Whether it's the office holiday party where the boss got drunk or the time dad fell off the ladder while painting the living room ceiling, the brain pays particular attention to novel events and files them away for future reference. That's why some of our most memorable experiences are often those where an extraordinary event occurred. In a recent paper in the weekly journal Nature, UC Davis neuroscience researcher Robert Knight proposed that a region of the brain called the hippocampus may play a crucial role in detecting novelty. Knight's interest arose from his clinical observations that some of his amnesiac patients "seemed a bit 'flat' compared to others with respect to their normal arousal levels," he says. When Knight investigated the source, he found that damage in the hippocampal region resulted in a markedly reduced ability to respond to novelty. By recording the electrical patterns of different regions of the brain, Knight found a slower response in brains with damaged hippocampi to novel stimuli -- sound, touch and images -- although their brains' responses to the expected stimuli was preserved. "The results present a new perspective on how memories are acquired and stored," Knight said.