An on-line program to calculate respiratory sinus arrhythmia amplitude

A variety of evidence shows that the amplitude of respiratory sinus arrhythmia (RSA)—the peak-to-peak variations in heart rate caused by respiration—is a valid and reliable index of para-sympathetic cardiac control. An on-line program to calculate RSA amplitude on a breath-by-breath basis is described. The validity of the RSA amplitude values obtained through the computer pro-gram were tested in two studies. From the first one, the correlations between RSA amplitude and a set of cardiorespiratory variables, under both rest and auditory stimulation conditions, are reported. In the second study, the effect of atropine administration on the RSA amplitude, under both rest and mental load conditions, was examined. The results of both studies are con-gruent with predictions and suggest the usefulness of the software.     

Sensory and non-sensory factors and the concept of externality in obese subjects

9 obese and 9 normal subjects performed a psychophysical task in which food- or non-food-related stimuli were briefly flashed tachistoscopically at a speed and intensity near the visual threshold. A signal was presented on one-half the trials and noise only on the other one-half of the trials. Using signal detection theory methodology, separate measures of sensory sensitivity (d') and response bias (beta) were calculated. No differences were noted between obese and normal subjects on measures of sensory sensitivity but significant differences on response bias. Obese subjects had consistently lower response criteria than normal ones. Analysis for subjects categorized by whether they were restrained or unrestrained eaters gave findings identical to those for obese and normal. The importance of using a methodology that separates sensory and non-sensory factors in research on obesity is discussed.     

A program to assess baroreceptor cardiac reflex function

This paper describes a computer program for the noninvasive evaluation in the time domain of the part of the baroreceptor reflex that relates blood pressure to interbeat interval from spontaneous hemodynamic patterns in which the reflex is operating. The program obtains the sensitivity of the baroreceptor reflex (slope of the regression line between the interbeat interval and systolic blood pressure in msec/mmHg) and an index of the baroreceptor power to regulate cardiac activity. These statistics are obtained differentially both when the systolic blood pressure is increasing and when it is decreasing. The results obtained by using this software during a mental load task were compared with those obtained through spectral analysis.     

Emotional and behavioral problems in children of depressed mothers: a school-based study in Southern Brazil

The present study aimed to verify the association between maternal depression and emotional and behavioral problems in school children in Pelotas, Southern Brazil, considering that maternal depression increases children’s vulnerability for developing psychiatric disorders. This is a cross-sectional study with a school-based sample conducted between August 2015 and November 2016 and it is part of a major project entitled ‘Healthy Childhood in Context: A Multidisciplinary Investigation’. Schoolchildren aged between 7 and 8 years and one of their respective parents or a primary caregiver were included in the study. Maternal depression was assessed using the Mini International Neuropsychiatric Interview (MINI). The presence of emotional and behavioral problems in children was verified by the Strengths and Difficulties Questionnaire (SDQ) – parents version. Children of depressed mothers exhibited higher mean scores in all SDQ domains and in the total score when compared to children of non-depressed mothers. Lower socio-economic status was also associated with higher SDQ scores. Our results showed the effects of both maternal depression and poverty on children emotional and behavioral problems, which evidence the need for child mental health preventive care, and free quality assistance for both mothers and their children.     

GABA, glutamate, dopamine and serotonin transporters expression on forgetting

Notwithstanding several neurotransmission systems are frequently related to memory formation; forgetting process and neurotransmission systems or their transporters; the role of γ-aminobutyric acid (GAT1), glutamate (EACC1), dopamine (DAT) and serotonin (SERT) is poorly understood. Hence, in this paper western-blot analysis was used to evaluate expression of GAT1, EAAC1, DAT and SERT during forgetting in trained and untrained rats treated with the selective serotonin transporter inhibitor fluoxetine, the amnesic drug d-methamphetamine (METH) and fluoxetine plus METH. Transporters expression was determined in the hippocampus (HIP), prefrontal cortex (PFC) and striatum (STR). Results indicated that forgetting of Pavlovian/instrumental autoshaping was associated to up-regulation of GAT1 (PFC and HIP) and DAT (PFC) while SERT (HIP) was down-regulated; no-changes were observed in striatum. Methamphetamine administration did not affect forgetting at 216 h post-training but up-regulated hippocampal DAT and EACC, prefrontal cortex DAT and striatal GAT1 or EACC1. Fluoxetine alone prevented forgetting, which was associated to striatal GAT1 and hippocampal DAT up-regulation, but prefrontal cortex GAT1 down-regulation. Fluoxetine plus METH administration was also able to prevent forgetting, which was associated to hippocampal DAT, prefrontal cortex SERT and striatal GAT1, DAT or SERT up-regulation, but prefrontal cortex GAT1 down-regulation. Together these data show that forgetting provokes primarily hippocampal and prefrontal cortex transporters changes; forgetting represent a behavioral process hardly modifiable and its prevention could causes different transporters expression patterns.     

Predictive learning in nutrient-based flavor conditioning

This paper presents two experiments on nutrient-based flavor conditioning with rats as subjects and sucrose as the unconditioned stimulus (US). Experiment 1 was aimed at establishing an optimal control for conditioning, comparing simultaneous and serial presentations of a flavor and the US. The results showed that simultaneous, but not serial training, produced conditioning. Experiment 2 was designed to obtain evidence of summation as an index of both conditioned inhibition and predictive learning. Group Simultaneous received Pavlovian conditioned inhibition training during which flavor A was simultaneously paired with sucrose on excitatory trials (A+), and forming an unreinforced compound with flavor B on inhibitory trials (AB-). An independent excitor for the summation test was also trained by simultaneous pairings with sucrose (C+). In the control group (Blocked), the AB- trials were presented forming a block at the beginning of training to avoid a negative contingency-relationship with sucrose, and flavor A received serial rather than simultaneous pairing with sucrose (A --> +). On the summation test, only in group Simultaneous was consumption of the CB compound lower than that of flavor C alone, suggesting that, during training, flavor A activated an expectancy of the US occurrence.     

NMDA and muscarinic receptors of the nucleus accumbens have differential effects on taste memory formation

Animals recognize a taste cue as aversive when it has been associated with post-ingestive malaise; this associative learning is known as conditioned taste aversion (CTA). When an animal consumes a new taste and no negative consequences follow, it becomes recognized as a safe signal, leading to an increase in its consumption in subsequent presentations (attenuation of neophobia, AN). It has been shown that the nucleus accumbens (NAcc) has an important role in taste learning. To elucidate the involvement of N-methyl-D-aspartate (NMDA) and muscarinic receptors in the NAcc during safe and aversive taste memory formation, we administrated bilateral infusions of DL-2-amino-5-phosphonopentanoic acid (APV) or scopolamine in the NAcc shell or core respectively. Our results showed that pre-training injections of APV in the NAcc core and shell disrupted aversive but not safe taste memory formation, whereas pre-training injections of scopolamine in the NAcc shell, but not core, disrupted both CTA and AN. These results suggest that muscarinic receptors seem to be necessary for processing taste stimuli for either safe or aversive taste memory, whereas NMDA receptors are only involved in the aversive taste memory trace formation.     

Validity of Adolescent and Parent Reports on the Six-Item ADHD Self-Report Scale (ASRS-6) in Clinical Assessments of Adolescent Social Anxiety

Adolescents experiencing social anxiety often experience co-occurring attention-deficit/hyperactivity disorder (ADHD) symptoms. Yet, assessing for social anxiety poses challenges given the already time-consuming task of distinguishing social anxiety from other commonly co-occurring internalizing conditions (e.g., generalized anxiety, major depression). Assessors need short screening devices to identify socially anxious adolescents in need of intensive ADHD assessments. A six-item version of the ADHD Self-Report Scale (ASRS-6) was originally developed to identify adults who likely meet diagnostic criteria for ADHD, but its psychometric properties have yet to be examined among adolescents. We tested the psychometric properties of the ASRS-6 when administered in clinical assessments for adolescent social anxiety. Eighty-nine 14–15 year old adolescents and their parents (67.4% female; 62.1% African American; 30 Clinic-Referred; 59 Community Control) completed the ASRS-6, measures of adolescent social anxiety and depressive symptoms, and parent-adolescent conflict. Adolescent self-reported and parent-reported ASRS-6 positively related with scores from established measures of social anxiety, depressive symptoms, and parent-adolescent conflict. Further, adolescent self-reported (but not parent-reported) ASRS-6 scores significantly discriminated adolescents on referral status. Adolescent self-reported (but not parent-reported) ASRS-6 scores incrementally predicted social anxiety over-and-above depressive symptoms, which commonly co-occur with social anxiety. Conversely, parent-reported (but not adolescent self-reported) ASRS-6 scores incrementally predicted parent-adolescent conflict over-and-above depressive symptoms, which commonly co-occur with conflict. When assessing adolescent ADHD symptoms, adolescents’ and parents’ reports meaningfully vary in their links to validity indicators. As such, among adolescents assessed for social anxiety, clinical assessments of adolescent ADHD symptoms should include both parent reports and adolescent self-reports.