Approach–avoidance generally describes appetitive motivation and fear of punishment. In a social context approach motivation is, however, also expressed as social aggression and dominance. We therefore link approach–avoidance to dominance–submissiveness, and provide a neural framework that describes how the steroid hormone testosterone shifts reflexive as well as deliberate behaviors towards dominance and promotion of social status. Testosterone inhibits acute fear at the level of the basolateral amygdala and hypothalamus and promotes reactive dominance through upregulation of vasopressin gene expression in the (...) central-medial amygdala. Finally, the hormone can, depending on social context and prenatal hormone exposure, promote both pro- and antisocial behaviors and decisions through its effects on prefrontal–amygdala interactions. All these effects of testosterone, however, serve to increase and maintain social status. (shrink)
Recent accounts on the global workspace theory suggest that consciousness involves transient formations of functional connections in thalamo-cortico-cortical networks. The level of connectivity in these networks is argued to determine the state of consciousness. Emotions are suggested to play a role in shaping consciousness, but their involvement in the global workspace theory remains elusive. In the present study, the role of emotion in the neural workspace theory of consciousness was scrutinized by investigating, whether unconscious and conscious display of emotional compared (...) to neutral facial expressions would differentially modulate EEG coherence. EEG coherence was measured by means of computing an average EEG coherence value between the frontal, parietal, and midline scalp sites. Objective awareness checks evidenced that conscious identification of the masked facial expressions was precluded. Analyses revealed reductions in EEG coherence in the lower frequency range for the masked as compared to unmasked neutral facial expressions. Crucially, a decline in EEG coherence was not observed for the emotional facial expressions. In other words, the level of EEG coherence did apparently vary as a function of awareness, but not when emotion was involved. The current finding suggests that EEG coherence is modulated by unconscious emotional processes, which extends common views on the global workspace architecture of consciousness. (shrink)
Transcranial magnetic stimulation (TMS) is a method capable of transiently modulating neural excitability. Depending on the stimulation parameters information processing in the brain can be either enhanced or disrupted. This way the contribution of different brain areas involved in mental processes can be studied, allowing a functional decomposition of cognitive behavior both in the temporal and spatial domain, hence providing a functional resolution of brain/mind processes. The aim of the present paper is to argue that TMS with its ability to (...) draw causal inferences on function and its neural representations is a valuable neurophysiological tool for investigating the causal basis of neuronal functions and can provide substantive insight into the modern interdisciplinary and (anti)reductionist neurophilosophical debates concerning the relationships between brain functions and mental abilities. Thus, TMS can serve as a heuristic method for resolving causal issues in an arena where only correlative tools have traditionally been available. (shrink)
Seeking to unlock the secrets of consciousness, neuroscientists have been studying neural correlates of sensory awareness, such as meaningless randomly moving dots. But in the natural world of species' survival, “raw feelings” mediate conscious adaptive responses. Merker connects the brainstem with vigilance, orientating, and emotional consciousness. However, depending on the brain's phylogenetic level, raw feeling takes particular forms. (Published Online May 1 2007).
Mazur & Booth's (1998) target article concerns basal and reciprocal relations between testosterone and dominance, and has its roots in Mazur's (1985; 1994) model of primate dominance-submissiveness interactions. Threats are exchanged in these interactions and a psychological stress-manipulation mechanism is suggested to operate, making sure that face-to-face dominance contests are usually resolved without aggression. In this commentary, a recent line of evidence from human research on the relation between testosterone, cortisol, and vigilant (dominant) and avoidant (submissive) responses to threatening “angry” (...) faces is discussed. Findings, to a certain extent, converge with Mazur & Booth's theorizing. However, the strongest relations have been found in subliminal exposure conditions, suggesting that biological instead of psychological mechanisms are involved. (shrink)
Behrendt & Young (B&Y) propose an explanation for schizophrenia in terms of a cortical default in the interaction between consciousness and cognition. However, schizophrenia more likely involves miscommunication between subcortical and cortical affective circuits in the brain, a default in the interaction between consciousness and emotion. The typical “affective” nature of hallucinations in schizophrenia provides compelling evidence for subcortical involvement.
Insofar as South Africa underwent a rapid transformation from apartheid to democracy, it may provide a unique laboratory for investigating aspects of revenge and forgiveness. Here we suggest that observations and data from South Africa are partially consistent with the hypotheses generated by MCullough and colleagues. At the same time, the rich range of revenge and forgiveness phenomena in real-life settings is likely to require explanatory concepts other than specialized modules and their computational outputs.
Lewis proposes a solution for bridging the gap between cognitive-psychological and neurobiological theories of emotion in terms of dynamic systems modeling. However, an important brain network is absent in his account: the neuroendocrine system. In this commentary, the dynamic features of the cross-talk between the hypothalamic-pituitary-adrenal (HPA) and gonadal (HPG) axes are discussed within a triple-balance model of emotion.
The relation between testosterone levels and aggressive behavior is well established. From an evolutionary viewpoint, testosterone can explain at least part of the sex differences found in aggressive behavior. This explanation, however, is mediated by factors such as prenatal testosterone levels and basal levels of cortisol. Especially regarding sex differences in aggression during adolescence, these mediators have great influence. Based on developmental brain structure research we argue that sex differences in aggression have a pre-pubertal origin and are maintained during adolescence. (...) Evidence of prenatal, adolescent, and adult levels of testosterone in relation to aggression taken together, support Archer's argument for sexual selection as the driver of sex differences in aggression. (shrink)