---
title: "Functional Brain References – Brede, Hagmann, Raichle, & Snyder"
description: "## Brede Database \"Brede Database is a neuroinformatics database. It contains taxonomies of brain functions and brain regions as well as results from neuroimaging exeriments. Results from meta-analysis of the data are presented, and search engines can, e.g., retrieve nearby…"
url: "https://brainmaster.com/kb-entry/id420/"
updated: "2025-11-07"
category: Research
---

# Functional Brain References – Brede, Hagmann, Raichle, & Snyder

## Brede Database

"Brede Database is a neuroinformatics database. It contains taxonomies of brain functions and brain regions as well as results from neuroimaging exeriments.

Results from meta-analysis of the data are presented, and search engines can, e.g., retrieve nearby brain coordinates based on a give Talairach coordinate."

Since the original posting of this knowledge base article, the brede wiki has emerged to provide easier access to entered information:

Visit the Brede Wiki: [https://www.nitrc.org/projects/bredewiki/](https://www.nitrc.org/projects/bredewiki/)

[*The Brede Wiki: A social neuroinformatics web-service with structured information from neuroscience*](https://www.sciencedirect.com/science/article/abs/pii/S105381190971701X)

## The attached files below include the Hagmann article on brain hubs, and the Raichle Snyder article on the default brain.

**[Hagmann: Mapping the Structural Core of Human Cerebral Cortex](http://Mapping the Structural Core of Human Cerebral Cortex)**

**[Raichle Snyder: A default mode of brain function: A brief history of an evolving idea](https://www.sciencedirect.com/science/article/abs/pii/S1053811907001309)**

*Disclaimer: This content was generated with the assistance of AI and then reviewed and edited by BrainMaster Technologies, Inc. It is provided for educational and informational purposes only and does not constitute medical advice.*

## Mapping the Brain’s Structural and Functional Core

### Overview

This neuroimaging research reveals a tightly linked relationship between the **structural connectome** of the human brain and its **intrinsic functional networks**. Together, the works of **Hagmann et al. (2008)** and **Raichle & Snyder (2007)** define how the brain’s structural architecture supports its default functional activity.

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## Structural Core of the Human Cortex (Hagmann et al., 2008)

### Study Summary

Using **diffusion spectrum imaging (DSI)** and network analysis, Hagmann and colleagues identified a **structural core** in the **posterior medial and parietal cortices**, including regions such as the **precuneus, posterior cingulate cortex, and cuneus**. These regions exhibit:

- High **degree**, **strength**, and **betweenness centrality**
- Dense **intra- and interhemispheric connectivity**
- Strong correspondence with **resting-state functional networks**

### Key Findings

- The **posterior cingulate and precuneus** act as **connector hubs**, integrating information across frontal, temporal, and parietal modules.
- The **structural core** overlaps substantially with the **posterior components of the default mode network (DMN)**.
- There is a strong quantitative correlation (r² ≈ 0.6) between **structural and functional connectivity** within these core regions.
- The topology suggests a role in **global information integration** and **functional coherence** across the cortex.

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## The Default Mode of Brain Function (Raichle & Snyder, 2007)

### Concept and Origins

Raichle and Snyder’s work traced the discovery of the **default mode network (DMN)**—a set of brain regions that remain **metabolically active during rest** and **deactivate during goal-directed tasks**. Using **PET** and **fMRI**, they demonstrated that:

- The brain maintains **high intrinsic activity** even in the absence of tasks.
- This activity consumes the **majority of the brain’s energy budget** (60–80%).
- The DMN includes the **posterior cingulate cortex, precuneus, medial prefrontal cortex, and inferior parietal lobule**.

### Functional Significance

The DMN reflects the brain’s **intrinsic mode of operation**, supporting:

- **Self-referential processing**, **memory consolidation**, and **future planning**
- **Balance of excitation and inhibition** across large-scale neural systems
- Theoretical models of **Bayesian inference**, where the brain continuously generates and updates predictions about the environment

### Integrative Insights

The **structural hubs** identified by Hagmann et al. correspond anatomically to the **functional DMN nodes** described by Raichle & Snyder. Together, these studies suggest that:

- **Structural connectivity** provides the scaffold for **intrinsic functional dynamics**.
- The **posterior medial cortex** is both structurally central and functionally dominant.
- These insights underpin modern interpretations of **connectivity-based neurofeedback** and **clinical network modeling**.