Affect Recognition, Empathy, and Dysosmia After Traumatic Brain Injury

Disrupted topological organization of functional brain networks in traumatic axonal injury

Traumatic axonal injury (TAI) may result in the disruption of brain functional networks and is strongly associated with cognitive impairment. However, the neural mechanisms affecting the neurocognitive function after TAI remain to be elucidated. We collected the resting-state functional magnetic resonance imaging data from 28 patients with TAI and 28 matched healthy controls. An automated anatomical labeling atlas was used to construct a functional brain connectome. We utilized a graph theoretical approach to investigate the alterations in global and regional network topologies, and network-based statistics analysis was utilized to localize the connected networks more precisely. The current study revealed that patients with TAI and healthy controls both showed a typical small-world topology of the functional brain networks. However, patients with TAI exhibited a significantly lower local efficiency compared to healthy controls, whereas no significant difference emerged in other small-world properties (Cp, Lp, γ, λ, and σ) and global efficiency. Moreover, patients with TAI exhibited aberrant nodal centralities in some regions, including the frontal lobes, parietal lobes, caudate nucleus, and cerebellum bilaterally, and right olfactory cortex. The network-based statistics results showed alterations in the long-distance functional connections in the subnetwork in patients with TAI, involving these brain regions with significantly altered nodal centralities. These alterations suggest that brain networks of individuals with TAI present aberrant topological attributes that are associated with cognitive impairment, which could be potential biomarkers for predicting cognitive dysfunction and help understanding the neuropathological mechanisms in patients with TAI.

Olfactory Dysfunction Following Moderate to Severe Traumatic Brain Injury: A Systematic Review and Meta-Analysis

OBJECTIVE

Reports of smell loss following traumatic brain injury (TBI) are a well-documented but understudied phenomenon. Given the broad consequences of olfactory loss, we characterized psychophysical olfactory dysfunction in individuals with moderate to severe TBI using systematic review and meta-analytic methods.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) protocol, five databases (PubMed, EMBASE, Cochrane Library, Web of Science, Scopus) were reviewed for studies investigating olfactory dysfunction in persons with moderate to severe TBI. Of the 5,223 studies reviewed, 19 met our inclusion criteria for the systematic review and 11 met inclusion criteria for meta-analysis. We calculated effect sizes (Hedges' g) to characterize the degree of olfactory dysfunction between patients with moderate to severe TBI and controls.

RESULTS

A total of 951 moderate-severe TBI patients from 19 studies were included in the systematic review, which largely demonstrated poorer olfactory psychophysical performances in this patient population. Meta-analysis demonstrated a large effect size for olfactory dysfunction in moderate-severe TBI relative to healthy controls (g=-2.43, 95%CI: -3.16 < δ<-1.69). The magnitude of the effect was moderated by age and patient sex, with larger effect sizes associated with older age (following exclusion of a pediatric population) and larger compositions of women in the patient group.

CONCLUSION

Moderate to severe TBI is associated with prominent olfactory dysfunction. Significant research gaps remain regarding the mechanism, recovery and natural history of olfactory dysfunction following moderate to severe TBI, which has significant clinical implications for the identification and treatment for those with post-traumatic olfactory dysfunction.

Post-traumatic olfactory dysfunction: a scoping review of assessment and rehabilitation approaches

Post-traumatic Olfactory Dysfunction (PTOD) consists of a complete or partial loss of olfactory function that may occur after a traumatic brain injury (TBI). PTOD may be linked to some neuropsychiatric features, such as social, cognitive and executive dysfunction, as well as behavioral symptoms, especially when TBI involves the orbito-frontal cortex. The diagnosis of PTOD is based on medical history and clinical data and it is supported by psychometric tests (i.e., subjective tools) as well as electrophysiological and neuroimaging measures (i.e., objective methods). The assessment methods allow monitoring the changes in olfactory function over time and help to establish the right therapeutic and rehabilitative approach. In this context, the use of the olfactory training (OT), which is a non-pharmacological and non-invasive treatment option, could promote olfactory function through top-down (central) and bottom-up (peripheral) processes. To better manage patients with TBI, PTOD should be detected early and properly treated using the various therapeutic rehabilitative possibilities, both conventional and advanced, also taking into consideration the emerging neuromodulation approach.

Associations of Prior Head Injury With Olfaction in Older Adults: Results From the Atherosclerosis Risk in Communities (ARIC) Study

Importance

Traumatic brain injury has been associated with short-term olfactory dysfunction, but the association of number of prior head injuries and head injury severity with both subjective and objective long-term olfactory function is less clear.

Objective

To investigate the associations of prior head injury, number of prior head injuries, and head injury severity with subjective and psychophysical (objective) olfactory function in older adults and to examine concordance between subjective and objective olfactory function among individuals with and without head injury.

Design, Setting, and Participants

This prospective cohort study included 5951 participants who attended Atherosclerosis Risk in Communities (ARIC) Study visit 5 (2011 through 2013). Data analysis was performed between November 2021 and May 2022.

Exposures

Head injury was defined by self-report and International Classification of Diseases codes.

Main Outcomes and Measures

Self-reported subjective olfactory dysfunction was assessed by the question, "Do you suffer from smell loss or a significantly decreased sense of smell?" Objective olfactory performance was assessed using the 12-item Sniffin' Sticks odor identification test.

Results

Overall, the 5951 participants were a mean (SD) age of 75.6 (5.2) years, 3501 (58.8%) were female, 1356 (22.8%) were of Black race, and 1666 (28.0%) had a history of head injury. Participants with prior head injury were more likely than individuals without prior head injury to report subjective olfactory dysfunction (24% vs 20%; difference, 4%; 95% CI, 1% to 6%) and have objective anosmia (15% vs 13%; difference, 2%; 95% CI, 0.1% to 4%) but had lower concordance between subjective and objective assessment (72% vs 77%; difference, -5%; 95% CI, -8% to -3%). In logistic regression models adjusted for sociodemographics and medical comorbidities including cognitive status, participants with a history of prior head injury, particularly individuals with 2 or more prior head injuries and more severe head injuries, were more likely to self-report subjective olfactory dysfunction and were more likely to be found to have objective anosmia compared with participants with no history of head injury.

Conclusions and Relevance

Findings of this cohort study provide evidence supporting the association between head injury and olfactory dysfunction, particularly among individuals who experienced multiple prior head injuries and among individuals with more severe head injury. The findings also suggest that individuals with prior head injury were more likely to both under-self-report and over-self-report deficits compared with objective olfactory testing; therefore, it may be important to consider objective olfactory testing in this patient population.

Loss of smell in patients with traumatic brain injury is associated with neuropsychiatric behavioral alterations

OBJECTIVE

We sought to identify and correlate the severity of traumatic brain injuries (TBIs) associated with olfactory dysfunction with cognitive and behavioral profiles.

PARTICIPANTS AND SETTING

Patients with TBI undergoing treatment in a specialized neuro-rehabilitation hospital.

DESIGN

Prospective study.

MAIN MEASURES

Glasgow Coma Scale (GCS) at the time of injury and during posttraumatic amnesia. Motor functions were assessed with the Functional Instrument Measure and Disability Rating Scales. The Wechsler Adult Intelligence test was used for neuropsychologic assessment and the Neuropsychiatric Inventory was used to assess behavioral changes. The Barcelona Smell Test-24 was used to study subjective smell loss.

RESULTS

A total of 111 patients with TBI were enrolled (33 females; mean age 32.86 years); 38.73% exhibited smell loss. Patients with no olfactory impairment (OI) had worse TBIs than those with OI (GCS scores 5.65 and 7.74, respectively); no significant differences in cognitive behaviors, such as attention memory, visuoperception, and visuoconstruction, were observed. However, patients with TBI and olfactory dysfunction showed statistically significant alterations in neuropsychiatric behavioral performances such as feeding when compared with patients with TBI without smell loss.

CONCLUSION

Olfactory dysfunction in patients with a TBI correlates with altered neuropsychiatric behavioral performances such as feeding, sleeping, and motor behavior.

Effects of olfactory training on posttraumatic olfactory dysfunction: a systematic review and meta-analysis

BACKGROUND

Posttraumatic olfactory dysfunction is a clinical challenge due to refractory characteristics and limited therapeutic options. Olfactory training has been proved to be effective for olfactory dysfunction with varied etiologies. We pooled existing studies to evaluate the effects of olfactory training in patients with posttraumatic olfactory dysfunction.

METHODS

A systematic literature review using PubMed, Embase, Cochrane Library, and Web of Science was conducted to identify studies assessing olfactory change in patients with posttraumatic olfactory dysfunction after olfactory training.

RESULTS

Of the initial 812 abstracts reviewed, 13 full-text articles were included. Clinically significant results after olfactory training were defined as an improvement of threshold, discrimination, and identification (TDI) score ≥6 or University of Pennsylvania Smell Identification Test (UPSIT) score ≥4. Six studies were included in the meta-analysis, 36.31% (95% confidence interval [CI], 0.28 to 0.45) of posttraumatic patients would achieve clinically significant results after olfactory training with a mean increase of TDI score of 4.61.

CONCLUSION

Olfactory training might be a promising modality for the treatment of posttraumatic olfactory dysfunction. More high-quality studies with controls are needed to clarify the effect of olfactory training on total olfactory performance and subcomponents of olfaction.

The role of olfaction and sex-hormone status in empathy-related measures

Reports of a female advantage in empathy-related measures suggest a role for sex hormones, although the data are inconsistent. Studies also report similar sex differences in human olfactory perception. In rodents, olfaction is involved in detecting and integrating socially relevant information and is modulated by the brain actions of estrogens. We hypothesized that olfaction may untangle the mixed evidence on the relationship between sex hormones and empathy-related measures (cognitive and affective) in humans. To test this, we examined 60 healthy participants in three sex-hormone-status groups: free-cycling women tested in cycle phases with higher 17-β estradiol and progesterone, oral-contraceptive users (low estradiol and progesterone), and men. We assessed empathy-related measures, facial mimicry (from zygomaticus and corrugator muscle activity), and odor discrimination ability. In the empathy-related measures and facial mimicry, we did not find overall group effects or meaningful associations with salivary levels of estradiol, progesterone, or testosterone. Free-cycling women only outperformed men in the recognition of emotions from pictures of the eye region, but sex hormones were unrelated to emotion recognition performance. Oral contraceptive users showed higher scores in the affective empathy-related measure when viewing negative emotions, with no relation to hormone levels. Free-cycling women exhibited the strongest facial mimicry (viewing female, but not male protagonists), positively associated with progesterone. Finally, the groups differed in odor discrimination, with free-cycling women outperforming men. However, odor discrimination ability and empathy-related performance were not correlated. Our results support a role of sex hormones in odor perception and in empathy-related measures, to a certain extent. However, no common underlying mechanism was found.

The relationship between vocal affect recognition and psychosocial functioning for people with moderate to severe traumatic brain injury: a systematic review

The purpose of this review was to explore how vocal affect recognition deficits impact the psychosocial functioning of people with moderate to severe traumatic brain injury (TBI). A systematic review following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines was conducted, whereby six databases were searched, with additional hand searching of key journals also completed. The search identified 1847 records after duplicates were removed, and 1749 were excluded through title and abstract screening. After full text screening of 65 peer-reviewed articles published between January 1999 and August 2019, only five met inclusion criteria. The methodological quality of selected studies was assessed using the Mixed Methods Appraisal Tool (MMAT) Version 2018 with a fair level of agreement reached. A narrative synthesis of the results was completed, exploring vocal affect recognition and psychosocial functioning of people with moderate to severe TBI, including aspects of social cognition (i.e., empathy; Theory of Mind) and social behaviour. Results of the review were limited by a paucity of research in this area, a lack of high-level evidence, and wide variation in the outcome measures used. More rigorous study designs are required to establish more conclusive evidence regarding the degree and direction of the association between vocal affect recognition and aspects of psychosocial functioning. This review is registered with Prospero.

Negative Attribution Bias and Related Risk Factors After Brain Injury

OBJECTIVE

In participants with traumatic brain injury (TBI) and peer controls, examine (1) differences in negative attributions (interpret ambiguous behaviors negatively); (2) cognitive and emotional factors associated with negative attributions; and (3) negative attribution associations with anger responses, life satisfaction, and participation.

SETTING

Two TBI outpatient rehabilitation centers.

PARTICIPANTS

Participants with complicated mild to severe TBI (n = 105) and peer controls (n = 105).

DESIGN

Cross-sectional survey study.

MAIN MEASURES

Hypothetical scenarios describing ambiguous behaviors were used to assess situational anger and attributions of intent, hostility, and blame. Executive functioning, perspective taking, emotion perception and social inference, alexithymia, aggression, anxiety, depression, participation, and life satisfaction were also assessed.

RESULTS

Compared with peer controls, participants with TBI rated behaviors significantly more intentional, hostile, and blameworthy. Regression models explained a significant amount of attribution variance (25%-43%). Aggression was a significant predictor in all models; social inference was also a significant predictor of intent and hostility attributions. Negative attributions were associated with anger responses and lower life satisfaction.

CONCLUSION

People with TBI who have higher trait aggression and poor social inferencing skills may be prone to negative interpretations of people's ambiguous actions. Negative attributions and social inferencing skills should be considered when treating anger problems after TBI.

Apparently Minor Head Trauma Can Lead to Anosmia: A Case Report

We report the case of a 49-year-old female patient who suffered from anosmia following an apparently mild head trauma when bumping into a door at her home. She reported no other accompanying symptoms after the injury that day. Olfactory function was completely lost, which was noted the day after the trauma. Gustatory function remained normal. Magnetic resonance imaging indicated lesions/bleeding in the right frontal lobe and in the area of the olfactory sulcus/bulb. The present case indicates that in case of apparently mild head trauma with anosmia, an MRI scan of the head should be performed because of suspect brain damage. This case also points to the deeper question how to gauge severity of head trauma.

A sensorimotor control framework for understanding emotional communication and regulation

Our research team was asked to consider the relationship of the neuroscience of sensorimotor control to the language of emotions and feelings. Actions are the principal means for the communication of emotions and feelings in both humans and other animals, and the allostatic mechanisms controlling action also apply to the regulation of emotional states by the self and others. We consider how motor control of hierarchically organised, feedback-based, goal-directed action has evolved in humans, within a context of consciousness, appraisal and cultural learning, to serve emotions and feelings. In our linguistic analysis, we found that many emotion and feelings words could be assigned to stages in the sensorimotor learning process, but the assignment was often arbitrary. The embodied nature of emotional communication means that action words are frequently used, but that the meanings or senses of the word depend on its contextual use, just as the relationship of an action to an emotion is also contextually dependent.

Social communication following traumatic brain injury part I: State-of-the-art review of assessment tools

PURPOSE

The primary aim of this paper was to identify and describe current social communication assessment tools for adults with traumatic brain injury.

METHOD

We conducted a state-of-the-art review to identify and categorise the range of social communication assessment tools found in the assessment and treatment literature that revealed 42 measures that were coded according to characteristics related to assessment types, psychometrics, and implementation.

RESULT

Of the 42 assessments, 64% evaluated social cognition and the remaining 36% evaluated communication. Coding of implementation categories revealed that only 18/42 (43%) measures were ecologically grounded and 23/42 (55%) were available to clinicians by purchase or in the public domain. Only three measures incorporated questions or an assessment of the examinee's priorities or concerns.

CONCLUSION

A number of factors limit current social communication assessment. The lack of tools that objectively and reliably evaluate communication or social cognition in ecologically valid ways remains problematic. Of particular concern is the lack of prioritisation of the individual's communication values and needs. Recommendations include a call to focus research on the development of more contextual, standardised assessments, consider availability and feasibility when tools are being developed, and evaluate assessment processes as well as discrete tools.

The influence of head injury on olfactory and gustatory function

Head injury, particularly that resulting in brain injury, is a significant public health concern. For example, annual incidence rates of traumatic brain injury, a common consequence of head injury, range from 54 to 60 million people worldwide, including 2.2-3.6 million people whose trauma is moderate to severe. Trauma to the face and brain, including blast injuries common in modern warfare, can result in alterations in the ability to both smell and taste. In the case of smell, these include total loss of function (anosmia), decreased sensitivity (hyposmia), alterations in odor quality (dysosmia), and hallucination (phantosmia). Although taste dysfunction, i.e., altered perception of such basic taste-bud-mediated sensations as sweet, sour, bitter, salty, and savory (umami), can be similarly influenced by head trauma, the effects are typically more subtle and less studied. The present review provides an up-to-date assessment of what is known about the impact of head injury on quantitative measures of taste and smell function, including the influences of severity, type of injury, location of insults, prognosis, and approaches to therapy.

Perceived personality change after traumatic brain injury II: comparing participant and informant perspectives

OBJECTIVE

The objective of this paper was to correlate informant personality change (PC) judgements following moderate-severe traumatic brain injury with quantitative neurobehavioural measures and to contrast the neurobehavioural correlates of informant and participant judgements of PC.

PARTICIPANTS

Informant-participant pairs were recruited from a medico-legal clinic passing effort tests (N = 31) and a National Health Service clinic (N = 40).

MEASURES

Participants were assessed on Wechsler tests of general ability, tests of executive functioning (Zoo Map and Fluency) and emotional distress (Beck Depression Inventory-FastScreen, Hospital Anxiety and Depression Scale and State-Trait Anger Expression Inventory-II). Informants' expressed emotion towards participants was assessed with the family questionnaire. Both completed the DEX, the Frontal and Social Behavior Questionnaire and PC ratings.

RESULTS

The correlates of participant and informant ratings of participant PC partially overlapped. For example, participant self-reported PC was associated with self-reported dysexecutive symptoms and emotional distress. In contrast, informant report of participant PC was associated with lower perceived emotional recognition and empathy, informant report of dysexecutive symptoms and high informant expressed emotion.

CONCLUSIONS

It is argued that whilst researchers aim to exhaustively quantify specific neurobehavioural changes and their clusters, partially overlapping subsets of these changes evoke the PC judgements of participants and informants. The clinical implications of this are briefly considered.

Stroke of bad luck?

We hypothesized that distinct acute right hemisphere lesions disrupt separate components of valuation and emotional response to winning and losing money and of emotional empathy in observing a partner win or lose money. We measured skin conductance response (SCR) and ratings of emotions when acute right hemisphere stroke patients or healthy controls won or lost money in roulette, or when they watched a partner win or lose. Our results showed that percentage of damage after stroke to right anterior insula and frontal operculum negatively correlated with both SCR to winning and losing and difference between rating wins versus losses.

Social Cognitive Interventions in Neuropsychiatric Patients: A Meta-Analysis

Social cognitive deficits are common in neuropsychiatric disorders. Given the proximity of social cognition (SC) to everyday functioning, many intervention studies (including targeted, comprehensive, and broad-based approaches) have focussed on SC. The aim of this paper was to quantitatively meta-analyse the efficacy of SC interventions in adult neuropsychiatric patients. Databases Pubmed, PsycINFO, Web of Knowledge, and Embase were searched for controlled SC intervention studies published between 01-01-2003 and 01-01-2016. Forty-one studies, comprising 1,508 patients with schizophrenia, autism spectrum disorders, or acquired brain injury were included. Outcome measures evaluated emotion perception (EP), social perception (SP), Theory of Mind (ToM), and social functioning (SF). The meta-analyses showed that interventions were effective in improving SC (Cohen'sd=.71). Interventions targeting one specific SC function were found to be most effective (d=.89), followed by broad-based interventions, targeting non-SC domains in addition to SC (d=.65), and comprehensive interventions, that target multiple SC processes (d=.61). Targeted interventions were especially effective in improving EP and ToM. Comprehensive interventions were able to ameliorate EP, ToM, and SF. Broad-based interventions were especially effective in improving SF, but also showed effects on EP and ToM.

Sex Differences in Emotion Recognition and Emotional Inferencing Following Severe Traumatic Brain Injury

The primary objective of the current study was to determine if men and women with traumatic brain injury (TBI) differ in their emotion recognition and emotional inferencing abilities. In addition to overall accuracy, we explored whether differences were contingent upon the target emotion for each task, or upon high- and low-intensity facial and vocal emotion expressions. A total of 160 participants (116 men) with severe TBI completed three tasks – a task measuring facial emotion recognition (DANVA-Faces), vocal emotion recognition (DANVA-Voices) and one measuring emotional inferencing (emotional inference from stories test (EIST)). Results showed that women with TBI were significantly more accurate in their recognition of vocal emotion expressions and also for emotional inferencing. Further analyses of task performance showed that women were significantly better than men at recognising fearful facial expressions and also facial emotion expressions high in intensity. Women also displayed increased response accuracy for sad vocal expressions and low-intensity vocal emotion expressions. Analysis of the EIST task showed that women were more accurate than men at emotional inferencing in sad and fearful stories. A similar proportion of women and men with TBI were impaired (≥ 2 SDs when compared to normative means) at facial emotion perception, χ2 = 1.45, p = 0.228, but a larger proportion of men was impaired at vocal emotion recognition, χ2 = 7.13, p = 0.008, and emotional inferencing, χ2 = 7.51, p = 0.006.

Brain volume loss contributes to arousal and empathy dysregulation following severe traumatic brain injury

Severe traumatic brain injury (TBI) often leads to deficits in physiological arousal and empathy, which are thought to be linked. This study examined whether injury-related brain volume loss in key limbic system structures is associated with these deficits. Twenty-four adults with TBI and 24 matched Controls underwent MRI scans to establish grey matter volumes in the amygdala, thalamus, and hippocampus. EEG and skin conductance levels were recorded to index basal physiological arousal. Self-report emotional empathy levels were also assessed. The TBI group had reduced brain volumes, topographic alpha differences, and lower emotional empathy compared to Controls. Regional brain volumes were differentially correlated to arousal and self-report empathy. Importantly, lower volume in pertinent brain structures correlated with lower empathy, for participants with and without TBI. Overall we provide new insights into empathic processes after TBI and their relationship to brain volume loss.

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EEG alpha power and SCL provide a stable measure of arousal disturbance following severe traumatic brain injury.

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Diminished arousal was associated with reduced volume in the amygdala and thalamus.

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Lower affective empathy was associated with reduced volume in the amygdala and hippocampus.

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These relationships were found for participants with and without brain injury.

Patient's Loss of Empathy Is Associated With Caregiver Burden

Patients benefit from the presence of empathic caregivers (CGs). In this regard, empathy toward the patient is one of the clinical targets for improving patient outcomes. However, relatively little is known about the impact of patients' empathic responses on the CGs' burden. Among people living with Parkinson's disease (PwP), care partners play a major role. This study involved 28 spouse-patient couples. Empathy, stress burden, and mood disorders (such as anxiety and depression) were assessed over a 6-month period, before and after the reported intervention. Our observation points out that the improvement of patient empathy is necessary for a significant burden reduction among spouses caring for PwP.

Exploration of correlates of self-reported personality change after moderate-severe traumatic brain injury

OBJECTIVE

Individuals with traumatic brain injury (TBI) often express concern that their personality has changed. Factors generating that conclusion are rarely explored quantitatively. Accordingly, this study examines neurobehavioural correlates of self-reported personality change.

METHODS

Seventy-one participants and informants were interviewed M = 57.9 (SD = 46.9) months after a moderate-severe TBI. The degree of self-reported personality change was correlated with scores on measures of general cognitive functioning, executive functioning, olfaction, social-emotional behaviour, emotional distress and the Expressed Emotion close informants directed towards them.

RESULTS

As expected, self-reported personality change correlated with dysexecutive symptoms and depression. Although anosmia (a putative index of ventral frontal damage) correlated with reduced self-reported emotional recognition and empathy, against prediction, the latter measures did not correlate with self-reported personality change. Neither were the predicted positive correlations found between high Expressed Emotion (criticism and emotional over-involvement) and self-reported personality change.

DISCUSSION

These findings are discussed in the context of previous work. A need to replicate and extend the present findings is suggested. A strategy to further clarify the relationships perceived personality change have with (a) self-reported change in specific behaviours and (b) identity change is advocated. Implications for intervention are suggested.

Impaired Empathic Abilities among Patients with Complex Regional Pain Syndrome (Type I)

OBJECTIVE

The aims of this study were to evaluate differences in empathic abilities between patients with complex regional pain syndrome (CRPS) Type I and healthy control subjects (HCs) and to assess correlations between empathic abilities and multidimensional aspects of pain.

METHODS

Empathic ability was measured in 32 patients with CRPS Type I and in 36 HCs using the Interpersonal Reactivity Index (IRI). A comprehensive assessment of pain was conducted in the patient group using the West Haven-Yale Multidimensional Pain Inventory (WHYMPI). Psychiatric symptoms were assessed using the Beck Depression and Anxiety Inventories (BDI and BAI), and quality of life was evaluated using the WHO Quality of Life (WHOQOL-BREF) questionnaire.

RESULTS

Patients with CRPS showed impaired cognitive and emotional empathic abilities compared with HCs. Significantly lower levels of perspective taking and empathic concern and higher levels of personal distress on the IRI were exhibited by the patient group. Perspective taking and personal distress were associated with affective distress and poor quality of life in social contexts (BDI, BAI, and WHOQOL). However, empathic concern was positively correlated with pain severity and social support from others (WHYMPI).

CONCLUSION

A tendency toward self-oriented distress in social cognition was exhibited among patients with CRPS Type I. Impaired empathic ability was shown to have potentially negative effects on subjective emotional outcomes and social performance in the lives of patients. Interventions to improve emotional awareness and theory of mind would be beneficial for enhancing social functioning in patients with CRPS Type I.

Posttraumatic olfactory dysfunction

Impairment of smell may occur following injury to any portion of the olfactory tract, from nasal cavity to brain. A thorough understanding of the anatomy and pathophysiology combined with comprehensively obtained history, physical exam, olfactory testing, and neuroimaging may help to identify the mechanism of dysfunction and suggest possible treatments. Although most olfactory deficits are neuronal mediated and therefore currently unable to be corrected, promising technology may provide novel treatment options for those most affected. Until that day, patient counseling with compensatory strategies and reassurance is essential for the maintenance of safety and QoL in this unique and challenging patient population.

Congenital anosmia and emotion recognition: A case-control study

Patients with anosmia are not able to detect volatile chemicals signaling the presence of infectious and non-infectious environmental hazards, which typically elicit disgust and fear, respectively. Social animals may compensate a loss of olfaction by taking advantage of signals of threat that are produced by their conspecifics. Among humans and other primates, body postures and facial expressions are powerful cues conveying emotional information, including fear and disgust. The aim of the present study was to examine whether humans with agenesis of the olfactory bulb, a rare disorder characterized by congenital anosmia, would be more accurate in recognizing facial expressions of fear and disgust. A total of 90 participants with no history of mental disorder or traumatic brain injury were recruited, including 17 patients with congenital anosmia (10 men, mean age ± standard deviation: 36.5 ± 14.8 years), 34 patients with acquired anosmia (18 men, mean age ± standard deviation: 57.2 ± 11.8 years) and 39 healthy subjects (22 men, mean age ± standard deviation: 36.7 ± 13.2 years). For each patient with congenital anosmia, the agenesis of the olfactory bulb was ascertained through magnetic resonance imaging. Emotion recognition abilities were examined with a dynamic paradigm in which a morphing technique allowed displaying emotional facial expressions increasing in intensity over time. Adjusting for age, education, depression and anxiety, patients with congenital anosmia required similar levels of intensity to correctly recognize fear and disgust than healthy subjects while they displayed decreased error rates for both fear (mean difference [95% confidence interval] = -28.3% [-46.3%, -10.2%], P = 0.003) and disgust (mean difference [95% confidence interval] = -15.8% [-31.5%, -0.2%], P = 0.048). Furthermore, among patients with acquired anosmia, there was a negative correlation between duration of anosmia and the rate of errors for fearful (Spearman's ρ = -0.531, P= 0.001) or disgust (Spearman's ρ = -0.719, P < 0.001) faces recognition. No significant difference was observed for the other primary emotions. Overall, these results suggest that patients with congenital anosmia and long-lasting acquired anosmia may compensate their inability to detect environmental hazards through olfaction by an increased ability to detect fear or disgust as facially expressed by others.

Developing an Alternative Chinese Version of the Interpersonal Reactivity Index for Normal Population and Patients with Schizophrenia in Taiwan

The Interpersonal Reactivity Index (IRI) is a multidimensional individual-difference measure of empathy. The original IRI has been used in many studies to assess both normal and clinical samples. Because of its wide availability and convenience of use, the IRI has been translated into several languages. In Taiwan, the IRI was translated into traditional Chinese as a Chinese Version of the Interpersonal Reactivity Index (C-IRI) in 1987. Because the C-IRI was developed over 26 years ago and recent studies have shown some unsatisfactory psychometric properties on the C-IRI, there was a need to develop an alternative to the C-IRI and verify its psychometric properties again. In this study, we assessed the psychometric properties of an alternative C-IRI by administering it to 516 college students, 35 community residents and 70 schizophrenic patients, all of whom are adults. Exploratory factor analyses revealed a four-factor structure: Fantasy, Perspective Taking, Empathy and Personal Distress. Acceptable convergent and divergent validity supported the construct validity of the alternative C-IRI. Evidence was also found for its discriminant validity between patients with schizophrenia and normal controls on the Empathy subscale and Affective Empathy, while the full scale and its factors demonstrated good internal consistency and test–retest reliability. In the future, the alternative C-IRI should be validated with adolescent or elderly samples, and different clinical samples.

Traumatic brain injury and olfaction: a systematic review

Traumatic brain injury (TBI) is a common condition that is often complicated by neuropsychiatric sequelae that can have major impacts on function and quality of life. An alteration in the sense of smell is recognized as a relatively common complication of TBI; however in clinical practice, this complication may not be sought or adequately characterized. We conducted a systematic review of studies concerned with olfactory functioning following TBI. Our predetermined criteria led to the identification of 25 studies published in English, which we examined in detail. We have tabulated the data from these studies in eight separate tables, beginning with Table 1, which highlights each study’s key findings, and we provide a summary/synthesis of the findings in the accompanying results and discussion sections. Despite widely differing methodologies, the studies attest to a high frequency of post-TBI olfactory dysfunction and indicate that its presence can serve as a potential marker of additional structural or functional morbidities.

Inability to empathize: brain lesions that disrupt sharing and understanding another's emotions

Emotional empathy--the ability to recognize, share in, and make inferences about another person's emotional state--is critical for all social interactions. The neural mechanisms underlying emotional empathy have been widely studied with functional imaging of healthy participants. However, functional imaging studies reveal correlations between areas of activation and performance of a task, so that they can only reveal areas engaged in a task, rather than areas of the brain that are critical for the task. Lesion studies complement functional imaging, to identify areas necessary for a task. Impairments in emotional empathy have been mostly studied in neurological diseases with fairly diffuse injury, such as traumatic brain injury, autism and dementia. The classic 'focal lesion' is stroke. There have been scattered studies of patients with impaired empathy after stroke and other focal injury, but these studies have included small numbers of patients. This review will bring together data from these studies, to complement evidence from functional imaging. Here I review how focal lesions affect emotional empathy. I will show how lesion studies contribute to the understanding of the cognitive and neural mechanisms underlying emotional empathy, and how they contribute to the management of patients with impaired emotional empathy.

Acute lesions that impair affective empathy

Functional imaging studies of healthy participants and previous lesion studies have provided evidence that empathy involves dissociable cognitive functions that rely on at least partially distinct neural networks that can be individually impaired by brain damage. These studies converge in support of the proposal that affective empathy--making inferences about how another person feels--engages at least the following areas: prefrontal cortex, orbitofrontal gyrus, anterior insula, anterior cingulate cortex, temporal pole, amygdala and temporoparietal junction. We hypothesized that right-sided lesions to any one of these structures, except temporoparietal junction, would cause impaired affective empathy (whereas bilateral damage to temporoparietal junction would be required to disrupt empathy). We studied 27 patients with acute right hemisphere ischaemic stroke and 24 neurologically intact inpatients on a test of affective empathy. Acute impairment of affective empathy was associated with infarcts in the hypothesized network, particularly temporal pole and anterior insula. All patients with impaired affective empathy were also impaired in comprehension of affective prosody, but many patients with impairments in prosodic comprehension had spared affective empathy. Patients with impaired affective empathy were older, but showed no difference in performance on tests of hemispatial neglect, volume of infarct or sex distribution compared with patients with intact affective empathy.