Babies Remember Faces Despite Face Masks
Babies learn from looking at human faces, leading many parents and childhood experts to worry about possible developmental harm from widespread face-masking during the pandemic. A new study by researchers at the University of California, Davis, allays those concerns, finding that 6- to 9-month-old babies can form memories of masked faces and recognize those faces when unmasked. Michaela DeBolt, a doctoral candidate in cognitive psychology, and Lisa Oakes, a professor in the Department of Psychology and at the Center for Mind and Brain, used eye tracking to study how masks influence infants’ facial recognition. In the study, 58 babies, each seated on a parent’s lap or in a highchair, were shown pairs of masked and unmasked women’s faces on a computer screen, while cameras recorded where they looked. Because babies linger longer over unfamiliar images, the researchers could derive which faces they recognized, DeBolt said. The findings appear in a paper published in the January/February special issue of the journal Infancy, which focused on the impact of COVID-19 on infant development. The testing took place at Oakes’ Infant Cognition Lab at the Center for Mind and Brain in Davis, California, from late December 2021 to late March 2022, during a statewide mask mandate and the arrival of the coronavirus omicron variant.
Sparse, small, but diverse neural connections help make perception reliable, efficient
"How the thalamus communicates with the cortex in a fundamental feature of how the brain interprets the world," said Elly Nedivi, William R. and Linda R. Young Professor in The Picower Institute for Learning and Memory at MIT. Despite the importance of thalamic input to the cortex, neuroscientists have struggled to understand how it works so well given the relative paucity of observed connections, or "synapses," between the two regions. To help close this knowledge gap, Nedivi assembled a collaboration within and beyond MIT to apply several innovative methods. In a new study in Nature Neuroscience, the team reports that thalamic inputs into superficial layers of the cortex are not only rare, but also surprisingly weak, and quite diverse in their distribution patterns. Despite this, they are reliable and efficient representatives of information in the aggregate, and their diversity is what underlies these advantages. Essentially, by meticulously mapping every thalamic synapse on 15 neurons in layer 2/3 of the visual cortex in mice and then modeling how that input affected each neuron's processing of visual information, the team found that wide variations in the number and arrangement of thalamic synapses made them differentially sensitive to visual stimulus features. While individual neurons therefore couldn't reliably interpret all aspects of the stimulus, a small population of them could together reliably and efficiently assemble the overall picture.
Tuning into a person's individual brainwave cycle boosts learning
Scientists have shown for the first time that briefly tuning into a person's individual brainwave cycle before they perform a learning task dramatically boosts the speed at which cognitive skills improve. Calibrating rates of information delivery to match the natural tempo of our brains increases our capacity to absorb and adapt to new information, according to the team behind the study. University of Cambridge researchers say that these techniques could help us retain "neuroplasticity" much later in life and advance lifelong learning. "Our brain's plasticity is the ability to restructure and learn new things, continually building on previous patterns of neuronal interactions. By harnessing brainwave rhythms, it may be possible to enhance flexible learning across the lifespan, from infancy to older adulthood," Kourtzi said. The findings, published in the journal Cerebral Cortex, will be explored as part of the Centre for Lifelong Learning and Individualised Cognition: a research collaboration between Cambridge and Nanyang Technological University (NTU), Singapore.