Quanta Magazine (December 21, 2023): 2023’s Biggest Breakthroughs in Biology and Neuroscience.
Video timeline: 00:05 The Investigation of Consciousness – Our minds are constantly taking in new external information while also creating their own internal imagery and narratives. How do we distinguish reality from fantasy? This year, researchers discovered that the brain has a “reality threshold” against which it constantly evaluates processed signals. Original paper: “Subjective signal strength distinguishes reality from imagination”
04:30 Microbiomes Evolve With Us – This year, scientists provided clear evidence that the organisms in our microbiome —the collection of bacteria and other cells that live in our guts and elsewhere on our body — spread between people, especially those with whom we spend the most time. This raises the intriguing possibility that some illnesses that aren’t usually considered communicable might be.
08:43 How Life Keeps Time – The rate at which an embryo develops and the timing of when its tissues mature vary dramatically between species. What controls the ticking of this developmental clock that determines an animal’s final form? This year, a series of careful experiments suggest that mitochondria may very well serve dual roles as both the timekeeper and power source for complex cells.





“On a high-sugar diet, we find that the fruit flies’ dopaminergic neurons are less active, because the high sugar intake decreases the intensity of the sweetness signal that comes from the mouth,” Dus said. “Animals use this feedback from dopamine to make predictions about how rewarding or filling a food will be. In the high-sugar diet flies, this process is broken—they get less dopamine neuron activation and so end up eating more than they need, which over time makes them gain weight.”