Identifying Consciousness in Other Creatures: Three Initial Steps

Identifying consciousness in other creatures, be they animals or exotic creatures that have yet to be discovered, remains a great scientific challenge. We delineate the first three steps that we think are necessary for identifying consciousness in other creatures. Step 1 is to define the particular kind of consciousness in which one is interested. Step 2 is to identify, in humans, the key differences between the brain processes that are associated with consciousness and the brain processes that are not associated with consciousness. For Step 2, to identify these differences, we focus on passive frame theory. Step 3 concerns how the insights derived from consciousness research on humans (e.g., concerning these differences) can be generalized to other creatures. We discuss the significance of examining how consciousness was fashioned by the process of evolution, a process that could be happenstance and replete with incessant tinkering, yielding adaptations that can be suboptimal and counterintuitive, far different in nature from our efficiently designed robotic systems. We conclude that the more that is understood about the differences between conscious processing and unconscious processing in humans, the easier it will be to identify consciousness in other creatures.

The orbitofrontal cortex: A goal-directed cognitive map framework for social and non-social behaviors

The orbitofrontal cortex (OFC) is regarded as one of the core brain areas in a variety of value-based behaviors. Over the past two decades, tremendous knowledge about the OFC function was gained from studying the behaviors of single subjects. As a result, our previous understanding of the OFC's function of encoding decision variables, such as the value and identity of choices, has evolved to the idea that the OFC encodes a more complex representation of the task space as a cognitive map. Accumulating evidence also indicates that the OFC importantly contributes to behaviors in social contexts, especially those involved in cooperative interactions. However, it remains elusive how exactly OFC neurons contribute to social functions and how non-social and social behaviors are related to one another in the computations performed by OFC neurons. In this review, we aim to provide an integrated view of the OFC function across both social and non-social behavioral contexts. We propose that seemingly complex functions of the OFC may be explained by its role in providing a goal-directed cognitive map to guide a wide array of adaptive reward-based behaviors in both social and non-social domains.

Towards a pluralistic neurobiological understanding of consciousness

Theories of consciousness are often based on the assumption that a single, unified neurobiological account will explain different types of conscious awareness. However, recent findings show that, even within a single modality such as conscious visual perception, the anatomical location, timing, and information flow of neural activity related to conscious awareness vary depending on both external and internal factors. This suggests that the search for generic neural correlates of consciousness may not be fruitful. I argue that consciousness science requires a more pluralistic approach and propose a new framework: joint determinant theory (JDT). This theory may be capable of accommodating different brain circuit mechanisms for conscious contents as varied as percepts, wills, memories, emotions, and thoughts, as well as their integrated experience.

Social and nonsocial cognition: Are they linked? A study on patients with moderate-to-severe traumatic brain injury

OBJECTIVES

The first aim was to study the relationship between Social Cognition (SC) and nonsocial Cognition (n-SC) measures in a group of patients with moderate or severe traumatic brain injury (TBI) to assess the dependence or independence of both types of cognition. The second aim was to explore the relationships between SC measures and generate a model based on the results of these relationships.

METHODS AND PROCEDURES

Forty-three subacute patients with TBI were included in the study. They were administered a SC battery and n-SC battery. SC battery included the following measures: International Affective Picture System (IAPS); Facial Expressions of Emotion-Stimuli Test (FEEST); Moving Shapes Paradigm (MSP); Reading the Mind in the Eyes Test- Revised Version (RMET); Social Decision Making Task (SDMT). n-SC battery included Digit Span Forwards and Backwards; Trail Making Test (Part A); Rey's Auditory Verbal Learning Test; Letter-Number Sequencing; and verbal fluency test (PMR).

RESULTS

FEEST, MSP and RMET were related to n-SC measures. The exploratory factor analysis shows a two-factor SC structure: Factor 1: Emotional recognition and mentalization (FEEST, MSP and RMET) and Factor 2: Acquisition and contextualization (IAPS and SDMT).

CONCLUSION

The performance of subjects with moderate-to-severe TBI in the SC measures is related, at least partially, by the performance in the n-SC measures. Our SC model shows a two-factor structure characterized by a first factor that brings together SC measures that are highly related to n-SC domains and a second factor that brings together measures whose performance is not influenced by n-SC domains.

Metabolic Syndrome and Cognitive Function in Midlife

OBJECTIVE

Metabolic syndrome (MetS) is a cluster of cardiovascular risk factors associated with cognitive decline. We investigated the relationship between MetS and cognition in middle-aged adults. We hypothesized that higher numbers of MetS components will relate to poorer performance on executive function (EF) tasks as frontal lobe regions critical to EF are particularly vulnerable to cardiovascular disease.

METHODS

197 adults (ages 40-60) participated. MetS was evaluated using established criteria. Composite scores for cognitive domains were computed as follows: Global cognitive function (subtests from the Wechsler Abbreviated Scale of Intelligence, 2nd Edition), EF (Stroop Color Word, Digit Span Backward, and Trails A and B), and memory (California Verbal Learning Test, 2 Edition).

RESULTS

Higher number of MetS components was related to weaker EF-F(4, 191) = 3.94, p = .004, MetS components ß = -.14, p = .044. A similar relationship was detected for tests of memory-F(4, 192) = 7.86, p < .001, MetS components ß = -.15, p = .032. Diagnosis of MetS was not significantly associated with EF domain score (ß = -.05, p = .506) but was significantly associated with memory scores-F(4, 189) = 8.81, p < .001, MetS diagnosis ß = -.19, p = .006.

CONCLUSIONS

Our findings support prior research linking MetS components at midlife to executive dysfunction and demonstrate that MetS, and its components are also associated with poorer memory function. This suggests that cognitive vulnerability can be detected at midlife. Interventions for MetS at midlife could alter cognitive outcomes.

Therapeutic potential of intranasal photobiomodulation therapy for neurological and neuropsychiatric disorders: a narrative review

The application of photobiomodulation therapy (PBMT) for neuronal stimulation is studied in different animal models and in humans, and has shown to improve cerebral metabolic activity and blood flow, and provide neuroprotection via anti-inflammatory and antioxidant pathways. Recently, intranasal PBMT (i-PBMT) has become an attractive and potential method for the treatment of brain conditions. Herein, we provide a summary of different intranasal light delivery approaches including a nostril-based portable method and implanted deep-nasal methods for the effective systemic or direct irradiation of the brain. Nostril-based i-PBMT devices are available, using either lasers or light emitting diodes (LEDs), and can be applied either alone or in combination to transcranial devices (the latter applied directly to the scalp) to treat a wide range of brain conditions such as mild cognitive impairment, Alzheimer's disease, Parkinson's disease, cerebrovascular diseases, depression and anxiety as well as insomnia. Evidence shows that nostril-based i-PBMT improves blood rheology and cerebral blood flow, so that, without needing to puncture blood vessels, i-PBMT may have equivalent results to a peripheral intravenous laser irradiation procedure. Up to now, no studies were conducted to implant PBMT light sources deep within the nose in a clinical setting, but simulation studies suggest that deep-nasal PBMT via cribriform plate and sphenoid sinus might be an effective method to deliver light to the ventromedial part of the prefrontal and orbitofrontal cortex. Home-based i-PBMT, using inexpensive LED applicators, has potential as a novel approach for neurorehabilitation; comparative studies also testing sham, and transcranial PBMT are warranted.

Psychosocial impairment following mild blast-induced traumatic brain injury in rats

Traumatic brain injury (TBI) is associated with increased risk for mental health disorders, impacting post-injury quality of life and societal reintegration. TBI is also associated with deficits in psychosocial processing, defined as the cognitive integration of social and emotional behaviors, however little is known about how these deficits manifest and their contributions to post-TBI mental health. In this pre-clinical investigation using rats, a single mild blast TBI (mbTBI) induced impairment of psychosocial processing in the absence of confounding physical polytrauma, post-injury motor deficits, affective abnormalities, or deficits in non-social behavior. Impairment severity correlated with acute upregulations of a known oxidative stress metabolite, 3-hydroxypropylmercapturic acid (3-HPMA), in urine. Resting state fMRI alterations in the acute post-injury period implicated key brain regions known to regulate psychosocial behavior, including orbitofrontal cortex (OFC), which is congruent with our previous report of elevated acrolein, a marker of neurotrauma and 3-HPMA precursor, in this region following mbTBI. OFC of mbTBI-exposed rats demonstrated elevated mRNA expression of metabotropic glutamate receptors 1 and 5 (mGluR1/5) and injection of mGluR1/5-selective agonist in OFC of uninjured rats approximated mbTBI-induced psychosocial processing impairment, demonstrating a novel role for OFC in this psychosocial behavior. Furthermore, OFC may serve as a hotspot for TBI-induced disruption of psychosocial processing and subsequent mental health disorders.

Unravelling moral cognition in acquired brain injury: a scoping review

Background:

Acquired brain injury (ABI) is accompanied by impairments in social, emotional, cognitive and behavioural skills and highly prevalent in the population. Social and emotional skills are crucial for moral cognition, but the extent to which moral cognition contributes to social competence deficits in people with ABI is largely unclear.

Method:

To provide more insight on this topic, we conducted a scoping review according to the PRISMA guidelines. After screening 1269 articles that we obtained via PubMed and Scopus, we found 27 articles on moral cognition in ABI.

Results:

We encountered four important topics across these studies which include traumatic brain injury (TBI) versus non-TBI, the influence of the different approaches used to measure moral cognition in ABI, the role of age of onset and the role of location of the injury. Overall, evidence suggests that the earlier the brain damage occurred, the more this leads to impairments in moral cognitive functioning. The location of the injury furthermore seems to differentially affect the way impairments are manifested. Finally, we found that the use of different measurement approaches can heavily influence the interpretation of the impairment.

Conclusion:

We conclude that impairments in moral cognition in people with ABI are derived from a complex interplay between the age of onset, the location and the approach used to index moral cognition.

Role of BDNF in the development of an OFC-amygdala circuit regulating sociability in mouse and human

Social deficits are common in many psychiatric disorders. However, due to inadequate tools for manipulating circuit activity in humans and unspecific paradigms for modeling social behaviors in rodents, our understanding of the molecular and circuit mechanisms mediating social behaviors remains relatively limited. Using human functional neuroimaging and rodent fiber photometry, we identified a mOFC-BLA projection that modulates social approach behavior and influences susceptibility to social anxiety. In humans and knock-in mice with a loss of function BDNF SNP (Val66Met), the functionality of this circuit was altered, resulting in social behavioral changes in human and mice. We further showed that the development of this circuit is disrupted in BDNF Met carriers due to insufficient BDNF bioavailability, specifically during a peri-adolescent timeframe. These findings define one mechanism by which social anxiety may stem from altered maturation of orbitofronto-amygdala projections and identify a developmental window in which BDNF-based interventions may have therapeutic potential.

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.

Anosognosia for theory of mind deficits: A single case study and a review of the literature

Being aware of one's own ability to interact socially is crucial to everyday life. After a brain injury, patients may lose their capacity to understand others' intentions and beliefs, that is, the Theory of Mind (ToM). To date, the debate on the association between ToM and other cognitive deficits (in particular executive functions and behavioural disorders) remains open and data regarding awareness of ToM deficits are meagre. By means of an ad-hoc neuropsychological battery of tests, we report on a patient who suffers from ToM deficits and is not aware of these disorders, although aware of his other symptoms. The study is accompanied by a review of the literature (PRISMA guidelines) demonstrating that ToM deficits are independent of executive functions. Furthermore, an advanced lesion analysis including tractography was executed. The results indicate that: i) ToM deficits can be specific and independent of other cognitive symptoms; ii) unawareness may be specific for ToM impairment and not involve other disorders and iii) the medial structures of the limbic, monitoring and attentional systems may be involved in anosognosia for ToM impairment.

Theory of Mind Impairments Highlighted With an Ecological Performance-Based Test Indicate Behavioral Executive Deficits in Traumatic Brain Injury

Background: In view of the recent literature, the negative impact of traumatic brain injury (TBI) on social cognition remains a debated issue. On one hand, a considerable number of studies reported significant impairments in emotion recognition, empathy, moral reasoning, social problem solving, and mentalizing or theory of mind (ToM) abilities in patients with TBI. On the other hand, the ecological validity of social cognition tasks is still a matter of concern and debate for clinicians and researchers.

Objectives: The objectives of the present study were 2-fold: (1) to assess social cognition in TBI with an ecological performance-based test which focuses on ToM ability, and (2) to study the relationship between performances on this task and behavioral disorders. To this end, 47 patients with moderate to severe TBI in the chronic stage were assessed with a ToM task, the Movie for the Assessment of Social Cognition (MASC), a film displaying social interactions in natural settings and asking for an evaluation of the emotions, thoughts, and intentions of the characters. Behavioral disorders were assessed with the Behavioral Dysexecutive Syndrome Inventory (BDSI), a structured interview of an informant in assessing changes compared with previous behavior in 12 domains.

Results: Patients were significantly less accurate in mental state attribution than a demographically matched group of 38 healthy control subjects. Significant others of patients also reported more behavioral executive problems than controls' relatives on most of the domains of the BDSI. In addition, social cognition performance in the MASC was significantly correlated with behavioral dysexecutive problems rated by proxies on the BDSI.

Conclusions: This study is the first to find association between impairments in mentalizing abilities in the MASC and behavioral impairments in patients with TBI, confirming the added value of this ecological task and that the recognition of social signals is a key element for adequate behavioral functioning.

Gender and Hemispheric Asymmetries in Acquired Sociopathy

The emergence of enduring antisocial personality changes in previously normal individuals, or "acquired sociopathy," has consistently been reported in patients with bilateral injuries of the ventromedial prefrontal cortex. Over the past three decades, cases of acquired sociopathy with (a) bilateral or (b) unilateral sparing of the ventromedial prefrontal cortex have been reported. These cases indicate that at least in a few individuals (a') neural structures beyond the ventromedial prefrontal cortex are also critical for normal social behavior, and (b') the neural underpinnings of social cognition may be lateralized to one cerebral hemisphere. Moreover, researchers have presented evidence that lesion laterality and gender may interact in the production of acquired sociopathy. In the present review, we carried out a comprehensive literature survey seeking possible interactions between gender and hemispheric asymmetry in acquired sociopathy. We found 85 cases of acquired sociopathy due to bilateral (N = 48) and unilateral (N = 37) hemispheric injuries. A significant association between acquired sociopathy and right hemisphere damage was found in men, whereas lesions were bilateral in most women with acquired sociopathy. The present survey shows that: (i) the number of well-documented single-cases of acquired sociopathy is surprisingly small given the length of the historical record; (ii) acquired sociopathy was significantly more frequent in men after an injury of the right or of both cerebral hemispheres; and (iii) in most women who developed acquired sociopathy the injuries affected both cerebral hemispheres. These findings may be especially valuable to neuroscientists and to functional neurosurgeons in particular for the planning of tumor resections as well as for the choice of the best targets for therapeutic neuromodulation.

Determinants of social behavior deficits and recovery after pediatric traumatic brain injury

Traumatic brain injury (TBI) during early childhood is associated with a particularly high risk of developing social behavior impairments, including deficits in social cognition that manifest as reduced social interactions, with profound consequences for the individuals' quality of life. A number of pre-injury, post-injury, and injury-related factors have been identified or hypothesized to determine the extent of social behavior problems after childhood TBI. These include variables associated with the individual themselves (e.g. age, genetics, the injury severity, and extent of white matter damage), proximal environmental factors (e.g. family functioning, parental mental health), and more distal environmental factors (e.g. socioeconomic status, access to resources). In this review, we synthesize the available evidence demonstrating which of these determinants influence risk versus resilience to social behavior deficits after pediatric TBI, drawing upon the available clinical and preclinical literature. Injury-related pathology in neuroanatomical regions associated with social cognition and behaviors will also be described, with a focus on findings from magnetic resonance imaging and diffusion tensor imaging. Finally, study limitations and suggested future directions are highlighted. In summary, while no single variable can alone accurately predict the manifestation of social behavior problems after TBI during early childhood, an increased understanding of how both injury and environmental factors can influence social outcomes provides a useful framework for the development of more effective rehabilitation strategies aiming to optimize recovery for young brain-injured patients.

Face cells in orbitofrontal cortex represent social categories

Perceiving social and emotional information from faces is a critical primate skill. For this purpose, primates evolved dedicated cortical architecture, especially in occipitotemporal areas, utilizing face-selective cells. Less understood face-selective neurons are present in the orbitofrontal cortex (OFC) and are our object of study. We examined 179 face-selective cells in the lateral sulcus of the OFC by characterizing their responses to a rich set of photographs of conspecific faces varying in age, gender, and facial expression. Principal component analysis and unsupervised cluster analysis of stimulus space both revealed that face cells encode face dimensions for social categories and emotions. Categories represented strongly were facial expressions (grin and threat versus lip smack), juvenile, and female monkeys. Cluster analyses of a control population of nearby cells lacking face selectivity did not categorize face stimuli in a meaningful way, suggesting that only face-selective cells directly support face categorization in OFC. Time course analyses of face cell activity from stimulus onset showed that faces were discriminated from nonfaces early, followed by within-face categorization for social and emotion content (i.e., young and facial expression). Face cells revealed no response to acoustic stimuli such as vocalizations and were poorly modulated by vocalizations added to faces. Neuronal responses remained stable when paired with positive or negative reinforcement, implying that face cells encode social information but not learned reward value associated to faces. Overall, our results shed light on a substantial role of the OFC in the characterizations of facial information bearing on social and emotional behavior.

Theory of Mind after Severe Acquired Brain Injury: Clues for Interpretation

Background. Recently, increased interest has been shown in Theory of Mind (ToM) abilities of individuals with severe acquired brain injury (sABI). ToM impairment following sABI can be associated with altered executive functioning and/or with difficulty in decoding and elaborating emotions. Two main theoretical models have been proposed to explain the mechanisms underlying ToM in the general population: Theory Theory and Simulation Theory. This review presents and discusses the literature on ToM abilities in individuals with sABI by examining whether they sustain the applicability of the Theory Theory and/or Simulation Theory to account for ToM deficits in this clinical population. We found 32 papers that are directly aimed at investigating ToM in sABI. Results did not show the univocal predominance of one model with respect to the other in explaining ToM deficits in sABI. We hypothesised that ToM processes could be explained by coinvolvement of the two models, i.e., according to personal experience, cognitive features, or the emotional resources of the persons with sABI.

Human lesion studies of ventromedial prefrontal cortex

Studies of neurological patients with focal lesions involving ventromedial prefrontal cortex (vmPFC) have demonstrated a critical role for this brain area in various aspects of cognition, emotion, and behavior. In this article, we review the key themes, methods, and findings from neuropsychological research on vmPFC lesion patients. Early case studies demonstrated profound disruptions in personality and behavior following vmPFC damage, including blunted affect, poor decision-making, and inappropriate social behavior. Subsequent laboratory investigations with groups of vmPFC lesion patients have revealed deficits in a host of interrelated functions, such as value-based decision-making, future and counterfactual thinking, physiological arousal to emotional stimuli, emotion recognition, empathy, moral judgment, and memory confabulation. The compendium of findings described here demonstrates that vmPFC is crucial for diverse aspects of adaptive function.

Rehabilitation of emergent awareness of errors post traumatic brain injury: A pilot intervention

Impaired awareness of errors is common following traumatic brain injury (TBI) and can be a barrier to successful rehabilitation. The objective of this study was to develop and evaluate a computer-based intervention programme aimed at improving error awareness in individuals with TBI. A further aim was to explore its effects on metacognitive awareness and variability of performance. Participants were 11 individuals with TBI and impaired error awareness who performed a sustained attention task twice-weekly for four weeks. The intervention consisted of audio-visual feedback-on-errors during the sustained attention task. Six participants received audio-visual feedback-on-error, five did not receive feedback. Emergent and metacognitive awareness were measured pre- and post-intervention. Between-groups comparisons of emergent awareness from pre- to post-intervention showed that audio-visual feedback-on-error improved emergent awareness compared to no feedback-on-error. Some changes in metacognitive awareness of executive behaviours as a result of feedback were observed. Audio-visual feedback-on-error improved emergent awareness in individuals with TBI following a four-week/eight-session intervention. This improvement was not observed in the no-feedback group. This pilot intervention is not a stand-alone treatment but it has potential to be usefully incorporated into cognitive or clinical rehabilitation programmes to improve emergent awareness.

Social brain circuitry and social cognition in infants born preterm

Preterm birth is associated with an increased risk of adverse neurologic, psychiatric, and cognitive outcomes. The brain circuits involved in processing social information are critical to all of these domains, but little work has been done to examine whether and how these circuits may be especially sensitive to prematurity. This paper contains a brief summary of some of the cognitive, psychiatric, and social outcomes associated with prematurity, followed by a description of findings from the modest body of research into social-cognitive development in infants and children born preterm. Next, findings from studies of structural and functional brain development in infants born preterm are reviewed, with an eye toward the distinctive role of the brain circuits implicated in social functioning. The goal of this review is to investigate the extent to which the putative "social brain" may have particular developmental susceptibilities to the insults associated with preterm birth, and the role of early social-cognitive development in later neurodevelopmental outcomes. Much work has been done to characterize neurobehavioral outcomes in the preterm population, but future research must incorporate both brain and behavioral measures to identify early biomarkers linked to later emerging social-cognitive clinical impairment in order to guide effective, targeted intervention.

Altered olfactory processing and increased insula activity in patients with obsessive-compulsive disorder: An fMRI study

Obsessive-compulsive disorder (OCD) patients show increased insula activation to disgust-inducing images compared to healthy controls (HC). We explored whether this disgust reactivity was also present in the olfactory domain by conducting the first fMRI study of olfaction in OCD. Neural activation in response to pleasant and unpleasant odors (vs. unscented air) was investigated in 15 OCD and 15 HC participants using fMRI. OCD participants (vs. HC) had increased left anterior insula activation to unpleasant odors (vs. unscented air), which positively correlated with their disgust sensitivity and ratings of the unpleasantness and intensity of those odors. OCD participants (vs. HC) showed increased activation of caudate nucleus and left anterior and posterior insula to pleasant odors (vs. unscented air), which positively correlated with their OCD symptom severity, trait anxiety, frequency of feeling disgust, and odor intensity ratings. OCD participants had increased anterior insula activation to both pleasant and unpleasant odors, which correlated with their OCD symptoms, anxiety, disgust sensitivity, and frequency of feeling disgust. OCD patients might have a negative cognitive bias and experience all stimuli, regardless of valence, as being more unpleasant than healthy people. These findings further elucidate the neural underpinnings of OCD and may contribute to more effective treatments.

The development of a measure of social cognition following acquired brain injury

Deficits in social cognition following acquired brain injury (ABI) have been found to be both prevalent and disabling. Despite this, relatively little attention has been given to identifying the characteristics of such deficits in a systematic way. We describe the development of self and informant versions of a new questionnaire designed to measure the changes in social cognition that may occur following ABI, the Brain Injury Rehabilitation Trust (BIRT) Social Cognition Questionnaire (BSCQ). Seventy-two participants (Mean age  = 36 years, SD = 12), with different forms of ABI (76% traumatic brain injury, 8% cerebrovascular accident, 15% other) and who were on average 20 months post-injury (SD = 16), took part in the study. The measure demonstrates excellent psychometric properties, including high test-retest (.94) and split-half (.92) reliability, high internal consistency (Cronbach's alpha = .92), and good concurrent validity. The questionnaire measures characteristics that are distinguishable from measures of cognitive ability. There was moderate overlap between self-report and informant versions of the questionnaire (r = .50), but the informant version had the strongest predictive value of outcome, measured with the Mayo-Portland Adaptability Inventory III, one year later. The potential uses of the measure in relation to theory and practice are discussed. The results suggest that the BSCQ is a useful screening tool for those with ABI.

Frontal Lobe Contusion in Mice Chronically Impairs Prefrontal-Dependent Behavior

Traumatic brain injury (TBI) is a major cause of chronic disability in the world. Moderate to severe TBI often results in damage to the frontal lobe region and leads to cognitive, emotional, and social behavioral sequelae that negatively affect quality of life. More specifically, TBI patients often develop persistent deficits in social behavior, anxiety, and executive functions such as attention, mental flexibility, and task switching. These deficits are intrinsically associated with prefrontal cortex (PFC) functionality. Currently, there is a lack of analogous, behaviorally characterized TBI models for investigating frontal lobe injuries despite the prevalence of focal contusions to the frontal lobe in TBI patients. We used the controlled cortical impact (CCI) model in mice to generate a frontal lobe contusion and studied behavioral changes associated with PFC function. We found that unilateral frontal lobe contusion in mice produced long-term impairments to social recognition and reversal learning while having only a minor effect on anxiety and completely sparing rule shifting and hippocampal-dependent behavior.

Role of Reversal Learning Impairment in Social Disinhibition following Severe Traumatic Brain Injury

OBJECTIVES

The current study aimed to determine whether reversal learning impairments and feedback-related negativity (FRN), reflecting reward prediction error signals generated by negative feedback during the reversal learning tasks, were associated with social disinhibition in a group of participants with traumatic brain injury (TBI).

METHODS

Number of reversal errors on a social and a non-social reversal learning task and FRN were examined for 21 participants with TBI and 21 control participants matched for age. Participants with TBI were also divided into low and high disinhibition groups based on rated videotaped interviews.

RESULTS

Participants with TBI made more reversal errors and produced smaller amplitude FRNs than controls. Furthermore, participants with TBI high on social disinhibition made more reversal errors on the social reversal learning task than did those low on social disinhibition. FRN amplitude was not related to disinhibition.

CONCLUSIONS

These results suggest that impairment in the ability to update behavior when social reinforcement contingencies change plays a role in social disinhibition after TBI. Furthermore, the social reversal learning task used in this study may be a useful neuropsychological tool for detecting susceptibility to acquired social disinhibition following TBI. Finally, that the FRN amplitude was not associated with social disinhibition suggests that reward prediction error signals are not critical for behavioral adaptation in the social domain.

Homing in on consciousness in the nervous system: An action-based synthesis

What is the primary function of consciousness in the nervous system? The answer to this question remains enigmatic, not so much because of a lack of relevant data, but because of the lack of a conceptual framework with which to interpret the data. To this end, we have developed Passive Frame Theory, an internally coherent framework that, from an action-based perspective, synthesizes empirically supported hypotheses from diverse fields of investigation. The theory proposes that the primary function of consciousness is well-circumscribed, serving the somatic nervous system. For this system, consciousness serves as a frame that constrains and directs skeletal muscle output, thereby yielding adaptive behavior. The mechanism by which consciousness achieves this is more counterintuitive, passive, and "low level" than the kinds of functions that theorists have previously attributed to consciousness. Passive frame theory begins to illuminate (a) what consciousness contributes to nervous function, (b) how consciousness achieves this function, and (c) the neuroanatomical substrates of conscious processes. Our untraditional, action-based perspective focuses on olfaction instead of on vision and is descriptive (describing the products of nature as they evolved to be) rather than normative (construing processes in terms of how they should function). Passive frame theory begins to isolate the neuroanatomical, cognitive-mechanistic, and representational (e.g., conscious contents) processes associated with consciousness.

Response to hypothetical social scenarios in individuals with traumatic brain injury who present inappropriate social behavior: a preliminary report

BACKGROUND

Very little research thus far has examined the decision making that underlies inappropriate social behavior (ISB) post-TBI (traumatic brain injury).

OBJECTIVES

To verify the usefulness of a new instrument, the Social Responding Task, for investigating whether, in social decision making, individuals with TBI, who present inappropriate social behavior (ISB), have difficulty anticipating their own feelings of embarrassment and others' angry reactions following an ISB.

METHODS

Seven subjects with TBI presenting with inappropriate social behavior (TBI-ISB), 10 presenting with appropriate social behavior (TBI-ASB), and 15 healthy controls were given 12 hypothetical scenarios three times, each time ending with a different behavioral response. Subjects were asked to gauge the likelihood of their displaying the behavior in that situation (part A) and of it being followed by an angry reaction from the other or by feelings of embarrassment in themselves (part B).

RESULTS

TBI-ISB subjects scored higher than TBI-ASB and healthy controls on a scale of likelihood of displaying an ISB. RESULTS regarding expectations of angry reactions from others and feelings of embarrassment after an ISB were similar among groups. Negative correlations between endorsement of an inappropriate behavior and anticipation of negative emotional consequences were significant for both TBI-ASB and control subjects, but not for TBI-ISB subjects.

CONCLUSIONS

RESULTS suggest that the TBI-ISB participants were likely to endorse an ISB despite being able to anticipate a negative emotional response in themselves or others, suggesting that there were other explanations for their poor behavior. A self-reported likely response to hypothetical social scenarios can be a useful approach for studying the neurocognitive processes behind the poor choices of individuals with TBI-ISB, but the task needs further validation studies. A comprehensive discussion follows on the underlying mechanisms affecting social behaviors after a TBI.

Impairments in social cognition following severe traumatic brain injury

Severe traumatic brain injury (TBI) leads to physical, neuropsychological, and emotional deficits that interfere with the individual’s capacity to return to his or her former lifestyle. This review focuses on social cognition, that is, the capacity to attend to, recognize and interpret interpersonal cues that guide social behavior. Social cognition entails ‘‘hot’’ processes, that is, emotion perception and emotional empathy and ‘‘cold’’ processes, that is, the ability to infer the beliefs, feelings, and intentions of others (theory of mind: ToM) to see their point of view (cognitive empathy) and what they mean when communicating (pragmatic inference). This review critically examines research attesting to deficits in each of these domains and also examines evidence for theorized mechanisms including specific neural networks, the role of simulation, and non-social cognition. Current research is hampered by small, heterogeneous samples and the inherent complexity of TBI pathology. Nevertheless, there is evidence that facets of social cognition are impaired in this population. New assessment tools to measure social cognition following TBI are required that predict everyday social functioning. In addition, research into remediation needs to be guided by the growing empirical base for understanding social cognition that may yet reveal how deficits dissociate following TBI.

Affective cognition and its disruption in mood disorders

In this review, we consider affective cognition, responses to emotional stimuli occurring in the context of cognitive evaluation. In particular, we discuss emotion categorization, biasing of memory and attention, as well as social/moral emotion. We discuss limited neuropsychological evidence suggesting that affective cognition depends critically on the amygdala, ventromedial frontal cortex, and the connections between them. We then consider neuroimaging studies of affective cognition in healthy volunteers, which have led to the development of more sophisticated neural models of these processes. Disturbances of affective cognition are a core and specific feature of mood disorders, and we discuss the evidence supporting this claim, both from behavioral and neuroimaging perspectives. Serotonin is considered to be a key neurotransmitter involved in depression, and there is a considerable body of research exploring whether serotonin may mediate disturbances of affective cognition. The final section presents an overview of this literature and considers implications for understanding the pathophysiology of mood disorder as well as developing and evaluating new treatment strategies.

Recognizing vocal expressions of emotion in patients with social skills deficits following traumatic brain injury

Perception of emotion in voice is impaired following traumatic brain injury (TBI). This study examined whether an inability to concurrently process semantic information (the "what") and emotional prosody (the "how") of spoken speech contributes to impaired recognition of emotional prosody and whether impairment is ameliorated when little or no semantic information is provided. Eighteen individuals with moderate-to-severe TBI showing social skills deficits during inpatient rehabilitation were compared with 18 demographically matched controls. Participants completed two discrimination tasks using spoken sentences that varied in the amount of semantic information: that is, (1) well-formed English, (2) a nonsense language, and (3) low-pass filtered speech producing "muffled" voices. Reducing semantic processing demands did not improve perception of emotional prosody. The TBI group were significantly less accurate than controls. Impairment was greater within the TBI group when accessing semantic memory to label the emotion of sentences, compared with simply making "same/different" judgments. Findings suggest an impairment of processing emotional prosody itself rather than semantic processing demands which leads to an over-reliance on the "what" rather than the "how" in conversational remarks. Emotional recognition accuracy was significantly related to the ability to inhibit prepotent responses, consistent with neuroanatomical research suggesting similar ventrofrontal systems subserve both functions.

Emotion perception deficits following traumatic brain injury: a review of the evidence and rationale for intervention

While the cognitive disturbances that frequently follow severe traumatic brain injury (TBI) are relatively well understood, the ways in which these affect the psychosocial functioning of people with TBI are yet to be determined and have thus received little attention in treatment research. Growing evidence indicates that a significant proportion of individuals with TBI demonstrate an inability to recognize affective information from the face, voice, bodily movement, and posture. Because accurate interpretation of emotion in others is critical for the successful negotiation of social interactions, effective treatments are necessary. Until recently, however, there have been no rehabilitation efforts in this area. The present review examines the literature on emotion perception deficits in TBI and presents a theoretical rationale for targeted intervention. Several lines of research relevant to the remediation of emotion perception in people with TBI are considered. These include work on emotion perception remediation with other cognitively impaired populations, current neuropsychological models of emotion perception and underlying neural systems, and recent conceptualizations of remediation processes. The article concludes with a discussion of the importance of carrying out efforts to improve emotion perception within a contextualized framework in which the day-to-day relevance of training is clear to all recipients.

Longitudinal aspects of emotion recognition in patients with traumatic brain injury

Changes in emotional and social behaviour are relatively common following traumatic brain injury (TBI). Impairments in recognising the emotional state of others may underlie some of the problems in social relationships that these patients experience. The few previous studies examining emotion recognition in TBI typically assessed patients once, long after the onset of brain injury, making it difficult to distinguish the direct effect of brain injury from the effects of environmental changes. This study examined 30 patients with TBI shortly after brain injury and 32 orthopaedic control patients on their recognition of emotions expressed in the face and the voice using discrimination and labelling tasks. These patients were followed up 1 year later to examine the longitudinal development of emotion recognition deficits. TBI patients were found to be impaired on emotion recognition compared to the control patients both early after injury and 1 year later. The fact that impairments in emotion recognition were evident early after TBI and no evidence of recovery over time was found, suggests a direct effect of brain injury.

Spousal relationship satisfaction following acquired brain injury: The role of insight and socio-emotional skill

Spousal relationships following brain injury are particularly vulnerable to strain and breakdown. Changes in personality and socio-emotional processing and behaviour have been implicated as causal factors. We examined spousal relationship satisfaction following an acquired brain injury to one partner. Couples affected by chronic pain and a group of healthy couples were used for comparison and control. Compared to healthy controls current satisfaction was poorer in the brain injury couples, and satisfaction with the relationship had reduced from pre to post-injury. We found an especially important role for empathy, which differentiated between the groups in terms of functioning and insight.

Psychiatric disturbances after traumatic brain injury: neurobehavioral and personality changes

Traumatic brain injuries (TBI) are frequently accompanied by psychiatric disturbances, which can include striking to relatively minor alterations in personality, behavior, and emotional regulation. The persistence of these neurobehavioral syndromes often leads to deleterious effects on recovery and rehabilitation outcomes. A recent surge of studies has emerged in the past several years to quantify the extent of psychiatric disorders in TBI and to describe differential clinical presentations. Various pre- and post-injury factors also have been hypothesized to contribute to the development and maintenance of psychiatric symptoms in survivors of brain injuries. The identification of high-risk individuals with distinct neuropathophysiological and psychosocial features permits the development of multidisciplinary and tailored approaches to the assessment, prevention, and management of the negative effects of personality and behavioral changes in TBI. This article summarizes the most recent research in these areas and highlights the gaps that need to be filled in subsequent future.

Functional neuroimaging correlates of functional amnesia

Especially in the field of memory encoding and retrieval, the results of functional neuroimaging have provided new insights in anatomico-functional interactions. In particular this holds true for the role of the prefrontal cortex in mnestic information processing, for the contribution and participation of the two hemispheres in various processes of information transmission, and for views on disturbed information processing after organically obvious and so-called psychogenic forms of memory impairments. This report particularly stresses the insights obtained by functional neuroimaging for probably environmentally triggered deficiencies in memory processing and discusses possible subtle neuroanatomical correlates of functional amnesias. It is especially emphasised that stress conditions and depressive states may modify the release of steroids (glucocorticoids) and transmitter agonists at the brain level with the consequence of selective memory disturbances which may manifest as a "mnestic block syndrome".

Assessing frontal lobe behavioral syndromes with the frontal lobe personality scale

Reliability and construct validity are reported for the Frontal Lobe Personality Scale (FLOPS), a brief neurobehavior rating scale. The FLOPS Family form was completed by family members of 24 frontal lobe brain-damaged patients, 15 non-frontal lobe brain- damaged patients, and 48 healthy controls. Intrascale reliability was demonstrated (internal consistency.96; split half.93). Validity studies of frontal lobe patients post-lesion compared to their pre-lesion status, to healthy controls, and of frontal lobe patients pre- and post-lesion compared to non-frontal lobe patients pre- and post-lesion, indicated that frontal lobe patients post-lesion showed significantly more frontal behavior than (a) pre-lesion frontal lobe patients, (b) healthy controls, and (c) post-lesion non-frontal lobe patients. The FLOPS appears to be useful for quantifying frontal lobe behavior in clinical and research settings.