Posed facial emotional expression in brain-damaged patients

Posed emotional facial expression was examined in brain-damaged adults with right (RBD) or left (LBD) hemisphere cerebrovascular lesions and in matched normal controls (NC). Subjects were videotaped while posing eight facial expressions (positive and negative) under two elicitation conditions (verbal command and visual imitation). Expressions were rated by four na?ve judges for intensity, category accuracy, and valence accuracy. RBDs were significantly more impaired than LBDs or NCs on category and valence accuracy, while LBDs posed expressions with significantly more intensity than RBDs or NCs. These findings held for positive emotions only. The results for category accuracy replicate an earlier report (Borod et al., 1986) which utilized a different rating procedure. Finally, expressions posed to visual imitation were rated as more intense and more accurate than those posed to verbal command.     

Spontaneous facial expression of emotions in brain-damaged patients

Spontaneous facial expression of emotion was studied in two groups of right (N = 23) and left (N = 39) brain-damaged patients and in a control group of normal subjects (N = 28). To elicit emotions four short movies, constructed to produce positive, negative or neutral emotional responses, were used. The method used to assess the facial expression of emotions was the Facial Action Coding System. Brain-damaged patients showed less facial responses to emotional stimuli than normal controls, but no difference was observed between subjects with right and left-sided lesions either with global or disaggregated data analyses, inconsistent with the hypothesis of a specialization of the right hemisphere for facial emotional expressions. An unexpected difference was observed in response to the unpleasant movie. Both normal controls and left brain-damaged patients often averted their gaze from the screen when unpleasant material was displayed, whereas right brain-damaged patients rarely showed gaze aversion. This finding suggests that the degree of emotional involvement or manner of coping with stressful input may be reduced as a result of right brain damage.     

The perception of positive and negative facial expressions in unilateral brain-damaged patients: A meta-analysis

How the brain is lateralised for emotion processing remains a key question in contemporary neuropsychological research. The right hemisphere hypothesis asserts that the right hemisphere dominates emotion processing, whereas the valence hypothesis holds that positive emotion is processed in the left hemisphere and negative emotion is controlled by the right hemisphere. A meta-analysis was conducted to assess unilateral brain-damaged individuals’ performance on tasks of facial emotion perception according to valence. A systematic search of the literature identified seven articles that met the conservative selection criteria and could be included in a meta-analysis. A total of 12 meta-analyses of facial expression perception were constructed assessing identification and labelling tasks according to valence and the side of brain damage. The results demonstrated that both left and right hemisphere damage leads to impairments in emotion perception (identification and labelling) irrespective of valence. Importantly, right hemisphere damage prompted more pronounced emotion perception impairment than left hemisphere damage, across valence, suggesting right hemisphere dominance for emotion perception. Furthermore, right hemisphere damage was associated with a larger tendency for impaired perception of negative than positive emotion across identification and labelling tasks. Overall the findings support Adolphs, Jansari, and Tranel (2001) model whereby the right hemisphere preferentially processes negative facial expressions and both hemispheres process positive facial expressions.     

Atypical perception processing and facial emotion disorder in autism

Introduction

Autistic syndrome is defined by several abnormalities, mainly affecting social interaction skills. Disorders of the processes of processing facial and emotional stimuli, and particularly avoidance of gaze, have also been reported in this disorder. Some authors have suggested that these abnormalities may be explained, or at least contributed to, by the social disorder observed in this syndrome. The aim of this study was therefore to improve the understanding of the processes involved in perception AND the representation of faces expressing emotion in subjects with autism spectrum disorders (ASDs).

Methods

Eleven children with ASDs (mean developmental age 7 years 11 months) and eleven normally developing children (mean age 7 years 9 months) took part in three experiments. The first involved overall discrimination of emotions using photographs of faces expressing six basic emotions, the second required local emotional discrimination on the basis of isolated elements of the face (photographs of eyes and mouths isolated from the rest of the face), and for the third the children were asked to create faces expressing emotions by means of a jig-saw puzzle format, using photographs of isolated elements of the face (overall representation necessitating local discrimination).

Results

Our findings revealed that the normally developing children had difficulties with the process of local discrimination of emotions: their performance improved when overall perception was possible. In contrast, and astonishingly, the children with ASD were more able to discriminate isolated eyes expressing emotion than the controls, but their performance declined when overall processing was required.

Discussion

Our results suggested that the emotional disorders observed in ASDs might be explained by greater skills in the processing of local information. This might explain the inability of children with ASDs to achieve coherent perception of their social environment and might also lead to the withdrawal that is characteristic of this disorder. These results also suggest that the gaze avoidance that is characteristic of individuals with ASDs is eliminated when eyes are presented alone. This gaze avoidance therefore seems to be related to the complexity and variability of this type of stimulus and not to the social nature of the stimulus.     

Lateralization for the expression and perception of facial emotion as a function of age

In order to test the hypothesis of right hemisphere changes with age, this study examined lateralization for facial emotion in young, middle-aged, and older women (N = 90). For expression, subjects were photographed while posing positive and negative emotions. Composite photographs were created and rated for intensity. For perception, subjects were required to make intensity judgements about emotional chimeric faces. Overall, subjects demonstrated significant left-sided facial asymmetry for expression and significant left hemispace biases for perception. The findings for facial expression were not influenced by emotional valence or resting face asymmetries. There were no changes in lateralization as a function of age for either expression or perception. Taken together, these findings lend support to the notion that the right hemisphere mediates emotional processing across the adult life span.     

An analysis of categorical perception of facial emotion in schizophrenia

BACKGROUND: Emotion perception deficits have been extensively documented in schizophrenia and are associated with poor social functioning. Yet fundamental questions about the nature and scope of these impairments remain unanswered from commonly used experimental tasks. An alternative categorical perception paradigm that focuses on distinguishing boundaries between emotions was used to evaluate whether schizophrenia patients demonstrate atypical patterns of categorical perception and a negativity bias in the identification of ambiguous facial expressions. METHOD: 47 schizophrenia outpatients and 31 nonpsychiatric controls completed a forced-choice emotion identification task. Stimuli consisted of a series of digitized facial images that were morphed in 10% signal intensity increments along continua between pairs of emotions (happy-sad; fearful-happy; angry-fearful; angry-sad) and presented in a random order. For each emotion continuum, measures of the response slope and the location of the boundary shift point between emotions were calculated for each group. RESULTS: The schizophrenia group demonstrated significantly shallower response curves than controls across all emotion continua. Despite these generally less precise demarcations between emotions, patients did not significantly differ from controls in the location of the shift point between emotions on any of the continua. CONCLUSIONS: Schizophrenia patients demonstrated impaired categorical perception of facial expressions with generally less sharp categorizations of ambiguous stimuli to one emotion category or another. However, patients did not demonstrate a negativity bias in their processing of ambiguous facial expressions. The emotional continuum paradigm can help to clarify the nature and boundaries of affect perception deficits in schizophrenia.     

Effects of lesion variables and emotion type on the perception of facial emotion.

The purpose of this study was to consider the effects of valence, motoric direction (i.e., approach/withdrawal), and arousal on the perception of facial emotion in patients with unilateral cortical lesions. We also examined the influence of lesion side, site, and size on emotional perception. Subjects were 30 right-hemisphere-damaged (RHD) and 30 left-hemisphere-damaged (LHD) male patients with focal lesions restricted primarily to the frontal, temporal, or parietal lobe. Patient groups were comparable on demographic and clinical neurological variables. Subjects were tested for their ability to match photographs of four facial emotional expressions: happiness, sadness, fear, and anger. Overall, RHD patients were significantly more impaired than LHD patients in perceiving facial emotion. Lesion side, but not site, was associated with motoric direction and valence dimensions. RHD patients had specific deficits relative to LHD patients in processing negative and withdrawal emotions; there were no group differences for positive/approach emotions. Lesion size was not significantly correlated with accuracy of emotional perception.     

Asymmetry of facial expression in spontaneous emotion

The observation that emotional expressions are more intense on the left side of the face is consistent with other evidence of the importance of the right hemisphere in emotional communication. However, the question has been raised whether it is truly spontaneous emotional expressions or only posed facial displays that show a left-sided asymmetry. We surreptitiously examined facial asymmetry during spontaneous emotional expressions as subjects remembered happy or sad experiences. These were contrasted with the subjects' posed expressions of happy or sad emotions. Both of these procedures resulted in more intense expressions on the left side of the face. The left-sided advantage was stronger during the spontaneous than the posed displays, and was observed for both happy and sad emotions.     

Using FACS vs. communication scores to measure spontaneous facial expression of emotion in brain-damaged patients: a reply to Mammucari et al. (1988)

Buck and Duffy (1980) and Borod et al. (1985) found evidence of deficits in spontaneous expressiveness in right brain-damaged (RBD) patients relative to LBD patients and controls. Using FACS, Mammucari et al. (1988) failed to replicate this result and questioned our methods and findings. This paper replies (a) that Mammucari et al. (1988)'s review of our work is selective and misleading; (b) that there are aspects of their study that can account for their null results, including the insufficient sensitivity of FACS for the measurement of spontaneous expressiveness; and (c) that the results of Mammucari et al. (1988) regarding "aversive eye movements" to a negative film in LBD and control, but not RBD, patients are in fact compatible with our findings. This paper also suggests a general strategy for the objective and comprehensive analysis of spontaneous emotional expressiveness.     

Deficits in facial emotion perception in adults with recent traumatic brain injury

We examined whether facial emotion perception was compromised in adults with recent traumatic brain injury (TBI). Few studies have examined emotion perception in TBI; those that have, examined chronic patients only. Recent and chronic TBI populations differ according to degree of functional reorganization of the brain, use of compensatory strategies, and severity of cognitive impairments--any of which might differentially affect presentation of emotion perception deficits. A secondary aim of the study was to utilize the TBI population--in whom diffuse axonal injury (DAI) is a cardinal neurological feature--to examine the suggestion of Adolphs et al. [Journal of Neuroscience 20(7) (2000) 2683] that damage to white matter tracts should give rise to emotion perception deficits. METHODS: Thirty TBI participants and 30 age-matched controls were tested. A 2 x 3 mixed design was employed. The dependent variable was accuracy on neutral and emotional face perception tests. RESULTS: (1) The TBI group performed significantly less accurately than the matched controls on the facial emotion perception tasks, whereas the groups performed equivalently on a non-emotional face perception control task. (2) A sub-group of TBI participants without evidence of focal injury to areas of the brain most commonly implicated in facial emotion perception was as impaired on the emotion perception tasks as a second sub-group who had sustained focal lesions to these areas. This suggests an alternative neurological mechanism for deficits in the first sub-group, such as DAI. CONCLUSIONS: Patients with recently acquired TBI are impaired in their ability to perceive emotions in faces. DAI alone may cause facial emotion perception deficits.     

Remediation of facial emotion perception in schizophrenia: concomitant changes in visual attention

The study examined changes in visual attention in schizophrenia following training with a social-cognitive remediation package designed to improve facial emotion recognition (the Micro-Expression Training Tool; METT). Forty out-patients with schizophrenia were randomly allocated to active training (METT; n=26), or repeated exposure (RE; n=14); all completed an emotion recognition task with concurrent eye movement recording. Emotion recognition accuracy was significantly improved in the METT group, and this effect was maintained after one week. Immediately following training, the METT group directed more eye movements within feature areas of faces (i.e., eyes, nose, mouth) compared to the RE group. The number of fixations directed to feature areas of faces was positively associated with emotion recognition accuracy prior to training. After one week, the differences between METT and RE groups in viewing feature areas of faces were reduced to trends. However, within group analyses of the METT group revealed significantly increased number of fixations to, and dwell time within, feature areas following training which were maintained after one week. These results provide the first evidence that improvements in emotion recognition following METT training are associated with changes in visual attention to the feature areas of emotional faces. These findings support the contribution of visual attention abnormalities to emotion recognition impairment in schizophrenia, and suggest that one mechanism for improving emotion recognition involves re-directing visual attention to relevant features of emotional faces.     

Sex differences in asymmetry in the facial expression of emotion

Two measures of facial asymmetry (preferred eye winking and eyebrow raising facility) were taken for 255 subjects. As predicted, males displayed significantly greater left-side facial asymmetry than did females, although the sex differences were not great. The findings lend support to prior research suggesting hemispheric asymmetry in the control of emotional expression.     

Understanding facial emotion perception in Parkinson's disease: the role of configural processing

Parkinson's disease (PD) has been frequently associated with facial emotion recognition impairments, which could adversely affect the social functioning of those patients. Facial emotion recognition requires processing of the spatial relations between facial features, known as the facial configuration. Few studies, however, have investigated this ability in people with PD. We hypothesized that facial emotion recognition impairments in patients with PD could be accounted for by a deficit in configural processing. To assess this hypothesis, three tasks were proposed to 10 patients with PD and 10 healthy controls (HC): (i) a facial emotion recognition task with upright faces, (ii) a similar task with upside-down faces, to explore the face inversion effect, and (iii) a configural task to assess participants’ abilities to detect configural modifications made on a horizontal or vertical axis. The results showed that when compared with the HC group, the PD group had impaired facial emotion recognition, in particular for faces expressing anger and fear, and exhibited reduced face inversion effect for these emotions. More importantly, the PD group's performance on the configural task to detect vertical modifications was lower than the HC group's. Taken together, these results suggest the presence of a configural processing alteration in patients with PD, especially for vertical, second-order information. Furthermore, configural performance was positively correlated with emotion recognition for anger, disgust, and fear, suggesting that facial emotion recognition could be related, at least partially, to configural processing.     

The effect of left and right poses on the expression of facial emotion

Research, using composite facial photographs has demonstrated that left-left composites are more emotionally expressive than are right-right composites. The present study investigated whether hemifacial asymmetries in expression are apparent in photographs, that feature one side of the face more than the other. Photographs were taken of the models who turned their heads: (a) 15 degrees to the left, (b) 15 degrees to the right or (c) faced directly towards the camera. It was predicted that left hemiface and midline photographs would be judged as more emotionally expressive than right hemiface photographs, where the left hemiface is less prominent. Three hundred and eighty-four participants viewed photographs of the three posing conditions, and rated each photograph along an emotional expressivity scale. Midline and left hemiface portraits were rated as more emotionally expressive than were right hemiface portraits. To investigate whether this effect was caused by observer's aesthetic/perceptual biases, mirror-reversed versions of the three posing conditions were included. Left hemiface and midline portraits were rated as more emotionally expressive, irrespective of whether they were mirror-reversed. It was concluded that head turns of just 15 degrees can bring about significant changes in the perceived emotionality. The relevance of these findings to painted portraits, which feature the left hemiface more than the right, is discussed.     

Neurobiology of emotion perception I: The neural basis of normal emotion perception.

There is at present limited understanding of the neurobiological basis of the different processes underlying emotion perception. We have aimed to identify potential neural correlates of three processes suggested by appraisalist theories as important for emotion perception: 1) the identification of the emotional significance of a stimulus; 2) the production of an affective state in response to 1; and 3) the regulation of the affective state. In a critical review, we have examined findings from recent animal, human lesion, and functional neuroimaging studies. Findings from these studies indicate that these processes may be dependent upon the functioning of two neural systems: a ventral system, including the amygdala, insula, ventral striatum, and ventral regions of the anterior cingulate gyrus and prefrontal cortex, predominantly important for processes 1 and 2 and automatic regulation of emotional responses; and a dorsal system, including the hippocampus and dorsal regions of anterior cingulate gyrus and prefrontal cortex, predominantly important for process 3. We suggest that the extent to which a stimulus is identified as emotive and is associated with the production of an affective state may be dependent upon levels of activity within these two neural systems.     

Effect of levodopa on healthy volunteers' facial emotion perception: an FMRI study

OBJECTIVE: A link between the brain dopaminergic (DA) system and emotional processing seems to be supported by the DA nature of neural systems surrounding emotional recognition, the occurrence of emotional deficits in medical disorders involving a DA dysfunction, and the effect of DA agonists or antagonists on emotional processing. The authors tested the influence of levodopa administration on emotional processing in a functional MRI (fMRI) study of 10 elderly volunteers. METHODS: A placebo-controlled, cross-over experimental design was used. Subjects received either levodopa (100 mg) or placebo in 2 fMRI sessions. Performance was evaluated with a passive facial emotion perception test. RESULTS: During the placebo situation, the region-of-interest (ROI) analysis showed that emotional processing activated the bilateral amygdala. In levodopa volunteers, this activation was missing. The statistical comparison between the 2 situations (emotional vs control condition) revealed a highly significant reduction in activation of the bilateral amygdala for the levodopa fMRI session (P corrected <0.0001 in the left and P = 0.002 in the right amygdala). CONCLUSION: These results suggest that administration of levodopa to healthy volunteers directly or indirectly impairs the amygdalar activation during the emotional perception task. The authors hypothesized that amygdala activation may conform to an inverted U-shaped function in relation to changing dopamine levels.     

Recognition of emotion in facial expression by people with Prader-Willi syndrome

Background People with Prader–Willi syndrome (PWS) may have mild intellectual impairments but less is known about their social cognition. Most parents/carers report that people with PWS do not have normal peer relationships, although some have older or younger friends. Two specific aspects of social cognition are being able to recognise other people's emotion and to then respond appropriately. In a previous study, mothers/carers thought that 26% of children and 23% of adults with PWS would not respond to others' feelings. They also thought that 64% could recognise happiness, sadness, anger and fear and a further 30% could recognise happiness and sadness. However, reports of emotion recognition and response to emotion were partially dissociated. It was therefore decided to test facial emotion recognition directly. Method The participants were 58 people of all ages with PWS. They were shown a total of 20 faces, each depicting one of the six basic emotions and asked to say what they thought that person was feeling. The faces were shown one at a time in random order and each was accompanied by a reminder of the six basic emotions. Results This cohort of people with PWS correctly identified 55% of the different facial emotions. These included 90% of happy faces, 55% each of sad and surprised faces, 43% of disgusted faces, 40% of angry faces and 37% of fearful faces. Genetic subtype differences were found only in the predictors of recognition scores, not in the scores themselves. Selective impairment was found in fear recognition for those with PWS who had had a depressive illness and in anger recognition for those with PWS who had had a psychotic illness. Conclusions The inability to read facial expressions of emotion is a deficit in social cognition apparent in people with PWS. This may be a contributing factor in their difficulties with peer relationships.