Self-report scales are popular tools for measuring anhedonic experiences and motivational deficits, but how well do they reflect clinically significant anhedonia? Seventy-eight adults participated in face-to-face structured diagnostic interviews: 22 showed clinically significant anhedonia, and 18 met criteria for depression. Analyses of effect sizes comparing the anhedonia and depression groups to their respective controls found large effects, as expected, for measures of depressive symptoms, but surprisingly weak effect sizes (all less than =.50) for measures of general, social, or physical anhedonia, behavioral activation, and anticipatory and consummatory pleasure.
View Article and Find Full Text PDFBackground: Modulation of nicotinic acetylcholine receptors (nAChRs), specifically those containing the β2 subunit, may be effective in treating patients with major depressive disorder. Using [123I]5-I-A-85380 single photon emission computed tomography (SPECT), the authors studied the availability of β2-subunit-containing nAChRs (β2*-nAChRs) in depressed patients. To understand its molecular basis, the authors also studied β2*-nAChR binding in postmortem brain samples from depressed subjects.
View Article and Find Full Text PDFMajor depressive disorder (MDD) is a mood disorder that is not traditionally considered to affect the visual system. However, recent findings have reported decreased cortical levels of the inhibitory neurotransmitter GABA in occipital cortex. To explore possible functional consequences of MDD on visual processing, we applied a psychophysical visual motion processing task in which healthy young adults typically exhibit impaired perceptual discrimination of large high-contrast stimuli.
View Article and Find Full Text PDF