hippocampus Learning

Predictive learning induces Bayesian cognitive maps in the hippocampus

Navigation requires perception: location must be inferred from noisy and ambiguous egocentric sensory inputs, as in visual estimation of distance. However, many classical models of spatial representation implicitly assume that allocentric location is directly observable, thereby neglecting perceptual uncertainty. Here, we compare such a model with a Bayesian ideal observer that explicitly incorporates perceptual inference.

Equivalent volitional learning emerges through circuit-specific population dynamics in motor cortex and hippocampus

Learning operates across different brain circuits to associate population activity patterns with desired outcomes, and to enable volitional reactivation of those patterns to control behavior. These circuits differ profoundly in their architecture and dynamical regimes, yet which features of learning are shared across them and which arise from circuit-specific implementations remains unknown. Here, we use a brain-computer interface (BCI) to train mice to modulate the activity of selected...

Memory decline after menopause linked to loss of estrogen production in brain

A largely overlooked space between cells in women’s brains may hold the key to understanding memory loss tied to estrogen decline after menopause, reports a new preclinical Northwestern Medicine study. Nearly two-thirds of Americans with Alzheimer’s disease (AD) are women, but the reasons why women are more vulnerable are still not fully understood. Scientists have long theorized that the loss of estrogen after menopause may reduce the brain’s natural protection against memory loss and...

Sparse-to-dense coding transformation between hippocampal areas CA3 and CA1

Jeff Bezos Is Funding a Wild Hunt for the Brain’s ‘Core Algorithm’

Rob Williams knows how to pitch Jeff Bezos: You write a press release as if your product has already been built. Bezos reads it and gives a thumbs up or down. Williams went through this process a lot as an executive on Amazon’s “S-team,” in charge of software products such as Alexa, until his departure last fall.

What is a ‘normal’ memory slowdown, and when should I worry?

We’ve all been there. You walk upstairs only to find yourself wondering why you bothered. You blank on an acquaintance’s name, just as you’re introducing them.

Human-Like Neural Nets by Catapulting

Human-like Neural Nets by Catapulting Speculative proposal to create artificial neural nets with human-like performance by high-learning-rate/regularization training of overparameterized NNs to trigger catapulting/grokking. Over-parameterization as a route to true generalization would resolve many outstanding mysteries of artificial versus natural intelligence. There are many mysteries about deep learning and human intelligence, but we could describe the biggest anomaly this way: why are...

They call it 'stupid hot' for a reason: Heat muddles animal brains

They call it 'stupid hot' for a reason: Heat muddles animal brains Gaby Clark Scientific Editor Andrew Zinin Lead Editor On a blazing hot day in South Africa, female southern pied babblers can't think straight. The medium-sized black-and-white birds are trying to get at tasty mealworms behind a see-through barrier. On cooler days, the birds can quickly figure out that all they have to do is go around the small wall of plastic.

Whole-genome duplication shaped cell-type evolution in the vertebrate brain

Abstract The complex brains of vertebrates have more cell types than those of their closest relatives. Whole-genome duplications (WGDs) occurred during early vertebrate evolution1, but it is unclear whether the duplicated genes (ohnologues) facilitated cell-type evolution. Here using brain single-cell transcriptomes from five chordates—human2, mouse3, lizard4, lamprey5 and amphioxus—we report that many cell-type families with conserved core transcription factors in vertebrates do not show...

A prognostic human brain network for diffuse midline glioma

Abstract Diffuse midline gliomas (DMGs) are near-universally lethal tumours of the childhood central nervous system1,2. In animal models, DMGs form brain-wide integrated networks through neuron-to-glioma synapses3,4,5,6 and glioma-to-glioma gap junctional coupling3. This extensive connectivity robustly promotes the growth and invasion of DMG3,4,5,6,7,8,9 and other glial malignancies10,11,12 through paracrine mechanisms and direct neuron-to-glioma synapses.