A review of the synaptic plasticity and memory hypothesis arguing that it is insufficient to explain memory, and proposing a broader cellular processes and memory hypothesis that includes molecular and intracellular mechanisms. Longer summary

The post reviews the synaptic plasticity and memory (SPM) hypothesis, which claims that learning and memory are stored in changes to synaptic weights between neurons. Through several compelling examples, from cannibalism rituals to heart transplant stories and single-cell learning, the author argues that while the SPM hypothesis has been productive, it is incomplete and partially wrong. The post presents evidence that memory can be stored through non-synaptic mechanisms, and proposes an alternative called the cellular processes and memory (CPM) hypothesis, which suggests memory storage involves multiple molecular and intracellular processes beyond just synaptic weights. Shorter summary

Scott Alexander responds to comments and criticism on his earlier post about 'Missing Heritability', discussing issues like gene-environment interactions, sequencing technology limitations, and the use of polygenic scores across ancestry groups. Longer summary

This post compiles and responds to notable comments on Scott's earlier post about 'Missing Heritability'. The post is structured in four sections, starting with responses from experts named in the original post, particularly Sasha Gusev who critiques the treatment of gene-environment interactions and cross-population polygenic scores. The second section features detailed technical comments from knowledgeable readers about topics like genetic interactions and sequencing technology limitations. The third section addresses specific corrections to the original post, while the final section covers various other interesting comments and discussions. Throughout, Scott engages with the criticisms and new perspectives while maintaining his original position on most key points. Shorter summary

Scott Alexander responds to comments on his COVID-19 origins debate post, addressing criticisms and maintaining his support for the zoonosis theory. Longer summary

Scott Alexander provides a detailed response to comments and criticisms of his previous post on the COVID-19 origins debate. He addresses arguments against zoonosis, clarifies misunderstandings, and discusses the methodologies used by various parties in the debate. He maintains his position favoring zoonosis over lab leak, while acknowledging the complexity of the issue and the ongoing nature of the debate. Shorter summary

A diverse collection of links covering technology, science, economics, politics, and culture, including critiques of studies, interesting scientific findings, and current events. Longer summary

This post is a collection of links to various interesting articles, studies, and news items. It covers a wide range of topics including technology, science, economics, politics, and culture. Some highlights include: a list of places branding themselves as the next Silicon Valley, a study on declining fertility in dogs, critiques of bad scientific studies, an article on antidepressant tapering, data on value drift in effective altruism, and discussions on the Mueller Report's impact on media credibility. The post also includes links to various interesting facts, studies, and developments in fields such as nutrition, drug use, e-cigarettes, and urban development. Shorter summary