Similarities and differences in perceiving threat from dynamic faces and bodies. An fMRI study

Abstract

Neuroscientific research on the perception of emotional signals has mainly focused on how the brain processes threat signals from photographs of facial expressions. Much less is known about body postures or about the processing of dynamic images. We undertook a systematic comparison of the neurofunctional network dedicated to processing facial and bodily expressions. Two functional magnetic resonance imaging (fMRI) experiments investigated whether areas involved in processing social signals are activated differently by threatening signals (fear and anger) from facial or bodily expressions. The amygdala (AMG) was more active for facial than for bodily expressions. Body stimuli triggered higher activation than face stimuli in a number of areas. These were the cuneus, fusiform gyrus (FG), extrastriate body area (EBA), temporoparietal junction (TPJ), superior parietal lobule (SPL), primary somatosensory cortex (SI), as well as the thalamus. Emotion-specific effects were found in TPJ and FG for bodies and faces alike. EBA and superior temporal sulcus (STS) were more activated by threatening bodies.

Event-Related Repetitive Transcranial Magnetic Stimulation of Posterior Superior Temporal Sulcus Improves the Detection of Threatening Postural Changes in Human Bodies

“…Such an effect is probably due to the direct anatomo-functional connections between pSTS and amygdala (Amaral and Price, 1984; Morris et al, 1998; Vuilleumier et al, 2004). The role of STS in threat perception Neurons in the posterior part of the STS respond to a variety of socially relevant stimuli such as gaze and mouth movements (Puce et al, 1998), facial expressions (Haxby et al, 2000), actions (Decety and Grèzes, 1999), biological motion (Puce and Perrett, 2003), and emotional body postures and movements (de Gelder, 2006;Kret et al, 2011;Grèzes et al, 2007;Pichon et al, 2008;de Gelder and Partan, 2009). This area contains cells whose activity is reduced when presented with pairs of successive similar body postures (Perrett et al, 2009).…”

“…Among other nodes of the sensorimotor cortical network, the posterior superior temporal sulcus (pSTS) shows stronger activation for emotional and socially relevant body movement perception (Allison et al, 2000;Puce and Perrett, 2003;Grèzes et al, 2007;Pichon et al, 2008;de Gelder and Partan, 2009;Kret et al, 2011), probably due to its anatomo-functional connections with the amygdalae (Amaral and Price, 1984;Morris et al, 1998;Rotshtein et al, 2001;Sah et al, 2003). Body movements, however, are not always fully visible and are often only implied in body postures.…”

“…In particular, the right EBA is essential in discriminating morphological body details (Urgesi et al, 2004(Urgesi et al, , 2007aMoro et al, 2008), and its activity is influenced by the emotion expressed by the body (Peelen et al, 2007;Kret et al, 2011), suggesting a large-scale representation of the emotion expressed through the body.…”

Cortico-subcortical visual, somatosensory, and motor activations for perceiving dynamic whole-body emotional expressions with and without striate cortex (V1)

“…Dynamic whole-body angry expressions were contrasted against instrumental neutral actions because the former are easily recognizable emotional stimuli, signal threat unambiguously, and trigger adaptive actions in the observers (17). Moreover, the same contrast between angry and instrumental whole-body actions has already been investigated in healthy subjects and revealed activity in all areas characteristically involved in the perception of socially significant movement and emotions, thereby enabling a direct comparison with previous findings gathered in the intact brain (17,18).…”

“…This spared ability to process simple movement is probably based on the extrageniculostriate connections that motion-sensitive human middle temporal/V5 complex (hMT/V5) has with subcortical structures like the lateral geniculate nucleus (LGN) or pulvinar nucleus of the thalamus (Pulv), as shown in humans and primates (12)(13)(14). However, compared with the perception of single moving dots or simple patches, perception of biological movement in healthy observers seems to recruit more temporal areas along the ventral visual stream, like the superior temporal sulcus (STS) (15, 16) and the fusiform gyrus (FG) (17), as well as subcortical and cortical areas related to visuomotor integration and action preparation, like the superior colliculus (SC), amygdala (Amg), and somatosensory, premotor, and motor areas (17,18). Nevertheless, it is not yet known whether patients with cortical blindness may also process complex biological movement with social and emotional relevance and which of the various extrageniculostriate pathways underlie this residual function.…”