A recent study found that food insecurity affects brain development in mice. University of California Berkeley researchers mimicked the effects of food insecurity on juvenile mice and found that feeding history affected synapses on dopamine neurons and dopamine release. The study has implications for humans since irregular access to healthy food impacts learning and decision making later in life. The findings were published in Current Biology.
The researchers placed the mice on an irregular food schedule right before puberty onset (equivalent to late childhood in humans) and continued this schedule for 20 days through what would be the equivalent of a teen-age period in mice. A second group of well-fed mice had free access to food.
The researchers then tested cognition in adulthood by using foraging tasks in both certain and uncertain settings. Testing the well-fed and food-insecure mice as adults in both certain and uncertain settings revealed noticeable differences in cognitive flexibility. Food-insecure mice demonstrated more cognitive flexibility in uncertain situations than the well-fed mice, while well-fed mice were more flexible in more stable situations.
The researchers also noted some sex differences. In females, developmental feeding history affects adult weight. Female mice who were food insecure when growing up tended to become overweight when given unrestricted food in adulthood, and this association has also been observed in humans who have grown up with food insecurity. Male mice showed no such effect.
The researchers observed changes in the synapses of dopamine neurons and dopamine release in the dorsal striatum. Dopamine neurons play a role in learning and decision-making, so this study emphasizes the importance of increasing food security as a strategy to promote healthy brain development. UC Berkeley professor of psychology and member of the Helen Wills Neuroscience Institute Dr. Linda Wilbrecht explained that even transient food insecurity negatively affects the brain. She stated, “Food insecurity can have long-term impacts on how someone's brain functions. The ability to learn and make decisions is something that's developing during childhood and adolescence, and we are seeing how these critical skills are impacted by access to food.” An increasing number of American households with children are food insecure, (6.2% of households in 2021), so providing consistent access to food continues to be a critical public health issue.