Unconscious fear influences emotional awareness of faces and voices

Abstract

Nonconscious recognition of facial expressions opens an intriguing possibility that two emotions can be present together in one brain with unconsciously and consciously perceived inputs interacting. We investigated this interaction in three experiments by using a hemianope patient with residual nonconscious vision. During simultaneous presentation of facial expressions to the intact and the blind field, we measured interactions between conscious and nonconsciously recognized images. Fear-specific congruence effects were expressed as enhanced neuronal activity in fusiform gyrus, amygdala, and pulvinar. Nonconscious facial expressions also influenced processing of consciously recognized emotional voices. Emotional congruency between visual and an auditory input enhances activity in amygdala and superior colliculus for blind, relative to intact, field presentation of faces. Our findings indicate that recognition of fear is mandatory and independent of awareness. Most importantly, unconscious fear recognition remains robust even in the light of a concurrent incongruent happy facial expression or an emotional voice of which the observer is aware.amygdala ͉ blindsight ͉ affective blindsight ͉ consciousness ͉ nonconscious processes

Posterror speeding after threat-detection failure.

“…Moreover, responses to angry conditioned faces are more resistant against extinction than happy or neutral conditioned faces (Öhman & Dimberg, 1978). (2) Stimuli such as angry faces, spiders, or aversive pictures induce behavioral effects even when subjects are unaware of them (Gelder, Morris, & Dolan, 2005;Morris, Öhman, & Dolan, 1998, 1999. (3) In visual-search tasks, the search for threatening targets requires smaller reaction times (RTs) than the search for nonthreatening targets (Öhman, Flykt, & Esteves, 2001;Flykt, 2005).…”

Faces, Bodies, Social Vision as Agent Vision, and Social Consciousness

“…A similar subcortical pathway was also envisaged in a healthy human observer when facial expressions were subliminally presented (Morris et al, 1999). Thus, attention was suddenly focused on the functional integrity of this subcortical visual pathway in patients with affective blindsight and, indeed, the activation of subcortical structures composing this pathway has been repeatedly shown in different neuroimaging studies (de Gelder & Hadjikhani, 2006;de Gelder et al, 2005;Morris et al, 2001;Pegna et al, 2005).…”

“…Other facial attributes, such as personal identity or gender, were also tested with negative results, thereby suggesting that neither movement or nonemotional facial attributes are per se the determinant of the phenomenon. More directly, in later research, affective blindsight also emerged very clearly when still images of facial expressions were used, especially if the patients were tested with indirect methodologies that typically do not require the subjects to make guesses about visual events they do not perceive consciously (Anders et al, 2004;de Gelder et al, 2005;de Gelder et al, 2001;de Gelder et al, 2002;Pegna et al, 2005). Still unanswered is the issue of whether affective blindsight is induced by nonconscious processing of overall face configuration or by individual key features in the face.…”

“…The use of brainimaging techniques, mainly fMRI, provided direct evidence regarding the functional areas and pathways sustaining affective blindsight and the neural structures involved in it (Anders et al, 2004;de Gelder & Hadjikhani, 2006;de Gelder et al, 2005;Morris, DeGelder, Weiskrantz, & Dolan, 2001;Pegna et al, 2005). With the use of electroencephalography and its temporal resolution of the order of milliseconds, one also gets a better idea of the temporal dimension (de Gelder et al, 2002;Rossion, de Gelder, Pourtois, Guerit, & Weiskrantz, 2000).…”

“…New experiments on affective blindsight investigated possible online interaction between the aware and the unaware modes of emotional processing, as well as the influence exerted by unseen emotions over ongoing recognition of other consciously perceived stimuli(de Gelder, Morris, & Dolan, 2005;de Gelder, Pourtois, van Raamsdonk, Vroomen, & Weiskrantz, 2001;de Gelder, Pourtois, & Weiskrantz, 2002;Tamietto, Weiskrantz, Geminiani, & de Gelder, 2007). This series of studies took advantage of indirect methods of testing which, as compared to direct "guessing" methods, cannot be influenced by deliberate response strategies used by the patient.…”