Images with Impact

Memory and attention - is it arousal or personal impact?

Images have played a major role in elucidating neuro-cognitive mechanisms underlying emotion processing. It is widely known that emotional images both attract attention and are better remembered than neutral ones. The predominant theory is that arousal plays a causal role in determining these effects.

Camilla Croucher in her PhD research at CBU supervised by Andy Calder and Philip Barnard, critically re-examined the role of arousal and conducted several experiments showing that ratings of personal impact was a better predictor than arousal of both viewing times and image recollection (over varying retention intervals from two weeks to several months).

Images with impact are those that are judged as having an immediate effect on the viewer personally without requiring a decomposition of "how they are affected" into specific dimensions such as consequentiality/importance or personal meaningfulness and we have established that ratings of impact are not correlated with these indices. We also know that, while correlated with arousal ratings, arousal ratings do not contribute to the regression equation for impact ratings. We can't show specific images here but the negative ones would make you feel "yuk".....................

Impact appears to be a dimension related to generic felt affect. The sorts of pictures that get rated as of high personal impact are just the sort of images that appear in news media - like the famous picture of a child from the Vietnam war running down a road with burning napalm on her body.

We have followed up this work over the last three years. in an extensive collaboration between all three teams in the Emotion Group at CBU. Several further studies have been conducted using the remember-know paradigm, a flanker attention task, and a viewing task in which people have to identify upside down images in a sequence of images that vary on our impact dimension. To date we have found that impact has significant effects when arousal and distinctiveness are controlled, whereas arousal has little if any effects when impact and distinctiveness are controlled. A neuro-imaging study has also been completed that shows that Amygdala activation is related to ratings of impact as well. Preliminary psychophysiological studies seem to suggest that impact determines memory in the absence of heart rate or galvanic skin response correlates.

Reports of this work include:

Croucher, C (2006). Impact and the recollection of emotional images. Unpublished PhD Thesis, The University of Cambridge.

Calder, A.J., Ewbank, M.P., Ramponi, C. & Barnard, P. J. (2007) 'Visual impact' predicts the amygdala response to emotional images, Proceedings of the 37th annual meeting of the Society for Neuroscience. (Poster)

Ewbank, M.P., Barnard, P.J., Croucher, C.J., Ramponi, C. and Calder, A.J (2009) The amygdala response to images with impact, Social, Cognitive and Affective Neuroscience, 4(2), 127-133.

Murphy, F.C., Hill, E., Ramponi, C., Calder, A.J. & Barnard, P.J. (2010) Paying attention to emotional images with impact, Emotion, 10(5), 605-614.