Because little is known about the human trait of affiliation, we provide a novel neurobehavioral model of affiliative bonding. Discussion is organized around processes of reward and memory formation that occur during approach and consummatory phases of affiliation. Appetitive and consummatory reward processes are mediated independently by the activity of the ventral tegmental area (VTA) dopamine (DA)–nucleus accumbens shell (NAS) pathway and the central corticolimbic projections of the u-opiate system of the medial basal arcuate nucleus, respectively, although these two projection (...) systems functionally interact across time. We next explicate the manner in which DA and glutamate interact in both the VTA and NAS to form incentive-encoded contextual memory ensembles that are predictive of reward derived from affiliative objects. Affiliative stimuli, in particular, are incorporated within contextual ensembles predictive of affiliative reward via: (a) the binding of affiliative stimuli in the rostral circuit of the medial extended amygdala and subsequent transmission to the NAS shell; (b) affiliative stimulus-induced opiate potentiation of DA processes in the VTA and NAS; and (c) permissive or facilitatory effects of gonadal steroids, oxytocin (in interaction with DA), and vasopressin on (i) sensory, perceptual, and attentional processing of affiliative stimuli and (ii) formation of social memories. Among these various processes, we propose that the capacity to experience affiliative reward via opiate functioning has a disproportionate weight in determining individual differences in affiliation. We delineate sources of these individual differences, and provide the first human data that support an association between opiate functioning and variation in trait affiliation. Key Words: affiliation corticolimbic-striatal networks; appetitive and consummatory reward; dopamine; oxytocin; personality; social bonds; social memory; u-opiates. (shrink)

Expectation-based theories of language comprehension, in particular Surprisal Theory, go a long way in accounting for the behavioral correlates of word-by-word processing difficulty, such as reading times. An open question, however, is in which component of the Event-Related brain Potential signal Surprisal is reflected, and how these electrophysiological correlates relate to behavioral processing indices. Here, we address this question by instantiating an explicit neurocomputational model of incremental, word-by-word language comprehension that produces estimates of the N400 and the P600—the two most (...) salient ERP components for language processing—as well as estimates of “comprehension-centric” Surprisal for each word in a sentence. We derive model predictions for a recent experimental design that directly investigates “world-knowledge”-induced Surprisal. By relating these predictions to both empirical electrophysiological and behavioral results, we establish a close link between Surprisal, as indexed by reading times, and the P600 component of the ERP signal. The resultant model thus offers an integrated neurobehavioral account of processing difficulty in language comprehension. (shrink)

Trust and reciprocity are cornerstones of human nature, both at the levels of close interpersonal relationships and economic/societal structures. Being able to both place trust in others and decide whether to reciprocate trust placed in us is rooted in implicit and explicit processes that guide expectations of others, help reduce social uncertainty and build relationships. This review will highlight neurobehavioral mechanisms supporting trust and reciprocity, through the lens of implicit and explicit social appraisal and learning processes. Significant consideration will be (...) given to the neural underpinnings of these implicit and explicit processes, and special focus will center on the underlying neurocomputational mechanisms facilitating the integration of implicit and explicit signals supporting trust and reciprocity. Finally, this review will conclude with discussion of how we can leverage findings regarding the neurobehavioral mechanisms supporting trust and reciprocity to better inform our understanding of mental health disorders characterized by social dysfunction. (shrink)

psychiatric diagnoses such as attention deficit hyperactivity disorder is a rapidly growing and globally increasing phenomenon, not least in different educational contexts such as in family and in school. Children and youths labelled as ADHD are challenging normative claims in terms of nurturing and education, whereas those labelled as ADHD are considered a risk for society to handle. The dominant paradigm regarding ADHD is biomedical, where different levels of attention and activity-impulsivity are perceived as neurobiological dys/functions within the brain best (...) managed by means of an individual diagnosis and instrumental pedagogy. The majority of those labelled as having ADHD encounter a dominant educational model in the form of what is referred to in this article as neurobehaviorism, which is based on onto-epistemological violence. As opposed to this act of violence against being—and against the psychiatrized subject—a less violent educational model is proposed, based on French philosopher Alain Badiou’s ontological examination of being and his concept of love as a truth procedure. In terms of the latter, the focus is on the potential of the encounter as a ‘Two scene of love’. Here, the encounter is a place where it is possible to create new truths and subjects, instead of taking the individual diagnosis as an axiom which only leads to individuals having fixed identities codified in a hierarchical order. This argument is drawn from the ‘mathematical’ formula 1 + 1 = ♥, which originates from an online forum for people who have come into contact with ADHD in one way or another. (shrink)

This paper builds upon a critically clarified statement of the triune brain concept to set out the conflict systems neurobehavioral model. The model defines the reciprocal algorithms of behavior from evolved brain structure. The algorithms are driven by subjectively experienced behavioral tension as the self‐preservational programming, common to our ancestral vertebrates, frequently tugs and pulls against the affectional program‐ming of our mammalian legacy. The yoking of the dual algorithmic dynamic accounts for the emergence of moral and spiritual consciousness as manifested (...) in the universal norm of reciprocity and in the work of such thinkersas Martin Buber and Paul Tillich. (shrink)

We identify the significance and typical requirements of developmental analyses of the microbiome-gut-brain in parents, offspring, and parent-offspring relations, which have particular importance for neurobehavioral outcomes in mammalian species, including humans. We call for a focus on behavioral measures of social-emotional function. Methodological approaches to interpreting relations between the microbiota and behavior are discussed.

Braitenberg et al.'s view that the cerebellum contributes to multijoint sequences of movement is too narrow to account adequately for results from new anatomical, neurobehavioral, and neuroimaging studies. A broader view is that the cerebellum modulates attention, sensory, motor, and other neural systems in order to accomplish its prime function, which is to learn to predict and prepare for imminent information acquisition, analysis, or action.

Neuroconstructivism, Vol. 1: How the Brain Constructs Cognition implies that brain functioning depends on biofeedback and ecological trajectories. Using the building blocks of Boolean algebra known as logic gates and models of distributed control systems, I suggest that levels of regulatory states are responsible for optimal, pathological, and developmental processes. I include the impact of regulatory and nonregulatory functions on structural development.

Patients with strokes to the Anterior Communicating Artery pose an important challenge to rehabilitation teams due to a particular mix of cognitive and behavioral impairments. These deficits often compromise engagement with rehabilitation, learning and generalization. The goal of this article is to describe the long-term presentation of a patient with an ACoA stroke as well as her rehabilitation needs and the many challenges experienced by the rehabilitation team when attempting to facilitate functional, vocational and psychosocial recovery. Based on this case, (...) and the existing literature, a neuropsychological rehabilitation framework to understand and address the specific problems and needs of this population is proposed. This framework demands rehabilitation teams to consider: the slow pattern of recovery of this population, the interaction between cognitive and behavioral impairments, the relevance of physical and social environments, the value of personal projects and the need to include psychological and relational interventions. (shrink)

Dance has traditionally been viewed from a Eurocentric perspective as a mode of self-expression that involves the human body moving through space, performed for the purposes of art, and viewed by an audience. In this Hypothesis and Theory article, we synthesize findings from anthropology, sociology, psychology, dance pedagogy, and neuroscience to propose The Synchronicity Hypothesis of Dance, which states that humans dance to enhance both intra- and inter-brain synchrony. We outline a neurocentric definition of dance, which suggests that dance involves (...) neurobehavioral processes in seven distinct areas including sensory, motor, cognitive, social, emotional, rhythmic, and creative. We explore The Synchronicity Hypothesis of Dance through several avenues. First, we examine evolutionary theories of dance, which suggest that dance drives interpersonal coordination. Second, we examine fundamental movement patterns, which emerge throughout development and are omnipresent across cultures of the world. Third, we examine how each of the seven neurobehaviors increases intra- and inter-brain synchrony. Fourth, we examine the neuroimaging literature on dance to identify the brain regions most involved in and affected by dance. The findings presented here support our hypothesis that we engage in dance for the purpose of intrinsic reward, which as a result of dance-induced increases in neural synchrony, leads to enhanced interpersonal coordination. This hypothesis suggests that dance may be helpful to repattern oscillatory activity, leading to clinical improvements in autism spectrum disorder and other disorders with oscillatory activity impairments. Finally, we offer suggestions for future directions and discuss the idea that our consciousness can be redefined not just as an individual process but as a shared experience that we can positively influence by dancing together. (shrink)

Paul MacLean, founder and long-time chief ofthe Laboratory of Brain Evolution and Behavior,National Institutes of Health, is a pioneeringfigure in the emergent field of evolutionaryneuroscience. His influence has been widelyfelt in the development of biologicalpsychiatry and has led to a considerableliterature on evolutionary approaches toclinical issues. MacLean's work is alsoenjoying a resurgence of interest in academicareas of neuroscience and evolutionarypsychology which have previously shown littleinterest or knowledge of his extensive work. This chapter builds on MacLean's work to bringtogether new insights (...) into the neuralarchitecture of human development, hierarchy,conflict behavior, and reciprocity in the formof the Conflict Systems Neurobehavioral Model. Hamilton 's rule of kinship altruism orinclusive fitness is proposed to be the gene'seye complement to MacLean's evolutionaryneuroscience and the CSN Model derivedtherefrom. Hierarchy, conflict behavior andreciprocity are also central issues in healthydevelopment as well as in clinical syndromes ofdepression, mania, and other socialmaladjustments. The emerging insights permitthe integration of the concept of inclusivefitness underpinning evolutionary psychologywith MacLean's perspective on evolutionaryneuroscience as well as the definition of newchallenges for mental health and socialstability. The policy implications areindicated. (shrink)

Aphantasia is a recently discovered disorder characterised by the total incapacity to generate visual forms of mental imagery. This paper proposes that aphantasia raises important theoretical concerns for the ongoing debate in the philosophy and science of consciousness over the nature of dreams. Recent studies of aphantasia and its neurobehavioral correlates reveal that the majority of aphantasics, whilst unable to produce visual imagery while awake, nevertheless retain the capacity to experience rich visual dreams. This finding constitutes a novel explanandum for (...) theories of dreaming. Specifically, I argue that the recent dream reports of aphantasics constitute an empirical challenge to the emerging family of views which claim that dreams are essentially imaginative experiences, constitutively involving the kinds of mental imagery which aphantasics, ex-hypothesi, lack. After presenting this challenge in the context of Jonathan Ichikawa’s recent arguments for this view, I argue that this empirical challenge may be overcome if the imagination theorist abandons Ichikawa’s account of dreaming in favour of a modified version. This involves the claim that dreams are essentially inactive and constitutively involve non voluntary forms of imagination. I conclude with a suggestion for further research which can test the viability of this alternative hypothesis, and move the debate forward. (shrink)

A long history of research has revealed many neurophysiological changes and concomitant behavioral impacts of sleep deprivation, sleep restriction, and circadian rhythms. Little research, however, has been conducted in the area of computational cognitive modeling to understand the information processing mechanisms through which neurobehavioral factors operate to produce degradations in human performance. Our approach to understanding this relationship is to link predictions of overall cognitive functioning, or alertness, from existing biomathematical models to information processing parameters in a cognitive architecture, leveraging (...) the strengths from each to develop a more comprehensive explanation. The integration of these methodologies is used to account for changes in human performance on a sustained attention task across 88 h of total sleep deprivation. The integrated model captures changes due to time awake and circadian rhythms, and it also provides an account for underlying changes in the cognitive processes that give rise to those effects. The results show the potential for developing mechanistic accounts of how fatigue impacts cognition, and they illustrate the increased explanatory power that is possible by combining theoretical insights from multiple methodologies. (shrink)

The appearance of consciousness in the universe remains one of the major mysteries unsolved by science or philosophy. Absent an agreed-upon definition of consciousness or even a convenient system to test theories of consciousness, a confusing heterogeneity of theories proliferate. In pursuit of clarifying this complicated discourse, we here interpret various frameworks for the scientific and philosophical study of consciousness through the lens of social insect evolutionary biology. To do so, we first discuss the notion of a forward test versus (...) a reverse test, analogous to the normal and revolutionary phases of the scientific process. Contemporary theories of consciousness are forward tests for consciousness, in that they strive to become a means to classify the level of consciousness of arbitrary states and systems. Yet no such theory of consciousness has earned sufficient confidence such that it might be actually used as a forward test in ambiguous settings. What is needed now is thus a legitimate reverse test for theories of consciousness, to provide internal and external calibration of different frameworks. A reverse test for consciousness would ideally look like a method for referencing theories of consciousness to a tractable model system. We introduce the Ant Colony Test as a rigorous reverse test for consciousness. We show that social insect colonies, though disaggregated collectives, fulfill many of the prerequisites for conscious awareness met by humans and honey bee workers. A long lineage of philosophically-neutral neurobehavioral, evolutionary, and ecological studies on social insect colonies can thus be redeployed for the study of consciousness in general. We suggest that the ACT can provide insight into the nature of consciousness, and highlight the ant colony as a model system for ethically performing clarifying experiments about consciousness. (shrink)

Male sexual arousal (SA) has been known as a multidimensional experience involving closely interrelated and coordinated neurobehavioral components that rely on widespread brain regions. Recent functional neuroimaging studies have shown relation between abnormal/altered dynamics in these circuits and male sexual dysfunction. However, alterations in the topological1 organization of structural brain networks in male sexual dysfunction are still unclear. Here, we used graph theory2 to investigate the topological properties of large-scale structural brain networks, which were constructed using inter-regional correlations of cortical (...) thickness between 78 cortical regions (subcortical regions were not included due to the used cortical surface model) in 40 patients with psychogenic erectile dysfunction (pED) and 39 normal controls. Compared with normal controls, pED patients exhibited a less optimal global topological organization with reduced global and increased local efficiencies. Our results suggest disrupted neural integration among distant brain regions in pED patients, consistent with previous reports of impaired white matter structure and abnormal functional integrity in pED. Additionally, disrupted global network topology in pED was observed to be primarily relevant to altered subnetwork and nodal properties within the networks mediating the cognitive, motivational and inhibitory processes of male SA, possibly indicating disrupted integration of these networks in the whole brain networks and might account for pED patients’ abnormal cognitive, motivational and inhibitory processes for male SA. In total, our findings provide evidence for disrupted integrity in large-scale brain networks underlying the neurobehavioral processes of male SA in pED and provide new insights into the understanding of the pathophysiological mechanisms of pED. (shrink)

The appearance of consciousness in the universe remains one of the major mysteries unsolved by science or philosophy. Absent an agreed-upon definition of consciousness or even a convenient system to test theories of consciousness, a confusing heterogeneity of theories proliferate. In pursuit of clarifying this complicated discourse, we here interpret various frameworks for the scientific and philosophical study of consciousness through the lens of social insect evolutionary biology. To do so, we first discuss the notion of a forward test versus (...) a reverse test, analogous to the normal and revolutionary phases of the scientific process. Contemporary theories of consciousness are forward tests for consciousness, in that they strive to become a means to classify the level of consciousness of arbitrary states and systems. Yet no such theory of consciousness has earned sufficient confidence such that it might be actually used as a forward test in ambiguous settings. What is needed now is thus a legitimate reverse test for theories of consciousness, to provide internal and external calibration of different frameworks. A reverse test for consciousness would ideally look like a method for referencing theories of consciousness to a tractable (and non-human) model system. We introduce the Ant Colony Test (ACT) as a rigorous reverse test for consciousness. We show that social insect colonies, though disaggregated collectives, fulfill many of the prerequisites for conscious awareness met by humans and honey bee workers. A long lineage of philosophically-neutral neurobehavioral, evolutionary, and ecological studies on social insect colonies can thus be redeployed for the study of consciousness in general. We suggest that the ACT can provide insight into the nature of consciousness, and highlight the ant colony as a model system for ethically performing clarifying experiments about consciousness. (shrink)

Painful pains are, paradigmatically, unpleasant and motivating. The dominant view amongst philosophers and pain scientists is that these two features are essentially related and sufficient for painfulness. In this article, I first offer scientifically informed characterizations of both unpleasantness and motivational oomph and argue against other extant accounts. I then draw on folk-characterized cases and current neurobiological and neurobehavioral evidence to argue that both dominant positions are mistaken. Unpleasantness and motivational oomph doubly dissociate and, even taken together, are insufficient for (...) painfulness. (shrink)

Dynamic intra-individual variability (IIV) in cardiac vagal control across multiple situations is believed to contribute to adaptive cognition under stress; however, a dearth of research has empirically tested this notion. To this end, we examined 25 U.S. Army Soldiers (all male, Mean Age= 30.73, SD = 7.71) whose high-frequency heart rate variability (HF-HRV) was measured during a resting baseline and during three conditions of a shooting task (training, low stress, high stress). Response inhibition was measured as the correct rejection of (...) friendly targets during the low and high stress conditions. We tested the association between the standard deviation of HF-HRV across all four task conditions (IIV in vagal control) and changes in response inhibition between low and high stress. Greater differences in vagal control between conditions (larger IIV) were associated with higher tonic vagal control during rest, and stronger stress-related decreases in response inhibition. These results suggest that flexibility in vagal control is supported by tonic vagal control, but this flexibility also uniquely relates to adaptive cognition under stress. Findings are consistent with neurobehavioral and dynamical systems theories of vagal function. (shrink)

Caretaking stability in the early life environment supports neurobehavioral development, while instability and neglect constitute adverse environments that can alter maturational processes. Research in humans suggests that different types of early life adversity can have differential effects on caretaker relationships and later cognitive and social development; however, identifying mechanistic underpinnings will require animal models with translational validity. Two common rodent models, maternal separation and limited bedding, influence the mother-infant relationship during a critical window of development. We hypothesized that these paradigms (...) may affect the development of communication strategies on the part of the pup. Ultrasonic vocalizations are a care-eliciting mechanism and ethologically relevant response to stressors in the rat pup. USV emission rates and acoustic parameters change throughout early development, presenting the opportunity to define developmental milestones in USVs that would reflect neurobehavioral aberrations if disrupted. This study investigated the effects of MS or LB on the dam-pup relationship by quantifying pup USVs, maternal behavior, and the relationship between the two. First, we used a generalized additive model approach to establish typical developmental trajectories of USV acoustic properties and determine windows of change in MS or LB rearing. Additionally, we quantified maternal behaviors and the predictability of maternal care sequences using an entropy rate calculation. MS and LB each shifted the developmental trajectories of USV acoustic parameters and call types in a sex-specific manner. MS more often impacted male USVs, while LB impacted female USVs. MS dams spent more time passive nursing, and LB dams spent more time on the nest. The predictability of maternal care was associated with the rate of USV emissions exclusively in females. Taken together, findings demonstrate sex- and model-specific effects of rearing environments on a novel developmental trajectory involving the mother-infant relationship, facilitating the translation of animal ELA paradigms to assess later-life consequences. (shrink)

Müller & Schumann (M&S) deserve applause for their interdisciplinary examination of drug use, evolution, and learning. Further steps can deepen their evolutionary analysis: a focus on adaptive benefits, a distinction between approach and consummatory behaviors, an examination of how drugs can create adaptive lag through changing human niche construction, the importance of other neurobehavioral mechanisms in drug use besides instrumentalization, and the importance of sociocultural dynamics and neural plasticity in both human evolution and drug use.

Brain damage can cause massive changes in consciousness levels. From a clinical and ethical point of view it is desirable to assess the level of residual consciousness in unresponsive patients. However, no direct measure of consciousness exists, so we run into the philosophical problem of other minds. Neurologists often make implicit use of a Turing test-like procedure in an attempt to gain access to damaged minds, by monitoring and interpreting neurobehavioral responses. New brain imaging techniques are now being developed that (...) permit communication with unresponsive patients, using their brain signals as carriers of messages relating to their mental states. (shrink)

Background: The broad autism phenotype includes subclinical autistic characteristics found to have a higher prevalence in unaffected family members of individuals with autism. These characteristics primarily affect the social aspects of language, communication, and human interaction. The current research focuses on possible neurobehavioral characteristics associated with the broad autism phenotype. Methods: We used a face-processing task associated with atypical patterns of gaze fixation and brain function in autism while collecting brain functional magnetic resonance imaging (fMRI) and eye tracking in unaffected (...) siblings of individuals with autism. Results: We found robust differences in gaze fixation and brain function in response to images of human faces in unaffected siblings compared with typically developing control individuals. The siblings’ gaze fixations and brain activation patterns during the face processing task were similar to that of the autism group and showed decreased gaze fixation along with diminished fusiform activation compared with the control group. Furthermore, amygdala volume in the siblings was similar to the autism group and was significantly reduced compared with the control group. Conclusions: Together, these findings provide compelling evidence for differences in social/emotional processing and underlying neural circuitry in siblings of individuals with autism, supporting the notion of unique endophenotypes associated with the broad autism phenotype. (shrink)

Commentary on our target article centers around six main topics: (1) strategies in modeling the neurobehavioral foundation of human behavioral traits; (2) clarification of the construct of affiliation; (3) developmental aspects of affiliative bonding; (4) modeling disorders of affiliative reward; (5) serotonin and affiliative behavior; and (6) neural considerations. After an initial important research update in section R1, our Response is organized around these topics in the following six sections, R2 to R7.

In contrast to the biallelic expression of most genes, expression of genes subject to genomic imprinting is monoallelic and based on the sex of the transmitting parent. Possession of only a single active allele can lead to deleterious health consequences in humans. Aberrant expression of imprinted genes, through either genetic or epigenetic alterations, can result in developmental failures, neurodevelopmental and neurobehavioral disorders and cancer. The evolutionary emergence of imprinting occurred in a common ancestor to viviparous mammals after divergence from the (...) egg‐laying monotremes. Current evidence indicates that imprinting regulation in metatherian mammals differs from that in eutherian mammals. This suggests that imprinting mechanisms are evolving from those that were established 150 million years ago. Therefore, comparing genomic sequence of imprinted domains from marsupials and eutherians with those of orthologous regions in monotremes offers a potentially powerful bioinformatics approach for identifying novel imprinted genes and their regulatory elements. Such comparative studies will also further our understanding of the molecular evolution and phylogenetic distribution of imprinted genes. BioEssays 25:577–588, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

Schizophrenia (SCZ) is a severe neurodevelopmental disorder affecting 1% of populations worldwide with a grave disability and socioeconomic burden. Current antipsychotic medications are effective treatments for positive symptoms, but poorly address negative symptoms and cognitive symptoms, warranting the development of better treatment options. Further understanding of SCZ pathogenesis is critical in these endeavors. Accumulating evidence has pointed to the role of mitochondria and metabolic dysregulation in SCZ pathogenesis. This review critically summarizes recent studies associating a compromised mitochondrial function with people (...) with SCZ, including postmortem studies, imaging studies, genetic studies, and induced pluripotent stem cell studies. This review also discusses animal models with mitochondrial dysfunction resulting in SCZ‐relevant neurobehavioral abnormalities, as well as restoration of mitochondrial function as potential therapeutic targets. Further understanding of mitochondrial dysfunction in SCZ may open the door to develop novel therapeutic strategies that can address the symptoms that cannot be adequately addressed by current antipsychotics alone. (shrink)

The cognitive and behavioral functions of the frontal lobes have been of great interest to neuroscientists, neurologists, psychologists and psychiatrists. Recent technical advances have made it possible to trace their neuroanatomical connections more precisely and to conduct evoked potential and neuroimaging studies in patients. This book presents a broad and authoritative synthesis of research progress in this field. It encompasses neuroanatomical studies; experiments involving temporal organization and working memory tasks in non-human primates; clinical studies of patients following frontal lobe excisions (...) for intractable epilepsy; metabolic imaging in schizophrenia and affective disorder; neurobehavioral studies of patients with dementia, frontal lobe tumors, and head injuries; magnetic resonance imaging methods for studying human frontal lobe anatomy; theoretical approaches to describing frontal lobe functions; and rehabilitation of patients with frontal lobe damage including their core problem of diminished awareness. Written by a distinguished group of neuroscientists, psychologists and clinicians, Frontal Lobe Function and Dysfunction provides the best current source of information on this region of the brain and its role in cognition, behavior and clinical disorders. (shrink)

This book investigates the relationship between our present and future selves. It focuses specifically on diachronic self-regarding decisions: choices involving our earlier and later selves, in which the earlier self makes a decision for the later self. The author connects the scientific understanding of the neurobehavioral processes at the core of individuals' perceptions of their future selves with the philosophical reflection on individuals' moral relationship with their future selves. She delineates a descriptive theory of the perception of the future self (...) that is based on empirical evidence and that systematizes and integrates the current theoretical literature. She then argues for the morality of prudence and interprets diachronic self-regarding decisions as decisions between two agents-the earlier and later selves-that belong to the realm of intergenerational ethics, which regulates the relationship between contemporary people and future generations. Finally, the author provides a moral theory of prudence based on respect for one's agency. This theory identifies what the present and the future selves owe to one another in diachronic self-regarding decisions. Moral Choices for Our Future Selves will be of interest to researchers and students working in ethics, moral psychology, philosophy of mind, and cognitive science. (shrink)

A high percent of oxidative energy metabolism is needed to support brain growth during infancy. Unhealthy diets and limited nutrition, as well as other environmental insults, can compromise these essential developmental processes. In particular, iron deficiency anemia has been found to undermine both normal brain growth and neurobehavioral development. Even moderate ID may affect neural maturation because when iron is limited, it is prioritized first to red blood cells over the brain. A primate model was used to investigate the neural (...) effects of a transient ID and if deficits would persist after iron treatment. The large size and postnatal growth of the monkey brain makes the findings relevant to the metabolic and iron needs of human infants, and initiating treatment upon diagnosis of anemia reflects clinical practice. Specifically, this analysis determined whether brain maturation would still be compromised at 1 year of age if an anemic infant was treated promptly once diagnosed. The hematology and iron status of 41 infant rhesus monkeys was screened at 2-month intervals. Fifteen became ID; 12 met clinical criteria for anemia and were administered iron dextran and B vitamins for 1–2 months. MRI scans were acquired at 1 year. The volumetric and diffusion tensor imaging measures from the ID infants were compared with monkeys who remained continuously iron sufficient. A prior history of ID was associated with smaller total brain volumes, driven primarily by significantly less total gray matter and smaller GM volumes in several cortical regions. At the macrostructual level, the effect on white matter volumes was not as overt. However, DTI analyses of WM microstructure indicated two later-maturating anterior tracts were negatively affected. The findings reaffirm the importance of iron for normal brain development. Given that brain differences were still evident even after iron treatment and following recovery of iron-dependent hematological indices, the results highlight the importance of early detection and preemptive supplementation to limit the neural consequences of ID. (shrink)

The rapidly expanding universe of information, media, and learning experiences available through digital technology is creating unique opportunities and vulnerabilities for children and adolescents. These issues are particularly salient during the developmental window at the transition from childhood into adolescence. This period of early adolescence is a time of formative social and emotional learning experiences that can shape identity development in both healthy and unhealthy ways. Increasingly, many of these foundational learning experiences are occurring in on-line digital environments. These expanding (...) vulnerabilities and opportunities are being further amplified for young adolescents growing up in low resourced settings around the world. Cultural and contextual factors influence access, use, and appropriation of digital technology. Further, neurobehavioral changes associated with the onset of puberty often coincide with entry into social media and more autonomous use of technology. In low-and-middle-income countries (LMICs), disparities in access, use, and appropriation of digital media can amplify prevailing economic gaps, and compound gender inequalities during early adolescence. In LMICs, adolescents are often the early adopters of mobile technology and social media platforms. While the impact of social media on the well-being, particularly mental health, of young adolescents has been a focus of research in high-income countries (HICs), much less is known about the impacts of social media use on young adolescents in LMICs. In this paper, we review what is known about the interaction between digital media and early adolescent development. We highlight crucial gaps in the evidence in LMICs; and describe some hypotheses and areas for future research to address these compelling issues. (shrink)

Charles Darwin is generally credited with having formulated the first systematic attempt to explain the evolutionary origins and function of the expression of emotions in animals and humans. His ingenious theory, however, was burdened with popular misconceptions about human phylogenetic heritage and bore the philosophical and theoretical deficiencies of the brain science of his era that his successors strove to overcome. In their attempts to rectify Darwin?s errors, William James, James Mark Baldwin and John Dewey each made important contributions to (...) a theory of emotion, which attempted to put it on a more secure philosophical and scientific footing. My contention is that Dewey and his collaborator, infant experimentalist Myrtle McGraw, succeeded where their contemporaries failed. They pointed the way out of the morass of recapitulationism, and showed how a developmental theory of consciousness, mind and emotion could be formulated that avoided the epistemological and ontological pitfalls of Darwin?s theory. Drawing on an extensive body of research from contemporary experimental studies of infant development, this essay attempts to put the questions raised by these historical figures about the structure, function and value of emotions in a theoretical framework. A developmental theory is proposed about the complex, interacting neurobiological and neurobehavioral factors that contribute to human emotional development. This theory identifies the possible relationships among emotions, consciousness and mind and how their co-development influences the capacity of young children to form moral judgments. (shrink)

The last decade has seen a dramatic increase in studies on the development, function and evolution of asymmetries in vertebrates, including amphibians. Here we discuss current knowledge of behavioral and anatomical asymmetries in amphibians. Behavioral laterality in the response of both adult and larval anurans to presumed predators and competitors is strong and may be related, respectively, to laterality in the telencephalon of adults and the Mauthner neurons of tadpoles. These behavior lateralities, however, do not seem to correlate with visceral (...) asymmetries in the same animals. We briefly compare what is known about the evolution and development of asymmetry in the structure and function of amphibians with what is known about asymmetries in other chordate and non‐chordate groups. Available data suggest that the majority of asymmetries in amphibians fall into two independent groups: (1) related to situs viscerum and (2) of a neurobehavioral nature. We find little evidence linking these two groups, which implies different developmental regulatory pathways and independent evolutionary histories for visceral and telencephalic lateralizations. Studies of animals other than standard model species are essential to test hypotheses about the evolution of laterality in amphibians and other chordates. BioEssays 26:512–522, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

A number of commentators agree that the evidence reviewed in the target article supports a previously unrecognized role for ovarian hormones in feminization of the brain. Others question this view, suggesting that the traditional model of sexual differentiation already accounts for ovarian influence. This position is supported by various reinterpretations of the data presented (e.g., ovarian effects are secondary to the presence/absence of androgen, ovarian effects are smaller than testicular effects, ovarian effects are not organizational). We discuss these issues, and (...) reiterate our position that evidence of neurobehavioral ovarian effects is incompatible with the currently accepted model of sexual differentiation. Other points regarding species generalizations, the direct versus indirect action of estrogen, and nonhormonal mechanisms of sexual differentiation are also discussed. Finally, we address the controversial issue of using ratio scores in the assessment of the human corpus callosum (where CC scores are divided by an index of brain size). Future applications to human research are also discussed. (shrink)

Dietary fiber and prebiotics consistently modulate microbiota composition and function and hence may constitute a powerful tool in microbiota-gut-brain axis research. However, this is largely ignored in Hooks et al.’s analysis, which highlights the limitations of probiotics in establishing microbiome-mediated effects on neurobehavioral functioning and neglects discussing the potential of prebiotics in warranting the microbiota's role in such effects.

J. G. Taylor advances an empirically testable local neural network model to understand the neural correlates of phenomenal experience. Taylor's model is better able to explain the presence and unity of phenomenal consciousness which support the idea that consciousness is coherent, undivided, and centered. However, Taylor fails to offer a satisfactory explanation of the nonlinear relationship between local and global neural systems. In addition, the ontological assumptions that PE is immediate, intrinsic, and incorrigible limit an understanding of the different experiential (...) forms consciousness takes during neurobehavioral development. Recent studies suggest that neurobehavioral development is discontinuous and that judgment emerges under conditions of uncertainty to render feeling and perception in equivalent terms of energy and behavior. Approaching the problem of phenomenal experience from a developmental perspective may help resolve the paradox of feeling infinitely close as well as distant from one's self. (shrink)

J. G. Taylor advances an empirically testable local neural network model to understand the neural correlates of phenomenal experience. Taylor's model is better able to explain the presence (i.e., persistence, latency, and seamlessness) and unity of phenomenal consciousness which support the idea that consciousness is coherent, undivided, and centered. However, Taylor fails to offer a satisfactory explanation of the nonlinear relationship between local and global neural systems. In addition, the ontological assumptions that PE is immediate, intrinsic, and incorrigible limit an (...) understanding of the different experiential forms consciousness takes during neurobehavioral development. Recent studies suggest that neurobehavioral development is discontinuous and that judgment emerges under conditions of uncertainty to render feeling and perception in equivalent terms of energy and behavior. Approaching the problem of phenomenal experience from a developmental perspective may help resolve the paradox of feeling infinitely close as well as distant from one's self. (shrink)