NEWS BRIEFS
Anxiety cues found in the brain despite safe environment Anxiety disorders may be more than a lack of awareness of the environment or ignorance of safety, but rather that individuals cannot control their feelings and behavior. Assistant Professor of Neuroscience Benjamin SuarezJimenez, Ph.D., was first author of a study that published these findings in Communications Biology. “The patients with an anxiety disorder could rationally say, ‘I’m in a safe space,’ but we found their brain was behaving as if it was not,” said Suarez-Jimenez. Using fMRI, the researchers observed the brain activity of volunteers with general and social anxiety as they navigated a virtual reality game of picking flowers. Half of the meadow had flowers without bees, the other half had flowers with bees that would sting them – as simulated by a mild electrical stimulation to the hand.
Researchers found all study participants could distinguish between the safe and dangerous areas, however, brain scans revealed volunteers with anxiety had increased insula and dorsomedial prefrontal cortex activation – indicating their brain was associating a known safe area to danger or threat. The brain differences were the only differences seen in these patients. For example, sweat responses, a proxy for anxiety, which was also measured, failed to reveal any clear differences.
Brief period of ‘blindness’ is essential for vision
How the brain understands one voice in a noisy crowd
Researchers further cement the evidence for the important role tiny eye movements play in our ability to see letters, numbers, and objects at a distance. Researchers Michele Rucci, Ph.D., professor of Brain and Cognitive Sciences, and Janis Intoy, Ph.D., a postdoctoral research associate in Rucci’s lab, published a paper in Proceedings of the National Academy of Sciences and found that the very center of gaze undergoes drastic and rapid modulations every time we redirect our gaze, causing a brief loss of vision. During that saccades – rapid movement of the eye between fixation points – perception is suppressed and the visual system stabilizes perception. Future research will determine more about this phenomenon and how humans control eye movements to balance the saccadic suppression with the visual enhancement that follows.
New research finds a clue to how our brain is able to focus our attention on a single speaker in a crowded room with many people talking. The study, published in the Journal of Neuroscience, reveals that the brain is actually taking an extra step to understand the words coming from the speaker being listened to, and not taking that step with the other words swirling around the conversation. Using EEG brainwave recordings, the researchers had participants listen to two stories and found that the story they were instructed to pay attention to was converted into linguistic units known as phonemes – these are units of sound that can distinguish one word from another – while the other story was not. “That conversion is the first step towards understanding the attended story,” said Edmund Lalor, Ph.D., who led the study. “Sounds need to be recognized as corresponding to specific linguistic categories like phonemes and syllables, so that we can ultimately determine what words are being spoken – even if they sound different – for example, spoken by people with different accents or different voice pitches.” NEUROSCIENCE | VOL 12, 2022
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