More than meets the eye: emotional stimuli enhance boundary extension effects for both depressed and never-depressed individuals

Abstract

Boundary extension is a memory phenomenon in which an individual reports seeing more of a scene than they actually did. We provide the first examination of boundary extension in individuals diagnosed with depression, hypothesising that an overemphasis on pre-existing schema may enhance boundary extension effects on emotional photographs. The relationship between boundary extension and overgeneralisation in autobiographical memory was also explored. Individuals with (n = 42) and without (n = 41) Major Depressive Disorder completed a camera paradigm task utilising positive, negative, and neutral stimuli. Across all participants, positive (d = 0.37) and negative (d = 0.66) stimuli were extended more than neutral stimuli. This effect did not differ between depressed and never-depressed participants. Across all participants, images containing objects were extended more than images containing faces. An association was also evident between extension effects in memory for perceptual space and extensions of autobiographical memory across time.