Increased brain serotonin turnover in panic disorder patients in the absence of a panic attack: reduction by a selective serotonin reuptake inhibitor

Since the brain neurotransmitter changes characterising panic disorder remain uncertain, we quantified brain noradrenaline and serotonin turnover in patients with panic disorder, in the absence of a panic attack. Thirty-four untreated patients with panic disorder and 24 matched healthy volunteers were studied. A novel method utilising internal jugular venous sampling, with thermodilution measurement of jugular blood flow, was used to directly quantify brain monoamine turnover, by measuring the overflow of noradrenaline and serotonin metabolites from the brain. Radiographic depiction of brain venous sinuses allowed differential venous sampling from cortical and subcortical regions. The relation of brain serotonin turnover to serotonin transporter genotype and panic disorder severity were evaluated, and the influence of an SSRI drug, citalopram, on serotonin turnover investigated. Brain noradrenaline turnover in panic disorder patients was similar to that in healthy subjects. In contrast, brain serotonin turnover, estimated from jugular venous overflow of the metabolite, 5-hydroxyindole acetic acid, was increased approximately 4-fold in subcortical brain regions and in the cerebral cortex (P < 0.01). Serotonin turnover was highest in patients with the most severe disease, was unrelated to serotonin transporter genotype, and was reduced by citalopram (P < 0.01). Normal brain noradrenaline turnover in panic disorder patients argues against primary importance of the locus coeruleus in this condition. The marked increase in serotonin turnover, in the absence of a panic attack, possibly represents an important underlying neurotransmitter substrate for the disorder, although this point remains uncertain. Support for this interpretation comes from the direct relationship which existed between serotonin turnover and illness severity, and the finding that SSRI administration reduced serotonin turnover. Serotonin transporter genotyping suggested that increased whole brain serotonin turnover most likely derived not from impaired serotonin reuptake, but from increased firing in serotonergic midbrain raphe neurons projecting to both subcortical brain regions and the cerebral cortex.     

Friendships and Romantic Relationships of Black and White Adolescents

Prior research on adolescent peer relationships has focused on interpersonal dimensions of friendships but not of romantic relationships, and has rarely examined minority groups. We used a random sample of 122 adolescents to examine race and gender differences in friendships, romantic relationships, and the congruence between closest friendship and romantic relationship on five interpersonal domains: mutual support, self-disclosure, hurtful conflict, fear of betrayal, and interpersonal sensitivity. Significant race by gender differences in the difference between relationship type for both positive and negative dimensions of relationships were found. White girls reported significantly higher levels of self-disclosure in their friendship ties in comparison to romantic relationship, whereas white boys reported nearly equivalent levels. In comparison to white adolescents, Black adolescent girls and boys had similar levels of self-disclosure in their romantic relationships as their same-sex friendships. With regards to negative elements of relationships, girls reported more hurtful conflict in romance than friendship, whereas boys reported an opposite pattern. Results highlight the importance of consideration of race and gender influences on youth interpersonal skills within peer and romantic relationships.     

Onset of illusory figures attenuates change blindness

We examined whether the onset of a new object defined by illusory contours is detected with greater frequency than offset when neither is associated with a unique sensory transient. Observers performed a “one-shot” change detection task in which offsetting or onsetting elements of high luminance contrast circles generated the appearance or disappearance of a Kanizsa figure. Presenting “illusory figures” via this “flicker” method ensures that (1) any unique luminance transients associated with the two types of change are eliminated, and (2) the objects themselves can only be represented at a relatively high level. Results showed that offsets were detected more frequently than onsets only when they generated the onset of a Kanizsa figure. We argue that object appearance dominates object disappearance via mechanisms that operate at the level at which objects are constructed.     

Opioid receptors mediate direct predictive fear learning: evidence from one-trial blocking

Pavlovian fear learning depends on predictive error, so that fear learning occurs when the actual outcome of a conditioning trial exceeds the expected outcome. Previous research has shown that opioid receptors, including μ-opioid receptors in the ventrolateral quadrant of the midbrain periaqueductal gray (vlPAG), mediate such predictive fear learning. Four experiments reported here used a within-subject one-trial blocking design to study whether opioid receptors mediate a direct or indirect action of predictive error on Pavlovian association formation. In Stage I, rats were trained to fear conditioned stimulus (CS) A by pairing it with shock. In Stage II, CSA and CSB were co-presented once and co-terminated with shock. Two novel stimuli, CSC and CSD, were also co-presented once and co-terminated with shock in Stage II. The results showed one-trial blocking of fear learning (Experiment 1) as well as one-trial unblocking of fear learning when Stage II training employed a higher intensity footshock than was used in Stage I (Experiment 2). Systemic administrations of the opioid receptor antagonist naloxone (Experiment 3) or intra-vlPAG administrations of the selective μ-opioid receptor antagonist CTAP (Experiment 4) prior to Stage II training prevented one-trial blocking. These results show that opioid receptors mediate the direct actions of predictive error on Pavlovian association formation.     

Body in Mind: The Role of Embodied Cognition in Self-Regulation

We review a growing body of literature that evidences the reciprocal relationship between body and mind, known as embodied cognition. We argue that an embodied mind may serve a functional purpose, aiding in self-regulatory processes. Specifically, we suggest that embodied cognition assists in self-regulation by increasing signal strength, encouraging appropriate goal-relevant action, and incorporating situational constraints to cue appropriate information processing styles. Furthermore, we propose that affect serves as the link between an embodied mind and self-regulatory action. Finally, we situate this research in debates on theories of mind, and we advocate for a highly interactive system that integrates information across modalities.     

Recruiters’ Inferences of Applicant Personality Based on Resume Screening: Do Paper People have a Personality?

Research shows recruiters infer dispositional characteristics from job applicants’ resumes and use these inferences in evaluating applicants’ employability. However, the reliability and validity of these inferences have not been empirically tested. Using data collected from 244 recruiters, we found low levels of estimated interrater reliability when they reviewed entry-level applicants’ resumes and made inferences regarding applicants’ personality traits. Moreover, when recruiters’ inferences of applicant personality were correlated with applicants’ actual Big Five personality scores, results indicated that recruiters’ inferences lacked validity, with the possible exceptions of extraversion and openness to experience. Finally, despite being largely unreliable and invalid, recruiters’ inferences of applicants’ extraversion, openness to experience, and conscientiousness predicted the recruiters’ subsequent employability assessments of the applicants.     

What Do We Know About Neuropsychological Aspects Of Schizophrenia?

Application of a neuropsychological perspective to the study of schizophrenia has established a number of important facts about this disorder. Some of the key findings from the existing literature are that, while neurocognitive impairment is present in most, if not all, persons with schizophrenia, there is both substantial interpatient heterogeneity and remarkable within-patient stability of cognitive function over the long-term course of the illness. Such findings have contributed to the firm establishment of neurobiologic models of schizophrenia, and thereby help to reduce the social stigma that was sometimes associated with purely psychogenic models popular during parts of the 20th century. Neuropsychological studies in recent decades have established the primacy of cognitive functions over psychopathologic symptoms as determinants of functional capacity and independence in everyday functioning. Although the cognitive benefits of both conventional and even second generation antipsychotic medications appear marginal at best, recognition of the primacy of cognitive deficits as determinants of functional disability in schizophrenia has catalyzed recent efforts to develop targeted treatments for the cognitive deficits of this disorder. Despite these accomplishments, however, some issues remain to be resolved. Efforts to firmly establish the specific neurocognitive/neuropathologic systems responsible for schizophrenia remain elusive, as do efforts to definitively demonstrate the specific cognitive deficits underlying specific forms of functional impairment. Further progress may be fostered by recent initiatives to integrate neuropsychological studies with experimental neuroscience, perhaps leading to measures of deficits in cognitive processes more clearly associated with specific, identifiable brain systems.     

Impaired embodiment and intersubjectivity

This paper considers the importance of the body for self-esteem, communication, and emotional expression and experience, through the reflections of those who live with various neurological impairments of movement and sensation; sensory deafferentation, spinal cord injury and Möbius Syndrome (the congenital absence of facial expression). People with severe sensory loss, who require conscious attention and visual feedback for movement, describe the imperative to use the same strategies to reacquire gesture, to appear normal and have embodied expression. Those paralysed after spinal cord injury struggle to have others see them as people rather than as people in wheelchairs and have been active in the disability movement, distinguishing between their medical impairment and the social induced disability others project onto them. Lastly those with Möbius reveal the importance of the face for emotional expression and communication and indeed for emotional experience itself. All these examples explore the crucial role of the body as agent for social and personal expression and self-esteem.     

Physical fitness and self-reported physical exercise among college men and women in 1987 and 1997.

The study examined the relations of self-reported physical activity levels and physical fitness scores for two samples of college students assessed in 1987 (n = 261) and in 1997 (n = 243). Significantly greater exercise was reported by the 1997 women than the 1987 women; amount of exercise reported by men did not differ. For both samples, greater exercise was associated with increased fitness for women and men as assessed by the Hall 1986 Physical Fitness Test Profile, comprised of measures on body fat composition; grip strength; muscle endurance, flexibility, resting heart rate; systolic and diastolic blood pressures; and aerobic power. For the 1987 sample men were more fit than women. For the 1997 sample, women were more fit than men. The 1997 women were more fit than the 1987 women; there was no difference on overall fitness measures of the two samples of men.