Brain News: Researchers suggest a new theory of dreams that the strangeness of our dreams help our brains better generalize our day-to-day experiences.
Dreaming has always been a mysterious area of research for Neuroscientists. Plenty of hypotheses have emerged on the brain and dreaming at night, but face several contradictions. In the past decade there has been a considerable advancement in the understanding of the biological function of sleep. Yet, no equivalent understanding of dreams has emerged.
Finally deep neural networks (DNNs) provided the novel conceptual framework helping scientists understand the evolved function of dreams. However, the common challenge with all the DNNs is overfitting as they learn, which is when performance on one dataset increases but the network’s performance fails to generalize (often measured by the divergence of performance on training versus testing datasets).
With the help of the overfitted brain hypothesis, the new study argues that human brains face the challenge of fitting too well to their daily distribution of stimuli, causing overfitting and poor generalization. It means when we repetitively perform a novel task and the condition of overfitting is triggered.
So, our brain attempts to then generalize for this task by creating dreams. This is why nightly dreams evolved to combat the brain’s overfitting during its daily learning. It helps us escape away from the statistically biased input of our daily life.
“It is the very strangeness of dreams in their divergence from waking experience that gives them their biological function,” said Erik Hoel, a research assistant professor of neuroscience at Tufts University. He further said that it is simple to turn off learning in artificial neural networks, but we can’t do that with a brain. Our brain is wired to learn new things and when life becomes boring, dreams prevent us from becoming too fitted to the model of the world. So, a dream about flying may actually help you keep your balance running.
To Know More, You May Refer To:
Hoel, E. (2021). The overfitted brain: Dreams evolved to assist generalization. Patterns, 2(5), 100244. https://doi.org/10.1016/j.patter.2021.100244