Efficacy of guided self-help behavioural activation and physical activity for depression: a randomized controlled trial

Behavioural activation and physical activity have received empirical support that highlight their efficacy in reducing depression. Even though both behavioural activation and physical activity share the common goal of reactivating the individual, limited research has directly compared these interventions, and more research is required to evaluate their efficacy when offered in low-intensity formats. The present study involves a randomized controlled clinical trial comparing the efficacy of two guided self-help interventions for the treatment of depression: behavioural activation and physical activity. Fifty-nine participants presenting mild-to-moderate symptoms of depression were randomized either to a behavioural activation intervention (n = 20), a physical activity intervention (n = 19) or a wait-list control group (n = 20). All participants completed symptom measure pre-, mid- and post-intervention, as well as at a two-month follow-up. Mixed-model analyses of variance revealed that both interventions were significantly more efficacious in reducing depressive symptoms in comparison with the control group. Physical activity involved significantly less time-investment compared to the behavioural activation condition (less than half the amount of time). These results indicate that physical activity and behavioural activation both effectively reduce depressive symptoms and are favourably applicable in low-intensity formats. Implications of these results and avenues for future research are discussed.     

Interoception and gender: What aspects should we pay attention to?

Interoception is involved in both somatic and mental disorders with different prevalence between genders; however, gender differences are often neglected. To examine the potential gender differences in interoceptive awareness, we recruited 376 healthy subjects (51% males, aged 17–30 years), to fill in the Multidimensional Assessment of Interoceptive Awareness (MAIA). Of that sample, in a subgroup of 40 subjects (50% males), interoceptive accuracy was assessed by heartbeat counting task (HCT).The results on interroceptive awareness suggest that females tend to notice bodily sensations more often, better understand relations between bodily sensations and emotional states, worry or experience more emotional distress with sensations of pain or discomfort and see body as less safe. The results of interoceptive accuracy further suggest that females are less efficient in consciously detecting heartbeats. Therefore, gender should be considered when interoceptive evaluation is performed in disorders associated to bodily sensations and to the emotional/mood states.     

Speed behaviour as a choice between observing and exceeding the speed limit

Despite speed behaviour being defined as a choice between several possible speeds, studies using theory of reasoned action or theory of planned behaviour to predict and understand speed behaviour have focused on exceeding and not on observing the speed limit. This study examines whether the evaluation of exceeding but also of observing the speed limit contributes to improving predictions of self-reported speed behaviour and determining intentions to produce each of these two behavioural options. For a specific driving situation (straight road with 90 km/h speed limit), 238 young male drivers reported the speed at which they would drive at and where asked to assess the theory of planned behaviour key constructs with respect to observing and exceeding the speed limit by at least 20 km/h. Results showed that the amount of explained variance of self-reported speed behaviour, as well as intentions to observe and to exceed the speed limit by at least 20 km/h, increased significantly when the evaluations of the two options were introduced in the same stepwise regression analysis. Theoretical and practical implications of the results are discussed.     

Human walk-to-run transition in the context of the behaviour of complex systems

This study had two main aims: 1) to investigate if the walk-to-run (WR-) transition occurs when the speed of locomotion is kept constant below the WR-transition speed (speed clamp) and the stride rate is increased monotonously using a metronome and 2) to investigate if diversion of attention and awareness from the locomotion process influences the position of the WR-transition in stride rate, stride length, and locomotion speed (SrSlLs) space.Eighteen healthy individuals (13 men and 5 women) were recruited (age: 23.9 ± 1.5 years, height: 1.77 ± 0.10 m and body mass: 77.3 ± 12.8 kg). Stride-by-stride stride rates, stride lengths, locomotion speeds, and duty factors were determined on a treadmill in 4 different tests: 1) reference WR-transition, 2) preferred walking speed, 3) dual-task test including arithmetic calculations and 4) four speed clamp bouts with different initial velocities.Walk-to-run transitions were elicited in all participants in the speed clamp bouts. When the stride rate ramp was clamped at preferred walking speed the WR-transition stride rate was not significantly different from the WR-transition stride rate during the reference test (t = 2.2, p = 0.312). However, in the SrSlLs space the speed clamp WR-transitions all deviated from the position of the reference WR-transition. Additionally, it was demonstrated that intensive attentional diversion using a dual-task paradigm had very little influence on the position of the WR-transition in the SrSlLs space.It is argued that these observations can be explained in the context of the behavior of complex systems.     

Spatial learning in pigs: effects of environmental enrichment and individual characteristics on behaviour and performance

This study investigated the effects of both environmental enrichment and individual behavioural characteristics on spatial cognitive capabilities of pigs, using a novel latent spatial learning paradigm based on Tolman’s detour experiments (1948). Pigs were housed either in ‘barren’ pens or in pens enriched with straw bedding from birth. Pigs were restrained in a Backtest at 10 and 17 days postpartum. Based on their escape behaviour in this test, which has been shown to reflect their behavioural style, six ‘high-resisting’(HR) and six ‘low-resisting’ (LR) pigs were selected from each housing environment (n = 24 in total). At 12 weeks of age, pairs of pen mates (LR and HR) were exposed to a maze three times (exploration trials). Pigs were then placed individually in the maze, and social reinstatement proved to be a strong incentive to find the exit leading to the home pen. We subsequently blocked the direct route to the exit, forcing animals to find a detour (memory test 1, MT1). This test was repeated once to investigate the relative improvement, i.e. detour learning (memory test 2, MT2). Housing condition and Backtest response strongly affected exploration patterns. In spite of this, no effects on performance during the subsequent memory tests were found. Performance was substantially improved in MT2, indicating that once a goal is apparent, pigs are able to solve a complex spatial memory task easily. In conclusion, social reinstatement provided a good incentive to complete a spatial task, and the substantial improvement in performance between MT1 and MT2 stresses the need for task complexity when testing spatial memory in pigs. Housing conditions or individual behavioural style did not affect spatial memory during MT1 or MT2. However, housing environment and behavioural style strongly affected explorative behaviour of pigs in an unfamiliar maze during both exploration trials and memory tests. This implicates that apparent effects of environmental enrichment on spatial learning and memory in pigs might reflect differences in explorative patterns rather than in cognitive processes.     

Emotional reactivity and self-regulation in relation to personality disorders

Associations of both reactive and regulative temperamental features with personality disorders (PDs) are investigated in a sample of 162 normal controls and 89 psychiatric inpatients. Reactive and regulative temperamental features were assessed by means of the BIS/BAS Scales and the Attentional Control Scale. Dimensional PD scores were obtained by using the ADP-IV. All PDs were characterized by low levels of effortful control, cluster C PDs by high BIS and cluster B PDs by high BAS. For several PDs, BIS and effortful control interacted: BIS was only related to severe PD pathology if effortful control was low. Clinical implications of these findings are discussed.     

Phallometric diagnosis with 'nonadmitters'

The phallometric method of assessing erotic value of presented stimuli has two main tasks, one is in the breaking down of complex (potentially) sexual stimuli into components, the other is in diagnosing anomalous erotic preferences in ‘Nonadmitters’, i.e. in persons whose behaviour would imply there is such an anomaly, but who deny its presence. Differentiation between Admitters and Nonadmitters was attained by two verbal Admitter scales. Comparison of the scores on these scales with results of phallometric assessment showed (by mutual validation) that the phallometric method diagnoses Admitters more accurately than Nonadmitters. After that, the validity was tested of a new mode of the phallometric method, designed for diagnosing pedo- or hebephilia in Nonadmitters. In cases of homosexual pedophilia or hebephilia (but not in the heterosexual cases) the new Nonadmitter mode was superior to the Standard procedure.     

Behavioural adaptation to driving with an adaptive cruise control (ACC)

The present paper describes a study that aims at assessment of driver behaviour in response to new technology, particularly Adaptive Cruise Control Systems (ACCs), as a function of driving style. In this study possible benefits and drawbacks of Adaptive Cruise Control Systems (ACCs) were assessed by having participants drive in a simulator. The four groups of participants taking part differed on reported driving styles concerning Speed (driving fast) and Focus (the ability to ignore distractions), and drove in ways which were consistent with these opinions. The results show behavioural adaptation with an ACC in terms of higher speed, smaller minimum time headway and larger brake force. Driving style group made little difference to these behavioural adaptations. Most drivers evaluated the ACC system very positively, but the undesirable behavioural adaptations observed should encourage caution about the potential safety of such systems.     

Throwing light on the dark side of personality: Reinforcement sensitivity theory and primary/secondary psychopathy in a student population

In a student sample, we examined two major issues in relation to primary/secondary subtypes of psychopathy and the reinforcement sensitivity theory of personality: the roles played by (a) fear (related to the fight-flight-freeze system, FFFS) and anxiety (related to the behavioural inhibition system, BIS), and (b) different aspects of the behavioural approach system (BAS). Largely consistent with Corr’s (2010a) proposal concerning the neuropsychological deficits associated with the psychoticism-psychopathy continuum, results confirmed that low BIS activity was associated with both primary and secondary psychopathy; whereas low FFFS activity was associated with only primary psychopathy. In relation to the BAS, reward sensitivity and drive were positively related to primary psychopathy; whereas Fun Seeking was negatively related to primary psychopathy but positively related to secondary psychopathy. These results represent a more nuanced picture of FFFS/BIS/BAS and dispositional psychopathy in a student sample. Specifically, they challenge the view that low BIS is preferentially associated with primary psychopathy and a high BAS is preferentially associated with secondary psychopathy. Further work is needed to confirm that these findings extend to clinical and forensic psychopathy populations.