Trauma exposure is associated with increased context-dependent adjustments of cognitive control in patients with posttraumatic stress disorder and healthy controls

Recent evidence has suggested that posttraumatic stress disorder (PTSD) is associated with alterations in prefrontal-cortex-dependent cognitive processes (e.g., working memory, cognitive control). However, it remains unclear whether these cognitive dysfunctions are related to PTSD symptomatology or trauma exposure. Furthermore, regarding cognitive control, research has only focused on the integrity of selected control functions, but not their dynamic regulation in response to changing environmental demands. Therefore, the present study investigated dynamic variations in interference control, in addition to overall interference susceptibility and working memory (WM) performance in matched groups of 24 PTSD patients and 26 traumatized and 30 nontraumatized healthy controls. The Simon task was used to measure overall interference susceptibility and the flexible adjustment of cognitive control, on the basis of the occurrence of response conflicts (conflict adaptation effect). WM performance was assessed with the forward and backward digit span tasks. Since we have previously shown that trauma exposure per se is associated with reduced hair cortisol concentrations (HCC), we further explored whether PTSD/trauma-related cognitive alterations are related to HCC in proximal 3-cm hair segments. The results revealed that PTSD patients and traumatized controls showed significantly more pronounced conflict adaptation effects than nontraumatized controls. Moreover, the conflict adaptation effect was positively related to the number of lifetime traumatic events and the frequency of traumatization. The groups did not differ in overall interference susceptibility or WM performance. Exploratory analyses revealed no association between HCC and the observed cognitive differences. These results suggest that context-driven control adjustments constitute a sensitive correlate of trauma exposure, irrespective of PTSD.     

Assessment of cognitive control in psychopathic and normal prisoners

It has been suggested that psychopaths exhibit specific deficits in cognitive processes associated with frontal lobe functioning. There is also evidence which indicates that level of intelligence may influence expression of impulse control among psychopaths. The present study investigated these hypotheses by comparing groups of 44 psychopaths and 14 normal controls selected from a sample of incarcerated male felons using Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria. Dependent variables included several measures of cognitive flexibility, perseveration, and impulsiveness. Compared to normal controls, psychopaths showed no greater tendencies to persist in incorrect responding, disregard cues suggesting the need to modify behaviors, or proceed impulsively in problem solving. Level of intelligence was found to be a moderator variable influencing performance for psychopaths and normal controls. Results suggest that deficits in cognitive functioning are not necessarily characteristic of psychopaths across situations.     

Modifying children's orienting reactions instrumentally

Normal Ss' GSRs to visual stimuli habituated more slowly than retarded Ss' GSRs and were larger. During conditioning, normal Ss' GSRs increased in magnitude under nonresponse-contingent reinforcement but not under response-contingent reinforcement. Retarded children's GSRs increased in magnitude slightly under response-contingent reinforcement but not under nonresponse-contingent reinforcement. More Ss who received response-contingent reinforcement improved in their performance on the Seguin form board than got poorer; Ss who received reinforcement contingent on nonresponding did not show this differential tendency. The retarded Ss showed this effect substantially more than normals. Children who were merely tested twice but received no conditioning showed no differential tendency toward improved form board performance. It was concluded that normal and retarded children differ in their initial orienting reaction (OR) tendencies, particularly in the persistence of OR under repeated stimulation, and that instrumental conditioning of ORs mediates improved performance on complex tasks requiring attention to relevant stimulus dimensions.     

Aversive conditioning in the sociopath

Results of two experiments on differential conditioning of the skin conductance (SCR) in sociopaths and normal control subjects are described. In the first experiment it was found that an equal number of sociopaths and control subjects were aware of the conditioning contingency. However, only the normal subjects displayed reliable differential SCR conditioning. Sociopaths showed a dissociation between verbal learning and conditioning of a physiological change. The second experiment examined the differential conditioning of normal subjects and sociopaths in partial remission. The number of aware subjects in the two groups did not differ. Aware subjects in both groups showed differential SCR conditioning. Differential conditioning in sociopaths did not persist over trials as it did in control subjects. A deficiency in ACTH 4–10 as well as neurological dysfunctions were considered possible factors in the etiology of sociopathy. Further research on the relation of neuropeptides to the etiology and treatment of sociopathy is suggested.     

Cognitive control and the COMT Val158Met polymorphism: genetic modulation of videogame training and transfer to task-switching efficiency

The study investigated whether successful transfer of game-based cognitive improvements to untrained tasks might be modulated by preexisting neuro-developmental factors, such as genetic variability related to the catechol-O-methyltransferase (COMT)—an enzyme responsible for the degradation of dopamine. The COMT Val¹⁵⁸Met genotype may differentially affect cognitive stability and flexibility, and we hypothesized that Val/Val homozygous individuals (who possess low prefrontal dopamine levels) show more pronounced cognitive flexibility than Met/-carriers (who possess high prefrontal dopamine levels). We trained participants, genotyped for the COMT Val¹⁵⁸Met polymorphism on playing “Half-Life 2”, a first-person shooter game which has been shown to improve cognitive flexibility. Pre-training (baseline) and post-training measures of cognitive flexibility were acquired by means of a task-switching paradigm. As expected, Val/Val homozygous individuals showed larger beneficial transfer effects than Met/-carriers. Our findings support the idea that genetic predisposition modulates transfer effects and that playing first-person shooter games promotes cognitive flexibility in individuals with a suitable genetic predisposition.     

Acquisition and discrimination of appetitively and aversively conditioned heart rate responses in rhesus monkeys

This report describes the acquisition of a conditional heart rate response to both classical aversive and appetitive conditioning in eight rhesus monkeys(Macaca mulatta). The behavioral paradigm consisted of two discrete one minute tones followed by the corresponding unconditional stimuli,i.e., electric shock or Purina monkey chow. A third tone followed by neither food nor shock served as a discriminative stimulus (DS). The conditional heart rate responses developed in two phases. The first phase was characterized by similar responses to both conditional stimuli and the DS. Control heart rate rose during this period. During the second phase, control heart rate decreased (five animals), the DS response disappeared, and different conditional heart rate patterns to food and shock emerged. The existence of distinct conditional response patterns indicates probable differences in the autonomic nervous regulation of the heart during aversive and appetitive conditioning.     

Assessing pavlov’s impact on the American conditioning enterprise

In this article, the visibility of Pavlov and of Watson in American psychology are compared, and the periods of their respective influence are specified with greater precision than is afforded by merely impressionistic methods. The author also critically examines the possibility that the early history of the American classic-conditioning enterprise involved a succession of two phases: a Watsonian/speculative phase and a Pavlovian/empirical phase. In conclusion, the author assesses the possibility that the publication of Pavlov’sConditioned Reflexes (1927) “stimulated” scholarly work on Pavlovian conditioning, and finds this proposition lacking empirical support.     

Assessing performance upon abrupt awakening from naps during quasi-continuous operations

Quasi-continuous work settings often involve sleep loss and requirements to perform at unpredictable times. Napping may alleviate some of the sleep-loss problems, but it increases the risk that the person will have difficulty functioning upon abrupt awakening. This paper describes an experimental approach, techniques, and analyses for investigating performance upon abrupt awakening from 2 h naps placed near either the circadian peak (P) or trough (T) in body temperature and preceded by 6, 18, 30, 42, or 54 h of sleep deprivation. Five groups of healthy young adults performed quasi-continuously for 54 h and were permitted a 2-h nap at one of five times. Reaction time (RT) to answer a phone terminating the nap, subjective estimates, and performance of a brief, challenging cognitive task were related to nap-sleep parameters of each group. Sleep deprivation increased the amount of deep sleep in the naps, and this was associated with greater postnap cognitive performance decrements; subjective estimates were unaffected, and RT performance was related simply to stage of sleep prior to awakening. Circadian placement of the naps also modulated the postnap cognitive decrement: T naps produced greater cognitive decrements than P naps, even when the latter involved more prior sleep loss. These findings have both practical and theoretical significance for evaluating the awakening process, and would not have been possible without the approach, techniques, and procedures described.     

The skill of recognizing musical structures

In three experiments, musicians and nonmusicians were compared in their ability to discriminate musical chords. Pairs of chords sharing all notes in common or having different notes were played in succession. Some pairs of chords differed in timbre independent of their musical structures because they were played on different instruments. Musicians outperformed nonmusicians only in recognizing the same chord played on different instruments. Both groups could discriminate between instrument timbres, although musicians did slightly better than nonmusicians. In contrast, with chord structures not conforming to the rules of tonal harmony, musicians and nonmusicians performed equally poorly in recognizing identical chords played on different instruments. Signal detection analysis showed that musicians and nonmusicians set similar criteria for these judgments. Musicians' superiority reflects greater sensitivity to familiar diatonic chords. These results are taken as evidence that musicians develop perceptual and cognitive skills specific to the lawful musical structures encountered in their culture's music. Nonmusicians who lack this knowledge based their judgments on the acoustical properties of the chords.     

RWMODEL: A program in Turbo Pascal for simulating predictions based on the Rescorla-Wagner model of classical conditioning

A Turbo Pascal computer program is described that simulates the Rescorla-Wagner model of classical conditioning. The menu-driven program makes it possible to compute associative strengths for differential conditioning, conditioned inhibition, compound and contextual conditionings, trans-switching, and other designs.     

Social modulation of learning in rats

It is well known that emotions participate in the regulation of social behaviors and that the emotion displayed by a conspecific influences the behavior of other animals. In its simplest form, empathy can be characterized as the capacity to be affected by and/or share the emotional state of another. However, to date, relatively little is known about the mechanisms by which animals that are not in direct danger share emotions. In the present study, we used a model of between-subject transfer of fear to characterize the social interaction during which fear is transmitted, as well as the behavioral effects of socially transmitted fear. We found that (1) during social interaction with a recently fear-conditioned partner, observers and demonstrators exhibit social exploratory behaviors rather than aggressive behaviors; (2) learning and memory in a shock-motivated shuttle avoidance task are facilitated in rats that underwent a social interaction with a partner that had been fear conditioned; and (3) a brief social interaction with a recently fear-conditioned partner immediately before fear conditioning increases conditioned freezing measured on the next day. The observed effects were not due to a stress-induced increase in pain sensitivity or analgesia. Collectively, these data suggest that a brief social interaction with a cage mate that has undergone an aversive learning experience promotes aversive learning in an otherwise naïve animal. We argue that socially transferred fear is an adaptation that promotes defensive behavior to potentially dangerous situations in the environment.Human empathy can be defined as the ability to experience and share the thoughts and feelings of others (de Waal 2008). Obviously, this is a complex social phenomenon that, until recently, has received much attention from philosophers and psychologists rather than neuroscientists (Decety and Lamm 2006). However, in its simplest form, empathy can be characterized as the capacity to be affected by and/or share the emotional state of another (de Waal 2008). Tuning one''s emotional state to that of another increases the probability of similar behavior, which thereby allows rapid adaptation to environmental challenges (Hatfield et al. 1994). This social adaptation may be particularly important for emotions that signal a potential danger, such as fear. Although one can learn about potentially harmful stimuli by directly experiencing an aversive event, observation or interaction with a conspecific in danger and/or in pain may also provide information about threats in the environment. There is a vast literature on learning about direct danger (Maren 2001) as well as sharing emotions through observation (see, e.g., Church 1959; Langford et al. 2006; Olsson and Phelps 2007). However, relatively little is known about the mechanisms by which animals that are not in a direct danger share emotions.We have recently designed an experimental rat model of between-subject transfer of emotional information (Knapska et al. 2006). In this model, rats are housed in pairs and one member of the pair (the “demonstrator”) is removed and subjected to fear conditioning. After the fear-conditioning episode, the conditioned animal is allowed to interact with its naïve cage mate (the “observer”). We showed that the demonstrator''s fear is socially transferred to the observer, resulting in both rapid increase in exploratory behavior of the observer and a pattern of c-Fos activation in the observer''s amygdala that parallels that of the shocked demonstrators.These results suggest that the social interaction between the demonstrator and observer results in a transfer of information that promotes aversively motivated learning in the observer. However, the nature of the social interaction and how it comes to influence aversively motivated behavior is not known. Therefore, the present study aimed to characterize the behavior of both the demonstrators and observers during their social interaction and further characterize the nature of the influence of socially transmitted fear on aversively motivated learning and memory. We hypothesized that the social interaction between observers and demonstrators would result in a social transfer of fear that would promote learning and memory of both active defensive responses (avoidance) as well as defensive immobility (freezing). To test this hypothesis, we carried out five experiments that examined the nature of the social interaction between shocked demonstrators and observers (Experiment 1), the acquisition and retention of active avoidance (Experiment 2), and conditioned freezing (Experiment 3). Because it is not clear if social transfer effects can be observed among unfamiliar animals and to control for social buffering, we also compared the social transfer of fear in familiar and unfamiliar rats (Experiment 4). To control for the possible influence of different pain sensitivity thresholds in the observers paired with shocked demonstrators, we carried out pain tests (Experiment 5).     

Pavloviana inPsychology of the 20th Century: A special review

In the encyclopedicPsychology of the 20th Century three volumes are relevant to the work of I. P. Pavlov, his predecessors, contemporaries, and followers. Volume 1 (1976) provides an extensive account of the history of non-introspective, “objective” psychology. In Volume 4 (1977), examined in this review and consisting of sections on “Theories of Learning” and “Behavior Modification,” separate chapters are devoted to Pavlov’s life and work, and its continuation in the Soviet Union. Classical conditioning is considered in the context of S-R learning theories, interaction with operant conditioning, and development of behavior therapy. Additional materials are likely to be presented in Volume 6 (to be published) dealing with animal psychology, ethology, and physiological psychology.     

Learning deficits and activity changes: A partial laboratory model in postencephalitic rats for studies of brain damage

Rats ranging from 8–21 days of age were inoculated in the right cerebral hemisphere with St Louis encephalitis virus, Japanese B encephalitis virus, Murray Valley encephalitis virus. Mumps virus however, was injected at age one day. When very young rats were injected with these viral preparations, fatal encephalitis usually developed. Rats injected at ages of more than two weeks showed little or no clinical signs of infection. When inoculated at ages between these extremes, clinical disease developed in most rats but many survived. Physically most of these surviving animals appeared to be normal, but when tested at maturity in a rather complex maze, they showed a marked reduction in learning ability. Tilting-cage-type activity measurements taken overnight with the Murray Valley encephalitis group also indicated that most of the postinfectious rats were hyperactive. These data imply that such a laboratory model might be related to similar hyperactivity and learning disabilities seen in certain types of minimally brain damaged children. A viral-sex interaction often seen in earlier studies is also noted in our animals injected at younger ages.     

Observer Effects without Demand Characteristics: An Inductive Investigation of Video Monitoring and Performance

Purpose

The purpose of these two studies was to explore the relationship between video monitoring and quantity of performance in the absence of demand characteristics.

Design/methodology/approach

Data were gathered via two experiments involving business students working on a motor task. Participants were randomly assigned to the monitored and unmonitored conditions. Experiment 1 (n = 75) was inductive while Experiment 2 (n = 139) was partially inductive.

Findings

Experiment 1 showed that monitored participants’ performance was lower than that of unmonitored participants. Further, monitoring reduced outliers, increased interquartile variance, and normalized the distribution. Experiment 2 replicated the effect of monitoring on performance controlling for cognitive ability and emotions, demonstrated that negative emotions interacted with monitoring condition, and suggested that differences in performance were not due to cheating or variation in task-related strategies. We offer a grounded theory of video monitoring proposing that different implicit decision rules are activated when people are monitored as compared to when they are not monitored.

Implications

Future research needs to determine the extent to which our results extend to similar settings in the workplace and to other forms of observation. At this time, we believe organizations should carefully consider the consequences of electronic monitoring. Controlling expectations in the lab or workplace does not necessarily eliminate the independent effect of monitoring. Therefore, researchers must beware misinterpretation of effect sizes and overlooking the role of observation in their data.

Originality/value

These studies demonstrate that video monitoring can create observer effects in the absence of demand characteristics. Our inductive approach revealed the nature of the effects beyond mean differences and served as the basis for developing a testable theory of monitoring that goes beyond what was previously known.     

An evaluation of Unix in the psychology computer laboratory

Psychology users of the Unix operating system responded to questionnaire items concerning the use of Unix, the ease of learning and using Unix, and the value and quality of the system for their research needs. The data suggest that Unix is poor according to human-factors criteria, but good according to programming and systems criteria.     

Sex-specific cognitive–behavioural profiles emerging from individual variation in numerosity discrimination in <Emphasis Type="Italic">Gambusia affinis</Emphasis>

The relationship between an individual’s cognitive abilities and other behavioural attributes is complex, yet critical to understanding how individual differences in cognition arise. Here we use western mosquitofish, Gambusia affinis, to investigate the relationship between individual associative learning performance in numerical discrimination tests and independent measures of activity, exploration, anxiety and sociability. We found extensive and highly repeatable inter-individual variation in learning performance (r = 0.89; ICC = 0.89). Males and females exhibited similar learning performance, yet differed in sociability, activity and their relationship between learning and anxiety/exploration tendencies. Sex-specific multivariate behaviour scores successfully predicted variation in individual learning performance, whereas combined sex analyses did not. Female multivariate behaviour scores significantly predict learning performance across females (ρ = 0.80, p = 0.005) with high-performing female learners differentiated from female non-learners and low-performing learners by significant contributions of activity and sociability measures. Meanwhile, males of different learning performance levels (high-, low- and non-learners) were distinguished from each other by unique behavioural loadings of sociability, activity and anxiety/exploration scores, respectively. Our data suggest that despite convergence on learning performance, the sexes diverge in cognitive–behavioural relationships that are likely products of different sexual selection pressures.     

The nature of hemispheric specialization for prosody perception

Recent evidence suggests a relative right-hemispheric specialization for emotional prosody perception, whereas linguistic prosody perception is under bilateral control. It is still unknown, however, how the hemispheric specialization for prosody perception might arise. Two main hypotheses have been put forward. Cue-dependent hypotheses, on the one hand, propose that hemispheric specialization is driven by specialization for the non-prosody-specific processing of acoustic cues. The functional lateralization hypothesis, on the other hand, proposes that hemispheric specialization is dependent on the communicative function of prosody, with emotional and linguistic prosody processing being lateralized to the right and left hemispheres, respectively. In the present study, the functional lateralization hypothesis of prosody perception was systematically tested by instructing one group of participants to evaluate the emotional prosody, and another group the linguistic prosody dimension of bidimensional prosodic stimuli in a dichotic-listening paradigm, while event-related potentials were recorded. The results showed that the right-ear advantage was associated with decreased latencies for an early negativity in the contralateral hemisphere. No evidence was found for functional lateralization. These findings suggest that functional lateralization effects for prosody perception are small and support the structural model of dichotic listening.     

Transformational and Transactional Leadership and Followers’ Achievement Goals

Purpose

Achievement goals, or the standards of competence employees pursue in their work, have far-reaching consequences for employee and organizational functioning. In the current research, we investigated whether employees’ achievement goals can be predicted from their supervisor’s leadership style.

Design/Methodology/Approach

A multilevel study was conducted in which followers of 120 organizational leaders completed measures of their leader’s transformational leadership (focusing on individual needs and abilities, on intellectual development, and on a common team mission), transactional leadership (focusing on monitoring and achievement-related rewards), and their own mastery goals (aimed at learning, developing, and mastering job-relevant skills), and performance goals (aimed at doing better than others).

Findings

Group-level transformational leadership predicted followers’ mastery goals, whereas group-level transactional leadership predicted followers’ performance goals. Within-group differences in transformational leadership also predicted mastery goals.

Implications

These findings suggest that leadership style plays an important role in the achievement goals followers adopt. Organizations may promote transactional leadership in contexts requiring that employees outperform others. In contrast, in contexts requiring learning and development, organizations may promote transformational leadership.

Originality/Value

This research is the first to examine the relationships between leadership styles and specific follower goals, and the first to highlight the role of leadership as a social variable involved in employees’ adoption of achievement goals.     

Attitudes Towards Potentially Carrying the FMR1 Premutation: Before vs After Testing of Non-Carrier Females with Diminished Ovarian Reserve

Diminished ovarian reserve (DOR) and premature ovarian failure are associated with elevated FMR1 CGG repeat alleles. We assessed pretest attitudes about potentially carrying the FMR1 premutation (FXP) (>55 CGG repeats) among reproductive age women compared with attitudes after learning their non-carrier status. Ninety-two women with DOR, regular menses and no family history of Fragile X Syndrome underwent FMR1 testing and completed attitudinal questionnaires before (T1) and 3 months after learning the test results (T2). The analysis utilized signed rank tests and α?=?0.05. Very few women thought they were likely to have a FXP (6.6 %). More participants thought FMR1 premutations were “serious” at T2 (62.9 %) than at T1 (46.1 %, p?p?相似文献   

Cognitive performance during successive sustained physical work episodes

The effects of physical work (30% of \(\dot VO_2 \) max), sleep loss (3-h nap during a 48-h operation), continuous work (CW), and time of day on cognitive performance were assessed (by ANOVA) in this repeated-measures study comparing two groups (exercise/nonexercise) of healthy young men (N=22). Treadmill walking did not accentuate or attenuate sleep loss effects on performance; however, sleep loss alone did degrade visual vigilance and memory for words. Time-of-day fluctuations were found in choice reaction time, logical reasoning, and word memory. Visual vigilance for nonexercising subjects degraded sooner on the 2nd CW day than it did for exercising subjects. A 3-h nap at 0400 h after 1 17-h CW day was not immediately recuperative. These findings indicate that exercise at 30% of \(\dot VO_2 \) max does not compound sleep-loss effects in cognitive performance. Indeed, physical activity during video terminal monitoring may delay any sleep-loss decrement. Variability of many cognitive abilities throughout the day appeared to show a greater effect than the sleep-loss and exercise effects over 2 days.