High levels of stress have been shown to have negative effects on memory and cognitive function. Stress can impair the brain's ability to encode and retrieve memories, as well as hinder cognitive processes such as attention, decision-making, and problem-solving. This is due to the release of stress hormones, such as cortisol, which can interfere with the functioning of the hippocampus and prefrontal cortex, areas of the brain critical for memory and cognition. Therefore, it is true that high levels of stress can lead to poor memory and less cognitive function.