global aphasia

a severe, nonfluent form of aphasia characterized by a complete loss of or drastic reduction in both expressive language skills—one’s ability to use speech and writing to communicate—and receptive language skills—one’s ability to comprehend the speech and writing of others. Neurological lesions in global aphasia are extensive and typically involve the entire left perisylvian language zone.

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Psychology term of the day

February 16th 2025

sun compass

the use of the sun as a directional stimulus in orientation and navigation. Because the sun appears to move across the sky during the day and has different trajectories in different seasons, a sun compass must be coupled with some form of time estimation. To head south at 9 a.m., one needs to keep the sun on the left, but at 3 p.m., one needs to keep the sun on the right. Studies of several species, ranging from bees to fish and birds, have demonstrated a time-compensated sun compass. For nocturnal species, there is evidence of a star compass.