ISDN2014_0313: The development of functional connectivity in the neural network supporting waking
Bibliographic record
Abstract
Adult wakefulness is sustained by the coordinated activity of interconnected neural circuitry collectively called the arousal system. One component of this system, the hypocretin/orexin (H/O) neurons of the hypothalamus, are key arousal promoters; they process information from both external and internal sources and consolidate arousal levels (Gao and Wang 2010) by directly activating Locus Coeruleus noradrenergic (LC-NA) neurons (as well as directly projecting to wide areas of the brain). Previous EEG and behavioral studies have suggested that embryos do not show waking (Mellor and Diesch 2007), but PET imaging has revealed the presence of different prenatal metabolic brain states correlated with arousal changes in chick embryos (Balaban et al., 2012). How the arousal system cell groups first become functionally connected during development and first become able to create different behavioral states is currently unknown. To better understand the development of functional connectivity between H/O and LC-NA neurons, we investigated spontaneous activity in H/O and LC-NA neurons in undisturbed chick embryos and neonatal (P1) awake chicks. Cell activity was evaluated using the expression of the immediate-early gene cFos. Relatively few H/O neurons were active on embryonic day (E) 12 (5–10%) compared with E16 (40%). The active population decreased significantly on E20 (10–30%) and in awake P1 animals showed levels similar to awake adult mammals (40%; Pompeiano et al., 2013). In contrast, activation of LC-NA neurons was very low prenatally (0% at E12, 5% at E16 and 15% at E20), also showing levels similar to awake adult mammals (40%) on P1. These different developmental activation signatures in H/O and LC-NA neurons suggest that these two systems are not functionally connected in undisturbed chick embryos until around hatching, in spite of the fact that H/O fibers and receptors are found in the LC at E12 (Cerazy et al., 2014).
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.002 | 0.003 |
| Research integrity | 0.003 | 0.003 |
| Insufficient payload (model declined to judge) | 0.064 | 0.028 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".