This perspective article challenges the traditional view that categorization is a final stage of perception occurring after feature detection and memory retrieval. Instead, the authors propose that categorization is an integral computational strategy implemented throughout all stages of neural signal processing. By utilizing predictive feedback signals to organize feedforward processing, the brain creates a neural context that enables continuous grouping of objects, actions, or events into equivalence clusters.
Key points include:
- Categorization occurs from the beginning of signal processing rather than as an end stage.
- The role of predictive feedback in creating a neural context for organization.
- Evidence drawn from neuroanatomy, electrophysiology, and cognitive science.
- Implications for understanding neuropsychiatric disorders and future research directions.
Key points include:
- Categorization occurs from the beginning of signal processing rather than as an end stage.
- The role of predictive feedback in creating a neural context for organization.
- Evidence drawn from neuroanatomy, electrophysiology, and cognitive science.
- Implications for understanding neuropsychiatric disorders and future research directions.
Cognitive scientists Lisa Feldman Barrett and Earl K. Miller propose a paradigm shift in understanding brain categorization. Moving away from the traditional view that the brain compares sensory input to stored prototypes, they argue that categorization is a predictive process used to meet bodily needs through motor action plans. In this model, categories are dynamically constructed signals that shape how we perceive incoming information rather than being late-stage intellectual exercises.
Key points:
* Categorization serves as a core function for anticipating bodily needs and motor actions.
* The brain is predictive rather than reactive, preparing responses before sensory processing is complete.
* Anatomical evidence shows that feedback connections from memory to sensory regions significantly outweigh feedforward signals.
* Misalignment in these processes may contribute to conditions like depression or autism.
Key points:
* Categorization serves as a core function for anticipating bodily needs and motor actions.
* The brain is predictive rather than reactive, preparing responses before sensory processing is complete.
* Anatomical evidence shows that feedback connections from memory to sensory regions significantly outweigh feedforward signals.
* Misalignment in these processes may contribute to conditions like depression or autism.
Claude-Mem is a persistent memory compression system designed specifically for Claude Code and Gemini CLI. It automatically captures tool usage observations, generates semantic summaries via AI, and injects relevant context into future sessions to ensure continuity of knowledge across coding projects.
Key features include:
* Persistent memory that survives session restarts
* Progressive disclosure architecture for token-efficient retrieval
* Skill-based search using MCP tools (search, timeline, get_observations)
* Hybrid semantic and keyword search powered by Chroma vector database and SQLite
* Privacy controls via specific tags to exclude sensitive data
* A web viewer UI for real-time memory stream monitoring
Key features include:
* Persistent memory that survives session restarts
* Progressive disclosure architecture for token-efficient retrieval
* Skill-based search using MCP tools (search, timeline, get_observations)
* Hybrid semantic and keyword search powered by Chroma vector database and SQLite
* Privacy controls via specific tags to exclude sensitive data
* A web viewer UI for real-time memory stream monitoring
A single CLAUDE.md file to improve Claude Code behavior, derived from Andrej Karpathy's observations on LLM coding pitfalls.
Post-Mortem: Backup Failure via Filesystem Limit Exhaustion
**Incident Summary:**
A website backup process failed after a single 1.6MB GIF (a "Friends" reaction animation) was replicated 246,173 times within the storage system, inflating its size to 377GB and triggering filesystem limits.
**Root Cause:**
The issue stemmed from a security policy in the Discourse platform's "secure uploads" feature. To maintain security contexts, when a file moves between private and public scopes (e.g., PM to public post), the system generates a new copy with a randomized SHA1 hash rather than referencing the original. High community usage of a specific GIF caused massive data duplication.
**Technical Failure Chain:**
1. **Data Inflation:** Excessive duplication led to 377GB of backup bloat from a single asset.
2. **Failed Mitigation (Hardlinks):** An initial attempt to use hardlinks to group identical hashes failed because the number of duplicates exceeded the **ext4 filesystem limit of ~65,000 hardlinks per inode**. This resulted in approximately 181,000 fallback downloads, failing to resolve the bloat.
**Resolution:**
New logic was implemented for the backup process: The system attempts to create hardlinks first; if the filesystem returns an `EMLINK` error (too many hardlinks), it automatically switches to creating a local copy and designates that as the "primary" file until the limit is reached again. This ensures compatibility across all filesystems without manual configuration.
**Incident Summary:**
A website backup process failed after a single 1.6MB GIF (a "Friends" reaction animation) was replicated 246,173 times within the storage system, inflating its size to 377GB and triggering filesystem limits.
**Root Cause:**
The issue stemmed from a security policy in the Discourse platform's "secure uploads" feature. To maintain security contexts, when a file moves between private and public scopes (e.g., PM to public post), the system generates a new copy with a randomized SHA1 hash rather than referencing the original. High community usage of a specific GIF caused massive data duplication.
**Technical Failure Chain:**
1. **Data Inflation:** Excessive duplication led to 377GB of backup bloat from a single asset.
2. **Failed Mitigation (Hardlinks):** An initial attempt to use hardlinks to group identical hashes failed because the number of duplicates exceeded the **ext4 filesystem limit of ~65,000 hardlinks per inode**. This resulted in approximately 181,000 fallback downloads, failing to resolve the bloat.
**Resolution:**
New logic was implemented for the backup process: The system attempts to create hardlinks first; if the filesystem returns an `EMLINK` error (too many hardlinks), it automatically switches to creating a local copy and designates that as the "primary" file until the limit is reached again. This ensures compatibility across all filesystems without manual configuration.
Jerome Ito is opening Yutori in Palo Alto, a massive 5,000-square-foot destination designed to bring the culture of Japanese konbinis, cafes, and artisan markets to the Peninsula. The space features a serene outdoor garden with cherry blossom trees and will evolve from a daytime cafe and deli into a full-service restaurant and bar.
Key highlights include:
- A cafe serving specialty matcha, miso lattes, and pastries by chef Janet Tong.
- A konbini-inspired market offering Japanese sandos, bento boxes, sashimi, and imported goods like ceramics and knives.
- An upcoming restaurant phase featuring family-style dishes such as grilled fish, Japanese-Italian pastas, and Wagyu steak.
- An expansive outdoor patio and stone garden for community events and seasonal festivals.
Key highlights include:
- A cafe serving specialty matcha, miso lattes, and pastries by chef Janet Tong.
- A konbini-inspired market offering Japanese sandos, bento boxes, sashimi, and imported goods like ceramics and knives.
- An upcoming restaurant phase featuring family-style dishes such as grilled fish, Japanese-Italian pastas, and Wagyu steak.
- An expansive outdoor patio and stone garden for community events and seasonal festivals.
Write Pandas Like a Pro With Method Chaining Pipelines
Master method chaining, assign(), and pipe() to write cleaner, testable, production-ready Pandas code
Master method chaining, assign(), and pipe() to write cleaner, testable, production-ready Pandas code
A new study from the University of East Anglia suggests that social proximity plays a significant role in how gut bacteria are exchanged between individuals. By observing Seychelles warbler colonies on Cousin Island, researchers found that birds with close social bonds, such as breeding pairs and helpers at a nest, shared more similar anaerobic gut bacteria than those without close contact. Because these microbes cannot survive in open air, they must be transferred through direct, intimate interactions.
This research implies similar dynamics may exist among humans, where living with partners, family members, or housemates facilitates the exchange of beneficial microbes through daily physical contact and shared environments, potentially influencing household immunity and digestive health.
Key points:
* Social closeness drives anaerobic gut bacteria transmission via direct contact.
* Research conducted on Seychelles warblers provides evidence that social roles influence microbiomes.
* Anaerobic microbes require intimate interaction to spread as they cannot survive in the environment.
* Findings suggest human domestic life and social interactions may shape individual microscopic ecosystems.
This research implies similar dynamics may exist among humans, where living with partners, family members, or housemates facilitates the exchange of beneficial microbes through daily physical contact and shared environments, potentially influencing household immunity and digestive health.
Key points:
* Social closeness drives anaerobic gut bacteria transmission via direct contact.
* Research conducted on Seychelles warblers provides evidence that social roles influence microbiomes.
* Anaerobic microbes require intimate interaction to spread as they cannot survive in the environment.
* Findings suggest human domestic life and social interactions may shape individual microscopic ecosystems.
This study investigates whether the human brain has an organized baseline state of function that is suspended during goal-directed tasks. Researchers used positron-emission tomography (PET) to measure the oxygen extraction fraction (OEF)—the ratio of oxygen used by the brain to oxygen delivered by blood—in resting adults.
Key findings include:
1. Uniformity at Rest: Despite significant differences in blood flow and oxygen consumption between gray and white matter, the OEF remains remarkably uniform across the brain during a resting state (eyes closed, awake).
2. Defining Baseline: The researchers propose that this uniform OEF represents an equilibrium state of local neuronal activity, serving as a true physiological baseline.
3. Deactivation Patterns: Many brain regions, particularly in the visual system, consistently show decreases in activity (deactivations) during cognitive tasks.
4. Validation: By measuring the OEF at rest, the study confirms that these task-induced decreases are not merely artifacts of an undefined control state but represent a genuine drop from a stable baseline level of brain function.
The results suggest the existence of a default mode of brain function that is active when specific goal-directed behaviors are not being performed.
Key findings include:
1. Uniformity at Rest: Despite significant differences in blood flow and oxygen consumption between gray and white matter, the OEF remains remarkably uniform across the brain during a resting state (eyes closed, awake).
2. Defining Baseline: The researchers propose that this uniform OEF represents an equilibrium state of local neuronal activity, serving as a true physiological baseline.
3. Deactivation Patterns: Many brain regions, particularly in the visual system, consistently show decreases in activity (deactivations) during cognitive tasks.
4. Validation: By measuring the OEF at rest, the study confirms that these task-induced decreases are not merely artifacts of an undefined control state but represent a genuine drop from a stable baseline level of brain function.
The results suggest the existence of a default mode of brain function that is active when specific goal-directed behaviors are not being performed.
Researchers from the Chinese Academy of Sciences have identified a new organizational principle within the default mode network (DMN) that explains how it supports both internal thoughts and external perceptions. The study reveals that the DMN is composed of distinct subregions acting as either senders or receivers of information, allowing the brain to flexibly shift between memory-driven thought and sensory perception.
Key findings include:
* Identification of receiver-like subregions that support information integration during perception through stronger connectivity with heteromodal association networks.
* Identification of sender-like subregions that guide memory-based behavior via coupling with sensorimotor systems.
* Evidence that these subdivisions correspond to specific cognitive modes, such as face recognition versus memory-guided decisions.
Key findings include:
* Identification of receiver-like subregions that support information integration during perception through stronger connectivity with heteromodal association networks.
* Identification of sender-like subregions that guide memory-based behavior via coupling with sensorimotor systems.
* Evidence that these subdivisions correspond to specific cognitive modes, such as face recognition versus memory-guided decisions.
