Self-Processing and Self-Face Reaction Time Latencies: A Review.

In this article, we detail the advantages of self-face identification latencies over more traditional tests of mirror self-recognition. Using reaction time latencies (measured in milliseconds) to identify different dimensions of the self, instead of relying on a simple dichotomous pass/fail mirror mark-test outcome, enables investigators to examine individual differences in self-processing time. This is a significant methodological step forward with important implications. The point of departure for our article is to detail research we and others have conducted on latencies for self-face identification, to show how self-processing occurs in the right side of the brain, how schizophrenia is a self-processing disorder, how self-face reaction time latencies implicate the existence of an underlying multiple modal self-processing system, and to explore ideas for future research.

SARS/CoV-2: Behavioral Host Manipulation.

INTRODUCTION: Though it has not been extensively studied, host manipulation has been documented for various pathogens. Examples of this phenomenon can be seen in cases of toxoplasmosis, rabies, and the influenza virus. An examination of the possible means by which SARS/CoV-2 alters the behavior of its host to spread among populations is elaborated. Indirect evidence that serves as indicators of this phenomenon is presented. METHODS: This is primarily a theoretical document. Many of the ideas raised are not amenable to direct testing due to ethical concerns. However, several indirect means by which to test the hypothesis are discussed. Primary data from cell phones regarding miles traveled, number of times leaving home, etc., are among the possible indirect measures. RESULTS: The rapid ability of the SARS/CoV-2 virus to spread through society suggests that it may cause behavioral changes of the host to increase its transmission. Numerous cases of super spreader events are noted that have provided meaningful measures of host manipulation. CONCLUSION: In the case of SARS/CoV-2, the largest advantage of the pathogen is likely that between 50% and 70% of those infected are asymptomatic (John's Hopkins Coronavirus Resource Center, John's Hopkins University Corona Virus Resource Center. Available at https://coronavirus.jhu.edu/map.html , 2020). This component is a threat to elderly individuals and those immunocompromised who are more likely to have severe complications from the virus and die. To spread within these groups, a seemingly healthy host is necessary to carry the virus to them. The goal of the virus is not to kill the host, but to survive and reproduce.

Hypothesized behavioral host manipulation by SARS-CoV2/COVID-19 infection.

Although not widely studied, behavioral host manipulation by various pathogens has been documented. Host manipulation is the process by which a pathogen evolves adaptations to manipulate the behavior of the host to maximize reproduction (Ro) of the pathogen. The most notable example is rabies. When a host is infected with the rabies virus it gets into the host's central nervous system and triggers hyper aggression. The virus is also present in the rabid animal's saliva so being bitten transmits the infection to a new host and the old host is left to eventually die if untreated. Toxoplasmosis is another example. When mice are infected they demonstrate a fearlessness toward cats, thus increasing their chances of being eaten. Toxoplasmosis needs the digestive tract of the feline to survive. Recent studies have shown that exposure to toxoplasmosis in humans (e.g., through cat feces) has also been associated with behavioral changes that are predicted to enhance the spread of the pathogen. Even the common influenza virus has been shown to selectively increase in-person sociality during the 48-hour incubation period, thus producing an obvious vector for transmission. Here we hypothesize that the novel coronavirus, SARS-CoV2, which produces the COVID-19 disease may produce similar host manipulations that maximize its transmission between humans.

Proposed symptom-based model of the origins of schizophrenia.

Schizophrenia is considered a severe mental illness and effects an estimated 1% of the world population. The evidence suggests that incidence rate has been and will continue to be stable over time. Here we adopt a symptomatology-focused evolutionary informed approach to discuss the possible biological adaptations of various presentations of schizophrenia. It is our contention that rather than thinking about schizophrenia as a single disorder, or even a spectrum of disorders, marked by social maladaptation and personal subjective distress, that an evolutionary interpretation based on adaptive nature of individual, or small clusters of, symptoms could prove to be more useful in better understanding the pathophysiology of schizophrenia and its relationship with other psychiatric diagnoses.

Working together may be better: activation of reward centers during a cooperative maze task.

Humans use theory of mind when predicting the thoughts and feelings and actions of others. There is accumulating evidence that cooperation with a computerized game correlates with a unique pattern of brain activation. To investigate the neural correlates of cooperation in real-time we conducted an fMRI hyperscanning study. We hypothesized that real-time cooperation to complete a maze task, using a blind-driving paradigm, would activate substrates implicated in theory of mind. We also hypothesized that cooperation would activate neural reward centers more than when participants completed the maze themselves. Of interest and in support of our hypothesis we found left caudate and putamen activation when participants worked together to complete the maze. This suggests that cooperation during task completion is inherently rewarding. This finding represents one of the first discoveries of a proximate neural mechanism for group based interactions in real-time, which indirectly supports the social brain hypothesis.

Curvaceous female bodies activate neural reward centers in men.

Facial symmetry, masculinity and shoulder-to-hip ratios in men convey information to mates about reproductive/genetic quality, the so-called "good genes" hypothesis. On the other hand waist-to-hip ratio conveys important reproductive information about women to men. Here using fMRI, men showed activation in neural reward centers when they viewed and rated the attractiveness of surgically optimally configured female bodies.

Yawn, yawn, yawn, yawn; yawn, yawn, yawn! The social, evolutionary and neuroscientific facets of contagious yawning.

Contagious yawning is a common phenomenon affecting upwards of 60% of healthy humans. It has also been observed, at a lesser rate, in great apes and other primates. Here I summarize the suggestion that contagious yawning is a primitive expression of social cognition, namely empathy. Susceptibility to contagious yawning is correlated with the speed in recognizing one's own face, theory of mind processing, and is also associated with activation in regions of the brain that have been associated with social cognitive processes. This suggests that contagious yawning may be an evolutionarily old process that begot a higher level of social cognition in certain species.

Optimal waist-to-hip ratios in women activate neural reward centers in men.

Secondary sexual characteristics convey information about reproductive potential. In the same way that facial symmetry and masculinity, and shoulder-to-hip ratio convey information about reproductive/genetic quality in males, waist-to-hip-ratio (WHR) is a phenotypic cue to fertility, fecundity, neurodevelopmental resources in offspring, and overall health, and is indicative of "good genes" in women. Here, using fMRI, we found that males show activation in brain reward centers in response to naked female bodies when surgically altered to express an optimal (approximately 0.7) WHR with redistributed body fat, but relatively unaffected body mass index (BMI). Relative to presurgical bodies, brain activation to postsurgical bodies was observed in bilateral orbital frontal cortex. While changes in BMI only revealed activation in visual brain substrates, changes in WHR revealed activation in the anterior cingulate cortex, an area associated with reward processing and decision-making. When regressing ratings of attractiveness on brain activation, we observed activation in forebrain substrates, notably the nucleus accumbens, a forebrain nucleus highly involved in reward processes. These findings suggest that an hourglass figure (i.e., an optimal WHR) activates brain centers that drive appetitive sociality/attention toward females that represent the highest-quality reproductive partners. This is the first description of a neural correlate implicating WHR as a putative honest biological signal of female reproductive viability and its effects on men's neurological processing.

Medial prefrontal cortex hyperactivation during social exclusion in borderline personality disorder.

Frontal systems dysfunction and abandonment fears represent central features of borderline personality disorder (BPD). BPD subjects (n=10) and matched non-psychiatric comparison subjects (n=10) completed a social-cognitive task with two confederates instructed to either include or exclude subjects from a circumscribed interaction. Evoked cerebral blood oxygenation in frontal cortex was measured using 16-channel functional near infrared spectroscopy. BPD subjects showed left medial prefrontal cortex hyperactivation during social exclusion suggesting potential dysfunction of frontolimbic circuitry.

Temporal order memory differences in Alzheimer's disease and vascular dementia.

Determining the order of events is essential for accurate memory recollection: an ability previously linked to both frontal and medial temporal functioning. Frontal-subcortical and medial temporal dysfunction typify vascular dementia (VaD) and Alzheimer's disease (AD), respectively. Therefore, we assessed patients' ordering abilities using a novel sequencing task that progressively increased memory load. VaD patients made more errors and selected more previously encountered stimuli than did AD. Curve analysis revealed a general decline in ordering for VaD whereas error production in AD is more dependent on memory load. These findings generally support the role of frontal-subcortical functioning in temporal order memory.

In-group and out-group membership mediates anterior cingulate activation to social exclusion.

FUNCTIONAL MAGNETIC RESONANCE IMAGING WAS EMPLOYED TO EXAMINE SENSITIVITY TO SOCIAL EXCLUSION IN THREE CONDITIONS: same-race, other-race, and self-resembling faces. The anterior cingulate cortex (ACC), specifically the dorsal ACC, has been targeted as a key substrate in the physical and social pain matrix and was hypothesized to regulate activation response to various facial conditions. We show that participants demonstrated greatest ACC activation when being excluded by self-resembling and same-race faces, relative to other-race faces. Additionally, participants expressed greater distress and showed increased ACC activation as a result of exclusion in the same-race condition relative to the other-race condition. A positive correlation between implicit racial bias and activation in the amygdala was also evident. Implicit attitude about other-race faces partly explains levels of concern about exclusion by out-group individuals. These findings suggest that individuals are more distressed and their brain (i.e. neural alarm system) responds with greater activation when being excluded by individuals whom they are more likely to share group membership with.

Self-face resemblance attenuates other-race face effect in the amygdala.

People respond favorably toward self-resembling faces. We investigated the pattern of responding in the amygdala of Caucasian participants to self-face resemblance expressed in same and other-race (African descent) faces. The amygdala response was 1) non-linear to faces as a function of self-facial resemblance and 2) attenuated to other-race self-resembling faces when regressed with implicit racial attitudes. These findings demonstrate that interactions of important facial social judgements are processed combinatorially in the amygdala.

Is family special to the brain? An event-related fMRI study of familiar, familial, and self-face recognition.

The face-processing network has evolved to respond differentially to different classes of faces depending on their relevance to the perceiver. For example, self-, familiar, and unknown faces are associated with activation in different neural substrates. Family should represent a special class of face stimuli that is of high relevance to individuals, because incorrect assignment of kinship can have dire consequences (e.g., incest, cuckoldry). Therefore evolution should have favored redundant mechanisms for detection of kin. We used fMRI to investigate the neural substrates associated with viewing faces of kin compared to other classes of faces (e.g., self-face, familiar face, and unknown face), and to examine the degree to which self-facial resemblance activated similar neural substrates. Contrasting kin faces with unknown faces activated substrates associated with self-face recognition, while comparing kin faces to friend faces activated posterior cingulate and cuneus. Similar posterior medial substrates were recruited when contrasting self-resembling faces with morphed faces of kin, suggesting these regions potentially represent computational processing about facial familiarity and identity. On the other hand, discrimination of self-resembling faces from familiar morphs activated anterior medial substrates (anterior cingulate cortex, ACC, medial prefrontal cortex, MPFC). These findings, and a region of interest (ROI) analysis, highlight the role of the extended face-processing network for discrimination of kin from familiar non-kin members of one's social group based on self-referent phenotypic cues.

Implicit trustworthiness ratings of self-resembling faces activate brain centers involved in reward.

On the basis of Hamilton's (Hamilton, W. D. (1964). The genetical evolution of social behavior I, II. Journal of Theoretical Biology, 7, 17-52) theory of inclusive fitness, self-facial resemblance is hypothesized as a mechanism for self-referent phenotypic matching by which humans can detect kin. To understand the mechanisms underlying pro-sociality toward self-resembling faces, we investigated the neural correlates of implicit trustworthiness ratings for self-resembling faces. Here we show that idiosyncratic trustworthiness ratings of self-resembling faces predict brain activation in the ventral inferior, middle and medial frontal gyri, substrates involved in reward processing. These findings demonstrate that neural reward centers are implicated in evaluating implicit pro-social behaviors toward self-resembling faces. These findings suggest that humans have evolved to use neurocomputational architecture dedicated to face processing and reward evaluation for the differentiation of kin, which drives implicit idiosyncratic affectively regulated social interactions.

Neural correlates of self-face recognition: an effect-location meta-analysis.

Recent evidence from neuropsychological patients with focalized lesions and functional brain imaging studies indicate that processing of self is distinguishable from processing of information about others (e.g., recognizing a familiar face). Here, we conduct an effect-location meta-analysis (Fox et al., 1998) of 9 functional neuroimaging studies of self-face recognition. The evidence provides support for a right-dominated, but largely bilaterally distributed model for self-face processing. Four areas are consistently activated: the left fusiform gyrus, bilateral middle and inferior frontal gyri, and right precuneus. The evidence is interpreted in light of a developing model of self-face recognition as part of a larger social cognitive stream of processing.

The neural basis of facial resemblance.

Humans respond favourably to self-resembling faces. Self-facial resemblance is a mechanism for self-referent phenotypic matching by which humans can differentiate genetic kin from other members of a social group. To better understand how the brain makes discriminations between kin and non-kin, we investigated the neural correlates of self-resemblance in faces that were transformed along the dimensions of race and sex. We show that anterior cingulate and medial prefrontal cortex were associated with discrimination between closely resembling racially similar same-sex faces, whereas lower-level visual regions were involved in discriminating self-reference when faces are more characteristically distinct. These findings extend previous literature, which has shown posterior medial cortical involvement in self-reference, by demonstrating a clear anterior-posterior differentiation based on closeness of self-referent match. Our findings suggest the evolution of anterior-posterior neural organization associated with making self-other judgements pertinent to kin recognition.

Maze Suite 1.0: a complete set of tools to prepare, present, and analyze navigational and spatial cognitive neuroscience experiments.

Maze Suite is a complete set of tools that enables researchers to perform spatial and navigational behavioral experiments within interactive, easy-to-create, and extendable (e.g., multiple rooms) 3-D virtual environments. Maze Suite can be used to design and edit adapted 3-D environments, as well as to track subjects' behavioral performance. Maze Suite consists of three main applications: an editing program for constructing maze environments (MazeMaker), a visualization/rendering module (MazeWalker), and an analysis and mapping tool (MazeViewer). Each of these tools is run and used from a graphical user interface, thus making editing, execution, and analysis user friendly. MazeMaker is a .NET architecture application that can easily be used to create new 3-D environments and to edit objects (e.g., geometric shapes, pictures, landscapes, etc.) or add them to the environment effortlessly. In addition, Maze Suite has the capability of sending signal-out pulses to physiological recording devices, using standard computer ports. Maze Suite, with all three applications, is a unique and complete toolset for researchers who want to easily and rapidly deploy interactive 3-D environments.

Distinguishing between neuropsychological malingering and exaggerated psychiatric symptoms in a neuropsychological setting.

It is unclear whether symptom validity test (SVT) failure in neuropsychological and psychiatric domains overlaps. Records of 105 patients referred for neuropsychological evaluation, who completed the Test of Memory Malingering (TOMM), Reliable Digit Span (RDS), and Millon Clinical Multiaxial Inventory-III (MCMI-III), were examined. TOMM and RDS scores were uncorrelated with MCMI-III symptom validity indices and factor analysis revealed two distinct factors for neuropsychological and psychiatric SVTs. Only 3.5% of the sample failed SVTs in both domains, 22.6% solely failed the neuropsychological SVT, and 6.1% solely failed the psychiatric SVT. The results support a dissociation between neuropsychological malingering and exaggeration of psychiatric symptoms in a neuropsychological setting.