Neurobiology Notes

Neurobiology Notes explores advancements in neuroscience focusing on brain preservation, neuroimaging techniques, neural connectivity, and memory encoding. It discusses innovative research methods, ethical considerations in brain banking, and the genetic basis of neurological and psychiatric conditions. The blog also covers technological progress in brain mapping and preservation strategies aimed at future revival possibilities.

Brain Preservation Neuroimaging Techniques Neural Connectivity Memory Encoding Brain Banking Ethics Genetics of Neurological Conditions Technological Advances in Neuroscience Preservation Strategy and Techniques

The hottest Substack posts of Neurobiology Notes

And their main takeaways

Why wasn't preservation with the goal of potential future revival started earlier in history?

176 implied HN points • 16 Jan 24
🔬 Science Biology Technology History Neuroscience Cryonics
  1. Despite preservation with the goal of future revival not being proposed for most of human history, in 1962, Evan Cooper and Robert Ettinger independently introduced the concept of cryonics.
  2. Factors influencing the delay in proposing preservation with future revival include a need for optimism in technological progress, willingness to take risks, and advances in preservation technology.
  3. Other possible reasons for the delayed start include societal restrictions, advancements in information theory, and the idea that preservation does not need to be perfect to be pursued.

Action Potentials for December

137 implied HN points • 27 Dec 23
🔬 Science Neurobiology Psychiatry Genetics Biochemistry
  1. High-pressure freezing method allows larger biospecimens to be imaged with less milling time.
  2. New study maps neurotransmitter expression in the mouse brain, revealing diversity among neuron types.
  3. Advances in neural recording technology now allow for full cortical depth recording in the brain.

Action Potentials for November

117 implied HN points • 28 Nov 23
🔬 Science Neurobiology Research Studies Brain preservation Cryonics
  1. Study on extrasynaptic neural signaling in C. elegans challenges the idea that synapses are the sole key to brain information content.
  2. Neuropeptide signaling plays a crucial role in behaviors like aggression in mice, emphasizing its significance beyond nematodes.
  3. Mouse amygdala study highlights differences in brain cell activity during memory formation and recall, shedding light on the complex processes of memory.
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What should we be measuring in brain preservation?

137 implied HN points • 11 Aug 23
🔬 Science Neurobiology Brain preservation
  1. The goal of brain preservation is to protect and store information from a person's brain for potential future revival.
  2. Structural metrics, like intact cell membrane morphology, are crucial for evaluating brain preservation methods.
  3. Connectome traceability by contemporary electron microscopy sets a high standard for brain preservation, but intact cell morphology on light microscopy can be a reasonable proxy.

Can we freeze time?

157 implied HN points • 15 May 23
🔬 Science Neurobiology Brain preservation
  1. Brain rhythms are natural patterns of neural activity measured using EEG or other neuroimaging techniques.
  2. Preserving brain structure could potentially help recapitulate brain rhythms, but uncertainties remain about the link between structure and function.
  3. Research on cryopreserving brain cells responsible for brain rhythms is valuable, but demonstrating memory retention post-preservation requires more than just measuring electrophysiological signals.

Action Potentials for June

117 implied HN points • 27 Jun 23
🔬 Science Neurobiology Psychology AI
  1. A new strategy using SUM-PAINT for protein labeling shows promise in profiling multiple proteins at high resolution.
  2. Microscopy images alone can predict neural responses to visual stimuli in Drosophila optic pathways.
  3. Combining EM and fluorescence microscopy allows for cost-effective connectomics studies in the mouse cerebellum.

Action Potentials for July

98 implied HN points • 22 Jul 23
🔬 Science Neurobiology Cryonics Astronomy Psychiatry
  1. Analysis of the Drosophila connectome reveals insights about neurotransmitters and information flow in the fly brain.
  2. Cell type annotations in the Drosophila connectome highlight the complexity and comparisons with previous mapping efforts.
  3. Developing a computational model of the Drosophila connectome provides insights into neural activity dynamics and behavioral predictions.

Action Potentials for March

137 implied HN points • 18 Mar 23
🔬 Science Neurobiology Genetics Quantum physics Cryonics
  1. A big connectomics study of Drosophila larva was published, revealing new insights into neural connections
  2. Simulated neural networks can accurately replicate properties of connectomes in different species
  3. Research proposal aims to comprehensively measure input-output functions of all 302 neurons in C. elegans, a significant project in neuroscience

Action Potentials for August

58 implied HN points • 21 Aug 23
🔬 Science Neurobiology Psychiatry Biochemistry Genetics
  1. New microscopy method combines electron microscopy with fluorescence imaging for detailed mapping of cell types, proteins, and synaptic connections in neuroscience.
  2. Memory ensembles in the brain are formed by neurons with high excitability, helping link memories and facilitating memory recall.
  3. Memory engrams exist across multiple brain areas, and bioelectric fields may coordinate memory ensembles distributed in the brain.

Action Potentials for April

98 implied HN points • 18 Apr 23
🔬 Science Neurobiology Brain preservation AI safety
  1. New study in neurobiology identifies different types of inhibitory neurons based on connectivity data
  2. Research on the C. elegans nervous system during unique developmental stages highlights connectomic differences
  3. Study on Drosophila visual system shows synaptic partner selection influenced by cell adhesion molecule expression patterns

Action Potentials for February

78 implied HN points • 19 Feb 23
🔬 Science Neurobiology Genetics Aging Mental health Biology
  1. A study found that naturally occurring place cells do not have higher excitability than non-place cells
  2. Heterozygous states can have biological effects even in diseases traditionally thought of as 'dominant'
  3. Increasing social isolation is a public health crisis, comparable to the health impact of smoking and heavy drinking

What would it mean to decode a non-trivial memory from a map of the brain?

98 implied HN points • 10 Oct 22
  1. Decoding memories from brain structures requires understanding synaptic connectivity and other structural features.
  2. The concept of non-trivial memories is still not well-defined in neuroscience.
  3. Research on decoding memories from preserved brain tissue is complex and raises ethical concerns.

Action Potentials for November

78 implied HN points • 19 Nov 22
  1. Zebrafish study allows automated reconstructions of synaptic connections
  2. Neanderthal DNA study shows gender differences in community movements
  3. Different types of mind training are necessary for growth

Action Potentials for December

58 implied HN points • 17 Dec 22
  1. Synapse sizes between neurons tend to be correlated but can be classified into two major 'buckets' based on size
  2. Study concludes current evidence for serotonergic psychedelics for depression is low due to methodologic limitations
  3. Menopausal hormone replacement therapy increases dementia risk with a dose-dependence trend

Two paths toward improved structural preservation in brain banking

58 implied HN points • 25 Oct 22
  1. Brain banking procedures vary based on available resources and can be categorized into high-quality, resource-intensive methods or more scalable options.
  2. Brain preservation methods range from perfusion fixation in animal labs to immersion fixation with acceleration techniques, each with advantages and challenges.
  3. Improvement in brain preservation can focus on achieving the best possible quality without resource constraints or ensuring 'good enough' preservation for practical, cost-effective, and scalable brain mapping studies.

Action Potentials for January

39 implied HN points • 15 Jan 23
  1. Distant memories may involve specific neurons along with connected ones
  2. Ancient DNA comes from bone or fecal remains in sediments
  3. Chelation therapy in Parkinson's may lead to worse outcomes

More evidence that dendritic structures matter for brain preservation

39 implied HN points • 16 Nov 22
  1. Removing dendritic branches from neurons can have varying effects on information processing properties
  2. Even with the removal of a large percentage of neuron inputs, function can still be maintained
  3. Preserving dendritic structures in the brain is crucial for maintaining computation and memory

Four approaches for long-term fixation-based brain banking

39 implied HN points • 26 Oct 22
  1. Brain banking involves trade-offs between preservation quality and cost
  2. Different methods like cryopreservation and room temperature storage have their own pros and cons
  3. Neuron morphology can potentially be retained even after long-term storage in formalin at room temperature

Removing the brain from the skull in brain banking: much more than you wanted to know

19 implied HN points • 04 Nov 22
  1. Removing the brain from the skull involves cutting through the skull and dissecting tethers to extract it intact.
  2. Different methods, like the anterior-only and combined posterior-anterior approach, offer options for brain extraction.
  3. Considerations include the freshness of the brain, degree of decomposition, and technology improvements in brain banking procedures.

Action Potentials for October

19 implied HN points • 18 Oct 22
  1. Researchers transplanted intact organoids into rat brains, affecting behavior
  2. CT scans usually cause minimal lifespan loss, not a major concern
  3. Effective altruists can learn from Quakers in making societal changes

That time when a bunch of people all agreed to preserve each other's brains

1 HN point • 13 Feb 23
🔬 Science Neurobiology Cryonics Brain preservation Medical Research
  1. Mutual autopsy societies in the late 1800s preserved and studied members' brains to advance science.
  2. Brain preservation methods involved using different fixatives like alcohol and formaldehyde as the science evolved.
  3. Members of these societies faced challenges like family resistance and scandal, which offer lessons for today.

Coating the surface with carbon nanotubes to improve amperometric biosensors

19 implied HN points • 13 Jan 09
  1. Coating electrodes with carbon nanotubes improves performance of amperometric biosensors by promoting electron-transfer reactions of enzymes like NADH.
  2. Carbon nanotube-coated electrodes show increased consistency, catalytic activity, and rapid response to changes in NADH concentrations compared to unmodified electrodes.
  3. Using carbon nanotubes on electrodes can reduce overvoltage and surface fouling, making them effective for detecting important compounds like NADH.

The Dark Side Of Altruism

0 implied HN points • 16 Mar 10
  1. Altruistic acts often benefit one's own in-group more than others.
  2. The 'dark side' of altruism can be seen in extreme examples like suicide bombing.
  3. Altruism can be dangerous without considering cosmopolitanism, and preference utilitarianism may provide a more balanced perspective.

Rating Interceptions Probabilistically

0 implied HN points • 17 Mar 10
  1. It's important to consider the role of luck in sports outcomes.
  2. Using a continuous rating system can provide more detailed information than binary stats.
  3. Quantifying expected value measures can lead to more reliable player performance analysis.

Book Notes Investigative Pathways

0 implied HN points • 21 Mar 10
  1. Don't be afraid to tackle big, unsolved problems in science by doing many experiments.
  2. Surrounding oneself with individuals of exceptional ability can help maintain a high standard of research.
  3. Maintaining a disciplined schedule, staying curious, and managing multiple projects can lead to scientific success.

Save The Social Animals

0 implied HN points • 29 Mar 10
  1. Save social animals to reduce their suffering.
  2. Consider policy implications to prioritize saving social animals over others.
  3. Focus on curbing suffering of animals in nature based on utilitarian perspectives.

Spending our time in worlds that don't exist

0 implied HN points • 25 Oct 08
  1. We spend a lot of time engaging with fictional worlds through activities like reading novels and watching movies.
  2. Modern society offers more opportunities to immerse ourselves in unreal worlds compared to the past.
  3. There are discussions on how society can address the trend of spending more time in fictional worlds without intruding on individual privacy.

The top 11 poems of all time

0 implied HN points • 15 Oct 08
  1. Famous poems can come from different time periods, not just modern times.
  2. The best poems are likely to be excellent, regardless of personal preferences.
  3. An economist determined the top poems by counting how often they appeared in major anthologies.

Who voted for Hitler?

0 implied HN points • 16 Oct 08
  1. Democratic voting can lead to undemocratic results, like with Hitler's party.
  2. Voter actions in Weimar elections were driven by economic self-interest.
  3. Support for racist policies can be rationalized if perceived to benefit economic interests.

Non-Great Depression parallels to the current financial crisis

0 implied HN points • 28 Oct 08
  1. The author discusses non-Great Depression parallels to the current financial crisis.
  2. Drawing too many comparisons to the Great Depression may not be wise as it is just one data point.
  3. History shows it's risky to take actions based on overinflated expectations.

Being Skeptical Of Your Skepticism

0 implied HN points • 24 Oct 10
  1. Don't discount everything an author claims just because of one mistake.
  2. We tend to categorize people as either completely truthful or totally dishonest, but reality is more complex.
  3. It's important to be aware of our own biases when judging others' claims.

Why Nature Didn't Choose Arsenic

0 implied HN points • 05 Dec 10
  1. Phosphates are preferred in biological systems due to their resistance to hydrolysis and ability to act as leaving groups for enzymatic reactions.
  2. Arsenic esters are not suitable for genetic materials because they are rapidly hydrolyzed in water, making them poor linkers for DNA and RNA bases.
  3. The possibility of a bacterium surviving without phosphates challenges concepts about the flexibility of reaction rates in physiological systems.

Would you play harder against a human than a computer?

0 implied HN points • 05 Feb 09
  1. Subjects played harder against humans than computers in a study.
  2. Brain activity differed when playing humans versus computers.
  3. The study suggests greater theory of mind use when playing against humans.