Lifeboat Foundation

Unlike computers, cells in the brain use digital and analog signals at the same time to communicate with each other, researchers have found.

The finding contradicts the belief that nerve cells in the brain communicate with each other using digital code only.

In an analog system, signals can vary continuously, while digital systems represent signals by a series of pulses. The brain uses a mixture of the two to transmit signals among cells, researchers say.

At the end of the 20th century, analog systems in computer science have been widely replaced by digital systems due to their higher computing power. Nevertheless, the question keeps being intriguing until now: is the brain analog or digital? Initially, the latter has been favored, considering it as a Turing machine that works like a digital computer. However, more recently, digital and analog processes have been combined to implant human behavior in robots, endowing them with artificial intelligence (AI). Therefore, we think it is timely to compare mathematical models with the biology of computation in the brain. To this end, digital and analog processes clearly identified in cellular and molecular interactions in the Central Nervous System are highlighted. But above that, we try to pinpoint reasons distinguishing in silico computation from salient features of biological computation. First, genuinely analog information processing has been observed in electrical synapses and through gap junctions, the latter both in neurons and astrocytes. Apparently opposed to that, neuronal action potentials (APs) or spikes represent clearly digital events, like the yes/no or 1/0 of a Turing machine. However, spikes are rarely uniform, but can vary in amplitude and widths, which has significant, differential effects on transmitter release at the presynaptic terminal, where notwithstanding the quantal (vesicular) release itself is digital. Conversely, at the dendritic site of the postsynaptic neuron, there are numerous analog events of computation. Moreover, synaptic transmission of information is not only neuronal, but heavily influenced by astrocytes tightly ensheathing the majority of synapses in brain (tripartite synapse). At least at this point, LTP and LTD modifying synaptic plasticity and believed to induce short and long-term memory processes including consolidation (equivalent to RAM and ROM in electronic devices) have to be discussed. The present knowledge of how the brain stores and retrieves memories includes a variety of options (e.g., neuronal network oscillations, engram cells, astrocytic syncytium). Also epigenetic features play crucial roles in memory formation and its consolidation, which necessarily guides to molecular events like gene transcription and translation. In conclusion, brain computation is not only digital or analog, or a combination of both, but encompasses features in parallel, and of higher orders of complexity.

Keywords: analog-digital computation; artificial and biological intelligence; bifurcations; cellular computation; engrams; learning and memory; molecular computation; network oscillations.

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Catalysts unlock pathways for chemical reactions to unfold at faster and more efficient rates, and the development of new catalytic technologies is a critical part of the green energy transition.

The Rice University lab of nanotechnology pioneer Naomi Halas has uncovered a transformative approach to harnessing the catalytic power of aluminum nanoparticles by annealing them in various gas atmospheres at high temperatures.

According to a study published in the Proceedings of the National Academy of Sciences, Rice researchers and collaborators showed that changing the structure of the oxide layer that coats the particles modifies their catalytic properties, making them a versatile tool that can be tailored to suit the needs of different contexts of use from the production of sustainable fuels to water-based reactions.

A research team at KAIST has developed the world’s first AI semiconductor capable of processing a large language model (LLM) with ultra-low power consumption using neuromorphic computing technology.

The technology aims to develop integrated circuits mimicking the human nervous system so that chips could be able to perform more sophisticated tasks that require adaption and reasoning with far less energy consumption.

Scientific Reports — Complex hybrid weighted pruning method for accelerating deep convolutional neural networks. arXiv preprint arXiv:1808.06866 (2018).

RoseTTAFold extended to predict structures of proteins bound to small molecules.

Summary: A new study explores how the human brain constructs emotions, regardless of sensory input.

By analyzing brain activity in individuals with and without sensory deprivations while they experienced the film 101 Dalmatians, researchers discovered that emotions are represented in the brain through an abstract coding system that transcends sensory modalities. This system involves a distributed network, including the ventromedial prefrontal cortex, which stores abstract representations of emotions.

The findings challenge traditional views on emotion and perception, suggesting that our emotional experiences are not solely dictated by our immediate sensory input but are instead constructed by the brain in a more abstract manner.

A research team has successfully synthesized a metal nanocluster and determined its crystal structure. Their study provides experimental evidence for understanding and designing nanoclusters with specific properties at the atomic level. Metal nanoclusters have wide-ranging applications in the biomedical field.

Their work is published in the journal Polyoxometalates.

Scientists have shown interest in ligand-protected atomically precise metal nanoclusters because they have definite atomic structures and exceptional physical and chemical properties. These properties include attributes such as luminescence, chirality, electrochemistry, and catalysis.

Retrotransposons can insert new genes into a “safe harbor” in the genome, complementing CRISPR gene editing.

The recent greenlighting of a CRISPR-Cas9 treatment for sickle cell disease underscores the efficacy of gene editing technologies in deactivating genes to heal inherited illnesses. However, the capability to integrate entire genes into the human genome as replacements for faulty or harmful ones remains unachievable.

A new technique that employs a retrotransposon from birds to insert genes into the genome holds more promise for gene therapy, since it inserts genes into a “safe harbor” in the human genome where the insertion won’t disrupt essential genes or lead to cancer.