Explore all problems.

486 problems

Sidorenko’s conjecture

Do random graphs minimize the density of every fixed bipartite pattern among graphs of the same edge density?

Inverse Galois problem

Can every finite group occur as the Galois group of a finite extension of the rational numbers?

Auditory scene analysis

We can follow one voice among many. How does attention organize overlapping sounds into sources we can track?

Odor-mixture perception

A blend can smell like its ingredients or like a new odor. What determines which percept emerges?

Savings in motor adaptation

Relearning a movement adjustment can be faster than learning it first. Which memories and processes produce that advantage?

Sense of agency

We feel that our actions cause events. How do prediction and observed regularities combine to produce that feeling?

Body ownership

Vision and touch can make a rubber hand feel like your own. Which circuit processes produce this bodily attribution?

Awake hippocampal replay

While an animal pauses, its brain can rapidly replay activity associated with routes. What does that replay causally accomplish?

Compositional cognitive maps

A familiar room or obstacle can be reused in a new layout. How does the brain combine known parts into a useful map?

Event segmentation

Continuous activity feels divided into events. How do prediction and knowledge determine where one event ends and another begins?

Metacognition

Choosing an answer and judging whether it is right are different tasks. Which brain computations produce that second judgment?

Aphantasia

Some people cannot voluntarily picture a scene. Which neural differences explain lifelong absence of visual imagery?

Spontaneous thought

Thoughts arise and change direction without a new instruction. Which processes initiate and switch these self-generated episodes?