The pupil as a measure of emotional arousal and autonomic activation

Abstract

Pupil diameter was monitored during picture viewing to assess effects of hedonic valence and emotional arousal on pupillary responses. Autonomic activity (heart rate and skin conductance) was concurrently measured to determine whether pupillary changes are mediated by parasympathetic or sympathetic activation. Following an initial light reflex, pupillary changes were larger when viewing emotionally arousing pictures, regardless of whether these were pleasant or unpleasant. Pupillary changes during picture viewing covaried with skin conductance change, supporting the interpretation that sympathetic nervous systemactivity modulates these changes in the context of affective picture viewing. Taken together, the data provide strong support for the hypothesis that the pupil's response during affective picture viewing reflects emotional arousal associated with increased sympathetic activity. DescriptorsPupil; Arousal; Emotion; Pleasure; Sympathetic; Skin conductance Hess (e.g., Hess & Polt, 1960) famously reported bi-directional effects of emotion on pupil change, reporting that the pupil constricted (shut down) when people viewed unpleasant pictures and dilated when they viewed pleasant pictures. These results proved difficult to replicate, however, and this early research suffered from numerous methodological difficulties, including the use of very few pictures (e.g., five), very small number of subjects (e.g., five), the method of assessing pupil change, and no statistical analysis. Libby, Lacey, and Lacey (1973) later conducted amore extensive investigation of pupillary changes during affective picture viewing, presenting 30 pictures to 34 participants while both pupil diameter and heart rate were measured. In their study, the pupil was photographed two times a second during a 15-s exposure for each picture. Then, "six clerks" scored the resulting 81,600 measurements on the basis of a wall chart onto which the negative was projected. The reported results were somewhat confusing: Although "attention-getting" pictures, a factor onto which emotionality loaded, was associated with greater pupil dilation, a second "pleasure" factor suggested that neutral pictures prompted larger pupil dilation than emotional pictures.

The developing cognitive substrate of sequential action control in 9- to 12-month-olds: Evidence for concurrent activation models

“…Larger dilations indicate motivational phenomena such as increased arousal (Bradley, Miccoli, Escrig & Lang, 2008;Laeng & Falkenberg, 2007), attention allocation (e.g. Hess & Polt, 1960), cognitive load (Kahneman & Beatty, 1966), and mental effort (Kahneman, 1973;Hess & Polt, Sequential action representation in infancy 15 1964).…”

“…Following the method Sequential action representation in infancy 28 used by Bradley et al (2008), pupil-diameter measurement began after the initial pupil reflex caused by the fixation stimulus. Visual inspection showed the light reflex to end around 500ms after effect presentation (see Figure 4) (see also Verschoor et al, in press).…”

Male bisexual arousal: A matter of curiosity?

“…Pupil dilation to stimuli indicates activation of the autonomic nervous system (Bradley, Miccoli, Escrig, & Lang, 2008) that is associated with many automatic processes such as perspiration, digestion, blood pressure, and heart rate (ten Donkelaar, Němcová, MALE BISEXUAL AROUSAL AND CURIOSITY 8! Lammens, Overeem, & Keyser, 2011).…”

Pleasure, Arousal, Dominance: Mehrabian and Russell revisited

“…In the last four decades, pleasure, arousal and to a lesser extent dominance have been used and are still used by numerous researchers in the field of environmental psychology (Bellizi, 1983;Bradley, 1992;Baker, 1992;Donovan, 1994;Dubé, 1995;Berleant, 1997;Floyd, 1997;Eastman, 1997;Kaplan et al, 1998;Wirtz, 2000;Mattila, 2001;Chebat, 2003;Stamps, 2003;Bigné, 2005;Laroche, 2005;Ryu, 2007;Arifin, 2007;Kuppens, 2008;van Hagen, 2009;Morisson, 2011;Hyun, 2011). Pleasure and arousal are also applied in other disciplines such as the neurological and neuropsychological sciences (Bradley, 1992;Bonnet, 1995;Costa, 2010;Walter, 2011), marketing research (Menon, 2002;Laroche, 2005;Wu, 2008;Lin,2010;Ha, 2010;Penz, 2011), computer systems (Palacios, 2011 and psychological research (Reisenzein, 1994;Bradley, 2008).…”