Anxiety in rats selectively bred for Fast and Slow kindling rates: situation-specific outcomes

Rats selectively bred for amygdala excitability, realized by fast or slow kindling epileptogenesis, were previously reported to exhibit differential levels of anxiety. Although the Slow kindling rats generally appeared more anxious in several behavioral tests, under certain test conditions the Fast kindling rats displayed greater anxiety or stressor reactivity. The present investigation confirmed that in a test of anxiety comprising suppression of consumption of a palatable snack in an unfamiliar environment, the Slow kindling rats exhibited greater anxiety and that this effect was attenuated by diazepam. Likewise, the acoustic startle response was greater in the Slow kindling rats. However, the fear-potentiated startle response was more pronounced in Fast kindling rats, particularly among females, irrespective of whether the test parameters elicited moderate or high startle amplitudes. The elevated startle in the Slow rats, and the fear potentiated startle in the Fast rats, were attenuated by diazepam. These data indicate the need to differentiate subtypes of anxiety in animal models, and raise the issue that anxiety elicited by specific environmental triggers may interact with genetically determined trait characteristics.     

Effects of processing speed on cerebral asymmetry for left- and right-oriented faces

A free-vision chimeric facial emotion judgment task and a tachistoscopic face-recognition reaction time task were administered to 20 male right-handed subjects. The tachistoscopic task involved judgments of whether a poser in the centrally presented full-face photograph was the same or different poser than in a profile photograph presented in the left or right visual field (LVF, RVF). The free-vision task was that used by J. Levy, W. Heller, M. Banich, and L. Burton (1983, Brain and Cognition, 2, 404-419) and involved judging which of two chimeric faces appeared happier, in which the two chimeras were mirror images of each other and each chimera consisted of a smiling half-face joined at the midline to a neutral half-face of the same poser. For the tachistoscopic task, subjects were divided into groups of Fast and Slow responders by a median split of the mean reaction times. For the Fast subjects, judgments were faster in the LVF than in the RVF, and there was a significant interaction between visual field and profile direction, such that responses were faster for medially oriented profiles; i.e., LVF responses were faster for right-facing than for left-facing profiles, with the reverse relationship in the RVF. The Slow responders did not show these effects. Only the Fast group showed the bias for choosing the chimera with the smile on the left as happier, and mean response speed and the LVF advantage on the tachistoscopic test correlated with the leftward bias on the free-vision task for all subjects combined. It was suggested that overall response speed on the face-matching task reflected the extent to which specialized and more efficient right hemisphere functions were activated.     

Properties of internal speed control and psychophysiological response during continuous forearm rotation movement.

This study investigated the properties of speed control and psychophysiological response when subjects changed movement speed internally. The task consisted of a continuous forearm rotational movement, which 14 women performed under 3 conditions, namely, (1) Preferred: the subject performed the task at a freely selected speed, (2) Slow: the subject changed the speed in two steps from preferred to a slower pace (slow, then very slow), (3) Fast: the subject changed the speed in two steps from preferred to a faster pace (fast, then very fast). Rotation speed and the coefficient of variation were measured to evaluate within-subject variability. Under the Preferred condition, there were no significant differences in rotation speed or coefficient of variation during the trials. However, under Slow and Fast conditions, the standard variation scores and coefficient of variation indicated different tendencies. Under the Fast condition, although the standard variation increased with the faster speed, the coefficient of variation decreased. On the other hand, the coefficient of variation increased under the Slow condition. Preferred speed had a significant positive relationship to the slow, very slow, fast, and very fast speeds. Heart rate (R-R interval) and EEG spectral intensity measurements showed no significant changes among the three conditions: however, respiration frequency significantly increased during Fast as compared to Preferred and Slow conditions. These results suggest that a preferred speed for continuous movement exists and that it is closely related to internal speed control as a psychological criterion. Furthermore, different movement speeds may reflect different psychophysiological responses.     

Comparing Holographic Reprocessing and Prolonged Exposure for Women Veterans with Sexual Trauma: A Pilot Randomized Trial

This pilot study compares an emerging evidence-based treatment, holographic reprocessing (HR) to prolonged exposure (PE) versus a person-centered (PC) control group to treat symptoms of distress in female Veterans with sexual trauma. In contrast to PE, HR does not include exposure to a target event of trauma. Instead, HR focuses on healing the internal working model or type of attachment style that may form as a result of interpersonal trauma or maltreatment. The model reveals how people perceive themselves and others. These perceptions set in motion emotional, cognitive, and behavioral tendencies wherein people unconsciously replicate similar types of relationships that reinforce their worldview. Fifty-one female Veterans with sexual trauma were randomly assigned to one of three treatments and completed pre- and post-treatment measures of psychiatric symptoms (anxiety, depression, and PTSD) and post-traumatic cognitions. ANOVAs found significant decreases on all variables. Post-hoc comparisons revealed that HR and PE treatments demonstrated significantly greater decreases in symptoms compared to the PC control group. Chi square analyses revealed that HR produced a significantly lower dropout rate 1 (6 %) compared to PE 7 (41 %) and PC 6 (35 %). These initial results are promising and further investigation of HR is warranted.     

The use of a self-control package to enhance temporal generality of a parent training program

The purpose of the present study was to examine the effectiveness of a self-control package in enhancing temporal generality of a parent training program. Sixteen mothers and their clinic-referred noncompliant children were assigned to either a parent training alone group, or a parent training plus self-control group. All mother-child dyads were treated individually by teaching the mother to reward compliance and other prosocial behavior, and to use time-out for noncompliance. In addition, mothers who also received self-control training learned to self-monitor their use of their new parenting skills and to reinforce themselves for use of the skill during a 2 month follow-up period. Assessment consisted of four home observations by independent observers prior to treatment, after treatment, and at a 2 month follow-up. The data indicated that the children in the parent training plus self-control group were significantly more compliant and less deviant at the 2 month follow-up than the children in the parent training alone group. Parental behavior did not differ between the two groups at the follow-up.     

Tests that discriminate between dyslexic and other learning-disabled boys

Dyslexic and nondyslexic boys within a single community's learning-disabled class were given a set of tests; performance on each of these tests has been reported to be significantly impaired in other dyslexic children compared to learning-disabled and normal groups. Linear discriminant function analysis revealed that error types rather than levels of performance best separated the carefully matched learning-disabled groups. Slow naming and high percentage of “dysphasic” errors characterized dyslexic boys. Visual temporal-spatial matching and “configuration-deficient” perceptual errors characterized the adequate readers who have other learning disabilities.     

Pavlovian heart rate and jaw movement conditioning in the rabbit: effects of medial prefrontal lesions

An experiment was conducted in which jaw movements (JM) and heart rate (HR) were concomitantly assessed in rabbits during simple Pavlovian conditioning. A 2-s 1200-Hz tone was the conditioned stimulus (CS) and an intraoral 1-cc pulse of 0.5 M sucrose-water solution was the unconditioned stimulus (US). Sham and medial prefrontal (mPFC)-lesioned animals received paired CS/US training with a 70- to 75-dB CS and were compared with sham- and mPFC-lesioned animals that received explicitly unpaired CS/US presentations. The percentages of JM CRs were significantly greater in the paired than the unpaired groups, but mPFC lesions had no effect on this measure. Conditioned HR decelerations occurred only in the paired groups and then only during the first session of training. Moreover, these CS-evoked cardiac decelerations were somewhat attenuated by the mPFC lesion. CS-evoked HR accelerations, which were significantly greater in unpaired than in paired animals, occurred during the four subsequent sessions. These results suggest that a CS-evoked cardioinhibitory process, mediated by the mPFC, is engendered by Pavlovian appetitive conditioning, as has been previously demonstrated for aversive conditioning. However, during JM conditioning these inhibitory changes are quickly replaced by tachycardia, possibly related to increased nonspecific somatomotor activity, since the tachycardia was somewhat greater in the unpaired animals.     

Neuromuscular responses to platform perturbations in power- versus endurance-trained athletes

The purpose was to assess differences in postural response characteristics between two groups of elite athletes having power or endurance training. Participants were all men and included power- (M age = 21 yr., SD = 3, n = 12) and endurance-trained (M age = 22, SD = 3, n = 12) athletes. Muscle response characteristics and center of pressure measures were recorded during recovery from Fast (10 cm at 80 cm/sec.) and Slow (10 cm at 20 cm/sec.) horizontal platform perturbations. In response to Fast perturbations, power-trained athletes responded with significantly shorter times to stabilize the center of pressure, shorter muscle-contraction onset times, and larger muscle response amplitudes than endurance-trained athletes. This suggests power-trained athletes are more effective than endurance-trained athletes in responding to balance threats such as slips and trips in daily life and that power training should be studied to improve balance control of balance-impaired populations.     

Anabolic-androgenic steroids: effects on social behavior and baseline heart rate

Examined the effects of anabolic-androgenic steroids (AS) on behavior, baseline heart rate (HR), and stress-induced HR responses. Twenty-four cynomolgus monkeys were assigned to four mixed social groups of both AS and sham control animals. For 2 months, AS-treated monkeys received biweekly injections of testosterone, and, on an identical schedule, the control animals were injected with a sham solution. Behavioral data revealed that AS disrupted the social milieu such that all dominant animals exhibited increases in dominant behavior and subordinates manifested increased submission. These changes returned to pretest levels 8 weeks following termination of the drug intervention. Affiliative behaviors decreased on the part of all animals as a function of AS and, with the exception of play behavior, failed to return to pretest levels after the 8-week period of recovery. AS created an increase in baseline HR, particularly among the dominant animals. Interestingly, the subordinate AS animals experienced a decrease in baseline HR response. AS had no apparent influence on stress-induced HR reactivity.     

Concomitant Pavlovian conditioning of heart rate and leg flexion responses in the rat

Pavlovian conditioning was studied in male Fischer 344 rats using tones as the conditioned stimulus (CS) and footshock as the unconditioned stimulus (UCS). Different groups of animals received (a) contiguous CS-UCS pairings with a 0.5 sec CS, (b) contiguous CS-UCS pairings with a 4.0 sec CS, or (c) a random sequence of noncontiguous tones and shocks using either a 0.5 sec or a 4.0 sec CS. Heart rate (HR) and leg flexion (LF) responses were recorded. Leg flexion conditioning occurred only in the 0.5 sec contiguous group. Decelerative HR CRs occurred only in the 4.0 sec contiguous group. Accelerative HR changes occurred in the other two groups but were significantly greater in the 0.5 sec contiguous group. These results are similar to but not identical to those obtained during eyeblink or nictitating membrane conditioning in rabbits, and suggest that the topography of the Pavlovian HR CR is dependent on the simultaneous occurrence of other classically conditioned responses.     

The effect of continuous, intermittent, and "placebo" reinforcement on the effectiveness of the conditioning treatment for enuresis nocturna

It has been suggested that intermittent reinforcement may be of value in reducing the rate of relapse in bedwetting conditioning therapy. An experiment was conducted with 30 enuretic boys to examine acquisition and extinction parameters of continuous (100%), intermittent (70% variable ratio), and “placebo” (0%) reinforcement schedules. Reinforced trials were administered as in the typical Mowrer conditioning procedure. Non-reinforced trials were achieved by means of a time delay with the subsequent alarm being activated in the parent's room rather than in the child's room. These procedures required the development of a new conditioning device which could be programmed to automatically administer the desired schedule of reinforcement. The results of the field investigation revealed that continuous reinforcement (CR) and intermittent reinforcement (IR) groups attained acquisition in approximately the same number of trials and with essentially the same success rate. Relapse rate was significantly greater in the CR group than in the IR group. The placebo group showed no improvement over the 6 weeks of treatment. The results of this study may be interpreted as supporting the tenet that relapse can be viewed and treated as an extinction of the acquired response.     

麻醉诱导期右美托咪定滴鼻在患儿中的镇静及躁动研究

探究麻醉诱导期右美托咪定滴鼻对患儿术中及术后的镇静效果。择期手术患儿60例,随机分为3组,D1组、D2组和C组,麻醉诱导期分别给予1.0μg/kg右美托咪定滴鼻,2.0μg/kg右美托咪定滴鼻和等量生理盐水滴鼻。结果三组滴鼻前时刻T0血流动力学无差异（P〉0.05）,滴鼻后45min时刻（T1）和拔出导管或喉罩时刻（T2）D1组与D2组较C组心率和血压低（P〈0.05）,但在允许范围内;T1、T2时刻,D1组与D2组差异不明显（P〉0.05）;术后躁动评分,D1组与D2组较C组低（P〈0.05）,D2组较D1组低（P〈0.05）;术后疼痛评分,D1组与D2组较C组低（P〈0.05）,D1组与D2组差异无统计学意义（P〉0.05）;术后镇痛需求,D1组与D2组较C组少（P〈0.05）;不良反应无差异（P〉0.05）。麻醉诱导期右美托咪定滴鼻起到有效镇静作用,减少麻醉苏醒期躁动,减轻疼痛。2.0μg/kg的右美托咪定剂量麻醉诱导期滴鼻减少术后躁动效果更明显,不增加不良反应的发生。     

Heart rate reactivity in attention deficit disorder subgroups.

Beat-to-beat heart rate (HR) was analyzed for 9 contiguous seconds in a warned reaction time (RT) paradigm. Imperative stimuli were tones of three intensity levels (55, 78, and 100 db); a visual warning signal occurred 5 sec before tone onset. Baseline and reward conditions were run. Normal controls were contrasted with three Attention Deficit Disorder (ADD) subgroups: ADD-only, ADD with hyperactivity (ADDH), ADD with hyperactivity and aggression (ADDHA). The ADD subgroups were predicted to show less deceleration in HR because of their problem sustaining readiness to respond. Significant sex x group differences in HR levels and change scores were found. Overall, girls had higher HR levels than boys and the ADD-only group (boys and girls) had lower HRs than the other ADD groups. But, the ADD-only boys had more marked deceleration to the warning signal and acceleration to the tones than the other ADD boys, whereas the ADD-only girls were no more reactive than the ADDH and ADDHA girls. Control girls had the highest HR levels and were the most reactive to stimuli. Control boys and ADD-only boys had similar HR levels and reaction patterns. ADD-only girls appear to be underaroused, whereas ADD-only boys do not. Results suggest that cardiac measures can provide external validation of disruptive and nondisruptive ADD subtypes.     

不同应激范式对大鼠行为和脑神经颗粒素含量的影响

为探讨慢性情绪应激、生理应激对大鼠旷场行为和脑神经颗粒素（Neurogranin,NG）含量的不同作用,以及NG含量变化与应激性行为效应之间的相互关系。分别以不确定性空瓶刺激和饮水剥夺,建立情绪应激和生理应激动物模型。将40只雄性SD大鼠随机分为情绪应激组（ES）、生理应激组（PS）、定时饮水组（C1）和正常对照组（C2）（n=10）。以旷场行为任务来评定大鼠应激后的行为变化,Western blotting方法测定海马和前脑皮层中的NG含量。结果表明：应激后四组大鼠海马的NG含量差异无显著性;ES组前脑皮层的NG含量低于C2组,差异具有显著性,p<0.01;PS组的前脑皮层NG含量也下降,但与C2组相比差异无显著性; 应激后ES组、PS组修饰行为多于C2组,差异具有显著性,分别为p<0.01,p<0.05;前脑皮层NG含量与修饰行为之间的相关达显著水平。提示慢性情绪和生理应激均能导致前脑皮层NG含量下降,修饰行为增加,情绪应激作用更显著。修饰行为可能是反映情绪状态的较敏感行为指标,前脑皮层NG水平可能是预测情绪应激所致焦虑或抑郁行为的较敏感生物学指标。     

Trauma in Resettled Iraqi Refugees: Differences between Those Seeking Psychological Treatment and Those Not Seeking Psychological Treatment

Psychological distress experienced by resettling refugees has been well documented, with posttraumatic stress disorder (PTSD) and depression being prevalent outcomes. This study examined psychological and physiological measures of trauma exposure in 2 groups of Iraqi refugees resettled in Australia, those seeking psychological treatment (n = 25) versus those not seeking treatment (n = 22). Data from a group of healthy sex- and age-matched controls (n = 32) were collected to facilitate norm comparisons for physiological arousal. Continuous recording of electrocardiogram data examined resting heart rate (HR). Refugees seeking treatment had significantly higher levels of PTSD symptomology and depression levels compared to non-treatment-seeking refugees; however, there was no difference in the number of trauma events endorsed. Finally, resting HR was significantly higher in both refugee groups compared with healthy controls; however, there was no difference between the refugee groups. Clinical consideration of this excessive trauma exposure and elevated autonomic arousal is warranted.     

Self-efficacy and affect responses to Sprint Interval Training

ObjectivesTo examine the influence of efficacious beliefs on affective states, enjoyment, and satisfaction after performing a maximal intensity exercise task (i.e. Sprint Interval Training (SIT).DesignAn experimental design was utilized and participants were randomized to a high self-efficacy feedback (HE), low self-efficacy feedback (LE), or no feedback control condition.MethodsCollege-aged men and women (n = 74) performed four 30-second maximal sprints, interspersed with 4-min breaks. Following each sprint interval, participants received either positive, negative or no feedback and SIT self-efficacy, affective states (i.e., positive well-being, psychological distress, fatigue), heart rate (HR), and ratings of perceived exertion (RPE) were assessed. Upon terminating the exercise session, enjoyment and satisfaction were assessed.ResultsThere was group equivalency in HR and RPE among participants of each group. The HE group had significantly less of a decline in SIT self-efficacy from pre to post SIT than both the LE and control groups, and reported significantly higher levels of exercise enjoyment than the other two groups. In addition, the HE and control groups reported significantly higher satisfaction than the LE group.ConclusionsWe recommend that exercisers receive positive feedback statements while performing SIT to minimize the decrease in SIT self-efficacy and to bolster feelings of enjoyment and satisfaction.     

Heart rate reactivity in attention deficit disorder subgroups

Beat-to-beat heart rate (HR) was analyzed for 9 contiguous seconds in a warned reaction time (RT) paradigm. Imperative stimuli were tones of three intensity levels (55, 78, and 100 db); a visual warning signal occurred 5 sec before tone onset. Baseline and reward conditions were run. Normal controls were contrasted with three Attention Deficit Disorder (ADD) subgroups: ADD-only, ADD with hyperactivity (ADDH), ADD with hyperactivity and aggression (ADDHA). The ADD subgroups were predicted to show less deceleration in HR because of their problem sustaining readiness to respond. Significant sex x group differences in HR levels and change scores were found. Overall, girls had higher HR levels than boys and the ADD-only group (boys and girls) had lower HRs than the other ADD groups. But, the ADD-only boys had more marked deceleration to the warning signal and acceleration to the tones than the other ADD boys, whereas the ADD-only girls were no more reactive than the ADDH and ADDHA girls. Control girls had the highest HR levels and were the most reactive to stimuli. Control boys and ADD-only boys had similar HR levels and reaction patterns. ADD-only girls appear to be underaroused, whereas ADD-only boys do not. Results suggest that cardiac measures can provide external validation of disruptive and nondisruptive ADD subtypes.     

Behavioral and physiological correlates of aggressive dominance in male brown lemmings (Lemmus sibiricus)

Naive male brown lemmings were paired with the same opponent for 10 min/day for 11 consecutive days. Males of a control group were placed in an empty arena for the same period. There was no decrement in the incidence of attack and chase by dominant males in pairs showing stable dominant-subordinate relations. Subsequently, seminal vesicles of dominant animals were heavier than those of subordinate, control and “no rank” (pairs in which no clear-cut dominance relations were established) animals. Dominant animals also had greater mean testis weights and higher plasma testosterone levels than subordinates. Adrenal weights did not differ significantly between the various groups. Among dominant males there were significant positive correlations between plasma testosterone levels, testis and seminal vesicle weights, and attack and chase scores. These results suggest that many of the physiological correlates of dominance status reported in previous studies in which subjects were group housed are also observed when contact between naive individuals is limited to brief encounters.     

Perceived susceptibility and self-protective behavior: a field experiment to encourage home radon testing

Tested in a field experiment (N = 647) the hypothesis that perceptions of personal susceptibility are important in decisions to test one's home for radioactive radon gas. Experimental group subjects received a personal telephone call to tell them they lived in a high-risk area and a personal letter to reinforce the telephone message. After the intervention, experimental subjects were significantly more likely than minimal-treatment subjects to acknowledge the possibility of high radon levels in their homes. Perceptions of susceptibility and illness severity were significantly correlated with orders of radon test kits and with testing intentions. Nevertheless, there were no differences between groups in test orders or intentions. Results are discussed in terms of the difficulty of getting people to acknowledge susceptibility and the factors other than risk perceptions that influence self-protective behavior.     

Posttraining prefrontal lesions impair jaw movement conditioning performance,but have no effect on accompanying heart rate changes

This experiment examined the role of the medial prefrontal cortex (mPFC) in regulating learned autonomic and somatomotor responses in rabbits using appetitive Pavlovian conditioning. Interstimulus interval (ISI) duration [i.e., the time between the onset of the conditioned stimulus (CS) and unconditioned stimulus (US)] was manipulated in order to determine whether ISI duration was related to the heart rate (HR) responses obtained during conditioning. Two groups received either a 1- or a 4-s ISI, with a tone as the CS and an intraoral pulse of water as the US. Another two groups received explicitly unpaired presentations of either the 1- or 4-s tone CS and water US. Few conditioned jaw movement (JM) or HR conditioned responses (CRs) were observed in the unpaired conditions. Significant JM conditioning was, however, elicited by the paired conditions, especially to the 4-s ISI. Consistent CS-evoked HR accelerations were observed in both ISI conditions. After five sessions of training, the mPFC was lesioned in half the animals. A separate group of paired animals received sham lesions. After surgical recovery, all animals received 3 days of postoperative training. During the first postoperative training session, JM CRs significantly declined in both groups with mPFC lesions in comparison to the groups with sham lesions. The mPFC lesions, however, did not affect the CS-evoked cardiac accelerations, which again occurred during postoperative training.