Lifeboat Foundation

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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Researchers at CHU Sainte-Justine and Université de Montréal have discovered a new mechanism involved in the expression of Down syndrome, one of the main causes of intellectual disability and congenital heart defects in children. The study’s findings were published today in Current Biology.

Down syndrome (SD), also called trisomy 21 syndrome, is a genetic condition that affects approximately one in every 800 children born in Canada. In these individuals, many genes are expressed abnormally at the same time, making it difficult to determine which genes contribute to which differences.

Professor Jannic Boehm’s research team focused on RCAN1, a gene that is overexpressed in the brains of fetuses with Down syndrome. The team’s work provides insights into how the gene influences the way the condition manifests itself.

Biomimetic robots, which mimic the movements and biological functions of living organisms, are a fascinating area of research that can not only lead to more efficient robots but also serve as a platform for understanding muscle biology.

Among these, biohybrid actuators, made up of soft materials and muscular cells that can replicate the forces of actual muscles, have the potential to achieve life-like movements and functions, including self-healing, high efficiency, and high power-to-weight ratio, which have been difficult for traditional bulky robots that require heavy energy sources.

One way to achieve these life-like movements is to arrange muscle cells in biohybrid actuators in an anisotropic manner. This involves aligning them in a specific pattern where they are oriented in different directions, like what is found in living organisms.

An interesting exploration of the importance of oceanic microorganisms to biogeochemical processes, how existing computational climate models do not adequately capture the complexity introduced by these microbes, and suggestions for future directions in climate modeling that better incorporate the…

Microorganisms are the engines that drive most marine processes. Ocean modelling must evolve to take their biological complexity into account.

The organic electrochemical transistor (OECT), with its organic mixed ionic–electronic conductor (OMIEC) channel, serves as an amplifying transducer of biological signals. This Review highlights OMIEC design milestones and illustrates how incorporating specific properties into OMIECs can extend OECT applications beyond biosensing.

There is no doubt that water is significant. Without it, life would never have begun, let alone continue today—not to mention its role in the environment itself, with oceans covering over 70% of Earth.

But despite its ubiquity, liquid water features some electronic intricacies that have long puzzled scientists in chemistry, physics, and technology. For example, the electron affinity, i.e., the energy stabilization undergone by a free electron when captured by water, has remained poorly characterized from an experimental point of view.

Even today’s most accurate electronic structure theory has been unable to clarify the picture, which means that important physical quantities like the energy at which electrons from external sources can be injected in liquid water remain elusive. These properties are crucial for understanding the behavior of electrons in water and could play a role in biological systems, environmental cycles, and technological applications like solar energy conversion.

Alex Rosenberg is professor of Philosophy at Duke University and has made several important contributions to the philosophy of science, biology, and social science.

0:00 intro.
2:53 scientism.
5:09 naturalism and the manifest image.
7:25 pragmatism.
10:40 intentionality.
12:38 objections to eliminativism and truth.
14:35 consciousness.
16:50 biological functions, purposes, and the selected effects theory.
22:28 reductionism.
28:05 causality.
31:02 multiple realizability.
35:13 math.
39:45 morality.
44:51 humanism, art, and history.

Continue reading “Thing in itself” »

Alex Rosenberg is the R. Taylor Cole Professor of Philosophy at Duke University. His research focuses on the philosophy of biology and science more generally, mind, and economics.

/ friction.
/ discord.
/ frictionphilo.

Continue reading “Alex Rosenberg | Intentionality, Evolution, and More” »

Eyes with lower pigment (blue or grey eyes) don’t need to absorb as much light as brown or dark eyes before this information reaches the retinal cells. This might provide light-eyed people with some resilience to SAD.

Other theories propose it happens due to an imbalance in serotonin and melatonin in the body. Serotonin makes us feel energetic, while the release of melatonin makes us feel sleepy. Since melatonin is made from serotonin, people with SAD may potentially produce too much melatonin during the winter months, leaving them feeling lethargic or down.

All these studies are inconsistent and, in some cases, contradictory. But because SAD is likely due to a combination of many biological and physiological factors working together, these different explanations for what causes SAD may well be interconnected.

Continue reading “How your eye color might increase your risk of seasonal affective disorder” »