Lifeboat Foundation

An important aspect of human memory is our ability to conjure specific moments from the vast array of experiences that have occurred in any given setting. For example, if asked to recommend a tourist itinerary for a city you have visited many times, your brain somehow enables you to selectively recall and distinguish specific memories from your different trips to provide an answer.

Studies have shown that declarative memory—the kind of memory you can consciously recall like your home address or your mother’s name—relies on healthy medial temporal lobe structures in the brain, including the hippocampus and entorhinal cortex (EC). These regions are also important for spatial cognition, demonstrated by the Nobel-Prize-winning discovery of “place cells” and “grid cells” in these regions—neurons that activate to represent specific locations in the environment during navigation (akin to a GPS). However, it has not been clear if or how this “spatial map” in the brain relates to a person’s memory of events at those locations, and how neuronal activity in these regions enables us to target a particular memory for retrieval among related experiences.

A team led by neuroengineers at Columbia Engineering has found the first evidence that individual neurons in the human brain target specific memories during recall. They studied recordings in neurosurgical patients who had electrodes implanted in their brains and examined how the patients’ brain signals corresponded to their behavior while performing a virtual-reality (VR) object-location memory task. The researchers identified “memory-trace cells” whose activity was spatially tuned to the location where subjects remembered encountering specific objects. The study is published today in Nature Neuroscience.

Here we hypothesize that observing the visual stimuli of different categories trigger distinct brain states that can be decoded from noninvasive EEG recordings. We introduce an effective closed-loop BCI system that reconstructs the observed or imagined stimuli images from the co-occurring brain wave parameters. The reconstructed images are presented to the subject as a visual feedback. The developed system is applicable to training BCI-naïve subjects because of the user-friendly and intuitive way the visual patterns are employed to modify the brain states.

Currently, the usage of EEG-based BCIs in assistive and rehabilitation devices mostly comes down to the following scenarios:

Both humans and mice respond to fear in ways that are deeply etched in survival mechanisms that have evolved over millions of years. Feeling afraid is part of a response that helps us to survive; we learn to respond appropriately, based on our assessment of the danger we face. Importantly, part of this response involves extinguishing fear and modifying our behavior accordingly, once we have learned that a potential threat poses little or no imminent danger. The inability to adapt to fears or lay them aside is involved in disorders such as PTSD and anxiety.

The researchers from Weill Cornell demonstrated that changes in the microbiome can result in an impaired ability to extinguish fear. This was true of two groups of mice: one group had been treated with antibiotics; the other group was raised entirely free of germs. The ability of both groups of mice to extinguish fear was compared with that of control mice whose microbiome was not altered. The difference suggested that signals from the microbiome were necessary for optimal extinction of conditioned fear responses.

Neuroscientists at the Bernstein Center Freiburg (BCF) of the University of Freiburg and the KTH Royal Institute of Technology in Stockholm have decoded a significant process in the brain that in part contributes to the behavior of living beings. “One of the basic requirements for meaningful behavior is that networks in the brain produce precisely defined sequences of neuronal activity,” says Prof. Dr. Ad Aertsen of the University of Freiburg. The researchers have published the results of the cooperation with Professor Dr. Arvind Kumar of the KTH and Sebastian Spreizer, a doctoral candidate at the BCF, in the scientific journal PLoS Computational Biology.

Experiments in recent years have shown that the behavior of animals is accompanied by sequential activity of neurons in different areas of the brain. In the context of that finding, researchers world-wide have developed several models of possible mechanisms to explain how these ordered sequences come into existence. They are based primarily upon methods of supervised learning, in which the desired sequential activity is generated by means of a learning rule. Within this process, it turned out that neuronal networks can be trained to produce sequences of activity. “At the same time, we know that not every behavior is learned. Innate behavior suggests that the brain generates certain sequences without learning or training,” says Arvind Kumar, who directed the study.

Based on that, the researchers addressed the question of how an untrained brain can generate well-ordered sequences of activity. They found this requires two conditions to be met: First, a small portion of the neurons’ projected output – their connections to downstream neurons – have to prefer a specific direction. Second, neighboring neurons need to share that preferred direction. “That means that the connections of nerve cells depend on directional preferences and are spatially linked to each other. This is the key to the generation of sequential activity in neuronal networks,” explains Sebastian Spreizer. If the network is wired according to these rules, it creates a type of activity landscape similar to geographic hills and valleys. In the context of this metaphor, the sequences of neuronal activity are like the rivers in a landscape. Small changes in the spatial fabric of the nerve cells generate certain temporal and spatial sequences of neuronal activity.

A fingerprint test developed by British scientists could tell if patients are skipping medication.

Forgetting or failing to take drugs can have serious consequences, particularly for people suffering from chronic conditions or those with mental health issues.

Non-adherence to prescribed medication is a major problem for the NHS, with some studies showing only 50 per cent of people take long-term drugs as instructed, at a cost of around £300 million in wasted medicine each year.

A brain receptor believed to be linked to negative moods has been discovered in a part of the brain that contributes to pain. The paper is published in Science.

Circa 2008

A recent study demonstrates that the use of an acute, localized static magnetic field of moderate strength can result in significant reduction of swelling when applied immediately after an inflammatory injury. Magnets have been touted for their healing properties since ancient Greece. Magnetic therapy is still widely used today as an alternative method for treating a number of conditions, from arthritis to depression, but there hasn’t been scientific proof that magnets can heal.

Lack of regulation and widespread public acceptance have turned magnetic therapy into a $5 billion world market. Hopeful consumers buy bracelets, knee braces, shoe inserts, mattresses, and other products that are embedded with magnets based on anecdotal evidence, hoping for a non-invasive and drug-free cure to what ails them.

“The FDA regulates specific claims of medical efficacy, but in general static magnetic fields are viewed as safe,” notes Thomas Skalak, professor and chair of biomedical engineering at U.Va.

“What foundational values need to be in place for an ethical utilitronium shockwave?”

What foundational values need to be in place for an ethical utilitronium shockwave?
We discuss:
- (following on from a previous video) more on Nozick’s experience machines (see https://www.youtube.com/watch?v=CxBvNbuYud0).
- given that in each age there has been different conceptions of utopia, what would utopia be for a post-human superintelligence?
- classical utilitarian vs negative utilitarian approaches to the long term good of life in the universe.
- whether a perfect decision theory would be equal to negative utilitarianism.
- how much attention should we give to preferences in improving well-being beyond eliminating suffering?
- if one does believe in the objectivity of value should we be concerned about being damned in a local maximum of well-being?
- what is God’s utility function?

Continue reading “David Pearce — Foundational Values for the Future — What is God’s Utility Function?” »

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