placebo effect

a clinically significant response to a therapeutically inert substance or nonspecific treatment (placebo), deriving from the recipient’s expectations or beliefs regarding the intervention. It is now recognized that placebo effects accompany the administration of any drug (active or inert) and contribute to the therapeutic effectiveness of a specific treatment. For example, patients given a placebo to relieve headaches may report statistically significant reductions in headaches in studies that compare them with patients who receive no treatment at all. This term is also used more generally in nonclinical studies to indicate any effect arising from participants’ expectations regarding the study.

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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.