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.
View Article and Find Full Text PDFIn 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.
View Article and Find Full Text PDFAlthough 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 (R) of the pathogen. The most notable example is rabies.
View Article and Find Full Text PDFSchizophrenia 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.
View Article and Find Full Text PDFHumans 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.
View Article and Find Full Text PDFFacial 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.
View Article and Find Full Text PDFContagious 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.
View Article and Find Full Text PDFFrontal 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.
View Article and Find Full Text PDFSecondary 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.
View Article and Find Full Text PDFDetermining 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.
View Article and Find Full Text PDFRestraint theory has been used to model the process that produces binge eating. However, there is no satisfactory explanation for the tendency of restrained eaters (REs) to engage in counterregulatory eating, an ostensible analogue of binge eating. Using functional magnetic resonance imaging (fMRI), the authors investigated brain activation of normal weight REs (N = 9) and unrestrained eaters (UREs; N = 10) when fasted and fed and viewing pictures of highly and moderately palatable foods and neutral objects.
View Article and Find Full Text PDFFront Evol Neurosci
July 2011
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.
View Article and Find Full Text PDFPeople 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.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFRecent 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).
View Article and Find Full Text PDFHumans 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.
View Article and Find Full Text PDFMaze 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.
View Article and Find Full Text PDFSmith et al. present a model that they suggest may clarify aspects of the phylogenetic distribution of metacognition, based on observation of what they call uncertainty monitoring. Although they suggest that their model is supported by data collected using monkeys and dolphins, their interpretation that nonhuman animal behaviors parallel thought processes in humans may be unwarranted.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
March 2008
Functional near-infrared spectroscopy (fNIR) measures changes in the relative levels of oxygenated and deoxygenated hemoglobin and has increasingly been used to assess neural functioning in the brain. In addition to the ongoing technological developments, investigators have also been conducting studies on functional mapping and refinement of data analytic strategies in order to better understand the relationship between the fNIR signal and brain activity. However, since fNIR is a relatively new functional brain imaging modality as compared to positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), it still lacks brain-mapping tools designed to allow researchers and clinicians to easily interact with their data.
View Article and Find Full Text PDFIt 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.
View Article and Find Full Text PDFAlthough theories that examine direct links between behavior and brain remain incomplete, it is known that brain expansion significantly correlates with caloric and oxygen demands. Therefore, one of the principles governing evolutionary cognitive neuroscience is that cognitive abilities that require significant brain function (and/or structural support) must be accompanied by significant fitness benefit to offset the increased metabolic demands. One such capacity is self-awareness (SA), which (1) is found only in the greater apes and (2) remains unclear in terms of both cortical underpinning and possible fitness benefit.
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