure of the neuronal network, including synaptic connectivity, is the basis for information transfer in the network. Various graph-theoretic measures such as degree distribution, mean geodesic path length, clustering coefficient and motif distribution exist for analysing the structure of networks [1], and each of them captures only one perspective of the properties that are crucial regarding the activity in the network. In this work, we vary the local structure of neuronal networks and observe changes in their activity in silico, i.e. in simulations where the activity of single neurons and their interaction is modeled. The local structure is analysed through the occurrence of different motifs, i.e. different patterns of connectivity. The effect of motifs on network dynamics has been widely studied in different types of networks: from the stability point of view in networks with unspecified dynamics [2], in artificial neural networks [3], and from synchronization point of view in spiking neuronal networks [4]. Our work focuses on noise-driven neuronal networks, where the activity can be characterised by spike trains of neurons in the network, and particularly by the bursting behaviour of the network. To study the local structure of networks we consider the occurrences of three separate connectivity patterns: (1) the bidirectional edges, (2) the loops of three nodes, and (3) the feed-forward motifs of triples of nodes. Networks with one of these three local connectivity patterns promoted are generated – we abbreviate these networks (L1), (L2) and (L3). In addition, different distance-dependent networks are generated, including networks with ring topology (RT) and biologically plausible topology, obtained by the NETMORPH [5] simulator (NM). All networks except for NM have binomially distributed in-degree, as is the case with the random networks (RN) that are widely used in neuronal activity simulations. Small illustrations of these network structures are shown in Figure ​Figure1.1. Neuronal activity in these types of networks of size N=100 is simulated using the model presented in [6]. The simulations show a difference in the activity of these networks. Preliminary results indicate, that network bursts occur more frequently in distance dependent networks RT and NM, especially in RT. Accordingly, the overall spiking frequency is high in these networks, but also in L3 networks. Figure 1 Different network structures. Illustration of different networks used in the present work. The red arrows and balls represent characteristics of each network, which are the following: Bidirectional edges in L1, loops of length 3 in L2, feed-forward triples ...

Bioelectrics-new applications for pulsed power technology

Electric phenomena play an important role in biophysics. Bioelectric processes control the ion transport processes across membranes, and are the basis for information transfer along neurons. These electrical effects are generally triggered by chemical processes. However, it is also possible to control such cell functions and transport processes by applying pulsed electric fields. This area of bioengineering, bioelectrics, offers new applications for pulsed power technology. One such application is prevention of biofouling, an effect that is based on reversible electroporation of cell membranes. Pulsed electric fields of several kV/cm amplitude and submicrosecond duration have been found effective in preventing the growth of aquatic nuisance species on surfaces. Reversible electroporation is also used for medical applications, e.g. for delivery of chemotherapeutic drugs into tumor cells, for gene therapy, and for transdermal drug delivery. Higher electric fields cause irreversible membrane damage. Pulses in the microsecond range with electric field intensities in the tens of kV/cm are being used for bacterial decontamination of water and liquid food. A new type of field-cell interaction, Intracellular Electromanipulation, by means of nanosecond pulses at electric fields exceeding 50 kV/cm has been recently added to known bioelectric effects. It is based on capacitive coupling to cell substructures, has therefore the potential to affect transport processes across subcellular membranes, and may be used for gene transfer into cell nuclei. There are also indications that it triggers intracellular processes, such as programmed cell death, an effect, which can be used for cancer treatment. In order to generate the required electric fields for these processes, high voltage, high current sources are required. The pulse duration needs to be short to prevent thermal effects. Pulse power technology is the enabling technology for bioelectrics. The field of bioelectrics, therefore opens up a new research area for pulse power engineers, with fascinating applications in biology and medicine.

Structural Basis of Information Transfer and Energy Transduction in Rhodopsins

Structural Basis of Information Transfer and Energy Transduction in Rhodopsins

Avian Communal Roosting: A Test of the "Patch-Sitting" Hypothesis

Major starling roosts (2,000 to 100,000 birds) cannot be fully explained on the basis of information transfer, predation, migration, or limited habitat. Radiotelemetry has revealed that each starling returns daily to feed on its own stable diurnal activity center (DAC), but stops briefly at supplemental feeding areas (SFAs) on its way to and from distant communal roosts. We test and find supported a new hypothesis (Caccamise and Morrison 1986) that DAC-based starlings select roosts that reduce commuting costs to SFAs far from their DACs. As predicted, DAC-based adults used SFAs that were nearer their roosts than their DACs, and used more distant roosts where SFAs were more widely spaced. In starlings, major communal roosts appear to be aggregations containing large numbers of patchsitting birds roosting near especially rich sources of food.

Modular automatic test equipment for commercial airlines

THE DC‐10 era is effecting subtle changes in the maintenance procedures. The basic objectives of maintaining safe equipment at a reasonable cost have not changed. The means of achieving the objectives are changing. Digital equipment, which has so much to offer in terms of reliability, capability, and cost, will require a new degree of sophistication on the part of maintenance people and equipment. Digital circuits operate on the basis of information transfer at a high cyclic rate. The control of this data transfer is the function of special purpose digital computers. Although the computer has cither serial or parallel arithmetic organisation, the output information is in a serial digital format at a reasonably high output rate. These system characteristics have resulted in maintenance people requiring a new type of electronics knowledge — the ability to work with digital logic diagrams, computer organisation and computer programs. The performance data cannot be readily evaluated by voltage measurements or analog traces on an XY recorder as has been accomplished in the past. At the same time that the equipment is becoming more difficult to understand and test, manual testing is becoming more lengthy and, in some respects, tedious because of the digital mechanisation of the functions. Airlines will not be able to afford to use their skilled maintenance technicians for routine tasks. They will be better utilised for troubleshooting problems. As a result, the relatively unsophisticated test benches of the past are becoming obsolete and are being replaced by either sophisticated manual test equipment or sophisticated automatic test equipment.