Enduring cognitive dysfunction in unipolar major depression: A test–retest study using the Stroop paradigm

Hammar, Å., Sørensen, L., Årdal, G., Oedegaard, K.J., Kroken, R., Roness, A. & Lund, A. (2009). Enduring cognitive dysfunction in unipolar major depression: A test–retest study using the Stroop‐paradigm. Scandinavian Journal of Psychology. The aim of the study was to investigate automatic and effortful information processing with the Stroop paradigm in a long term perspective in patients with major depressive disorder (MDD). Patients were tested at two test occasions: at inclusion with a Hamilton Depression Rating Scale (HDRS) score >18, and after 6 months, when most patients had experienced symptom reduction. The Stroop paradigm is considered to measure aspects of attention and executive functioning and consists of three conditions/cards: naming the color of the patches (Color), reading of the color‐words (Word) and naming the ink color of color‐words (Color‐Word). The Color‐Word condition is proved to be the most cognitive demanding task and requires the proband to actively suppress interference and is therefore considered to require more effortful information processing, whereas naming the color of the patches and reading the color‐words are expected to be more automatic and less cognitive demanding. A homogenous group of 19 patients with unipolar recurrent MDD according to DSM‐IV and a HDRS score of >18 were included in the study. A control group was individually matched for age, gender and level of education. Depressed patients performed equal to the control group on the Color and Word cards at both test occasions. However, the patients were impaired compared with the control group on the Color‐Word card task at both test occasions. Thus, the depressed patients showed no improvement of effortful attention/executive performance as a function of symptom reduction. The results indicate that the depressed patients showed impaired cognitive performance on cognitive demanding tasks when symptomatic and that this impairment prevailed after 6 months, despite significant improvement in their depressive symptoms.     

Do smokers devaluate smoking cues after go/no-go training?

Objective: Smoking is one of the leading public health problems worldwide. The inability to quit smoking may be the result of the amplified value of smoking-related cues and inhibitory control deficits. Previous research has shown that pairing substance-related cues with no-go trials in go/no-go training reduces the value of these cues, an effect known as devaluation. The current experiment investigated the devaluation effect of go/no-go training on smoking-related cues, and compared this effect between smokers and nonsmokers.

Design and Main Outcome Measures: 39 smokers and 43 nonsmokers were trained to respond immediately to neutral stimuli, but inhibit their reaction when smoking stimuli were presented. Before and after training, participants evaluated smoking and neutral stimuli, where part of these stimuli were subsequently presented in the training, and the other part was not used in training.

Results: Not responding to smoking stimuli in go/no-go training decreased subsequent evaluations of trained smoking stimuli compared to untrained smoking stimuli, thereby replicating food and alcohol studies and extending the devaluation effect to smoking-related cues. This devaluation effect was found for both smokers and non-smokers.

Conclusion: Smoking-related cues can be devaluated in smokers and non-smokers, thereby showing the potential for Go/No-Go training in smoking cessation interventions.     

Executive functions in kindergarteners with high levels of disruptive behaviours

Executive function (EF) deficits have yet to be demonstrated convincingly in children with disruptive behaviour disorders (DBD), as only a few studies have reported these. The presence of EF weaknesses in children with DBD has often been contested on account of the high comorbidity between DBD and attention‐deficit/hyperactivity disorder (ADHD) and of methodological shortcomings regarding EF measures. Against this background, the link between EF and disruptive behaviours in kindergarteners was investigated using a carefully selected battery of EF measures. Three groups of kindergarteners were compared: (1) a group combining high levels of disruptive behaviours and ADHD symptoms (COMB); (2) a group presenting high levels of disruptive/aggressive behaviours and low levels of ADHD symptoms (AGG); and (3) a normative group (NOR). Children in the COMB and AGG groups presented weaker inhibition capacities compared with normative peers. Also, only the COMB group showed weaker working memory capacities compared with the NOR group. Results support the idea that preschool children with DBD have weaker inhibition capacities and that this weakness could be common to both ADHD and DBD.     

Pubertal status associations with reward and threat sensitivities and subcortical brain volumes during adolescence

Adolescence is characterized by complex developmental processes that impact behavior, biology, and social functioning. Two such adolescence-specific processes are puberty and increases in reward sensitivity. Relations between these processes are poorly understood. The present study focused on examining unique effects of puberty, age, and sex on reward and threat sensitivities and volumes of subcortical brain structures relevant for reward/threat processing in a healthy sample of 9–18 year-olds. Unlike age, pubertal status had a significant unique positive relationship with reward sensitivity. In addition, there was a trend for adolescent females to exhibit higher threat sensitivity with more advanced pubertal development and higher reward and threat sensitivity with older age. Similarly, there were significant puberty by sex interaction effects on striatal volumes, i.e., left nucleus accumbens and right pallidum. The present pattern of results suggests that pubertal development, independent of chronological age, is uniquely associated with reward hypersensitivity and with structural differences in striatal regions implicated in reward processing.     

Individuality of movements in music – Finger and body movements during playing of the flute

The achievement of mastery in playing a composition by means of a musical instrument typically requires numerous repetitions and corrections according to the keys and notations of the music piece. Nevertheless, differences in the interpretation of the same music piece by highly skilled musicians seem to be recognizable. The present study investigated differences within and between skilled flute players in their finger and body movements playing the same piece several times on the same and on different days. Six semiprofessional and four professional musicians played an excerpt of Mozart’s Flute Concerto No. 2 several times on three different days. Finger and body movements were recorded by 3D motion capture and analyzed by linear and nonlinear classification approaches. The findings showed that the discrete and continuous movement timing data correctly identified individuals up to 100% by means of their finger movements and up to 94% by means of their body movements. These robust examples of identifying individual movement patterns contradict the prevailing models of small, economic finger movements that are favored in the didactic literature for woodwind players and question traditional recommendations for teaching the learning of motor skills.     

The nature of inhibition in a working memory search task

Inhibition is one of the key processes that regulate working memory (WM) activity. The main research question concerned the nature of inhibition of highlighted information in WM. The study was designed to examine two competing hypotheses. The first assumed that inhibition is carried out by deletion of irrelevant information from the focus of attention (cognitive inhibition account). An alternative hypothesis assumed that it is the response to a correctly recognised stimulus that is inhibited (effortful response inhibition account). Two experiments with a spatial modification of the WM serial search task were conducted wherein two factors were manipulated: serial order of the items, and distance from the central fixation point. In both experiments, higher response time was correlated with a smaller distance from the fixation point. The inhibited items were recognised equally efficiently or better than the uninhibited items. The results support the effortful response inhibition account over the cognitive inhibition account.     

Proactive inhibitory control: A general biasing account

Flexible behavior requires a control system that can inhibit actions in response to changes in the environment. Recent studies suggest that people proactively adjust response parameters in anticipation of a stop signal. In three experiments, we tested the hypothesis that proactive inhibitory control involves adjusting both attentional and response settings, and we explored the relationship with other forms of proactive and anticipatory control. Subjects responded to the color of a stimulus. On some trials, an extra signal occurred. The response to this signal depended on the task context subjects were in: in the ‘ignore’ context, they ignored it; in the ‘stop’ context, they had to withhold their response; and in the ‘double-response’ context, they had to execute a secondary response. An analysis of event-related brain potentials for no-signal trials in the stop context revealed that proactive inhibitory control works by biasing the settings of lower-level systems that are involved in stimulus detection, action selection, and action execution. Furthermore, subjects made similar adjustments in the double-response and stop-signal contexts, indicating an overlap between various forms of proactive action control. The results of Experiment 1 also suggest an overlap between proactive inhibitory control and preparatory control in task-switching studies: both require reconfiguration of task-set parameters to bias or alter subordinate processes. We conclude that much of the top-down control in response inhibition tasks takes place before the inhibition signal is presented.     

Inhibition Tasks Are Not Associated with a Variety of Behaviours in College Students

Executive functions are (EF) top-down control processes involved in regulating thoughts, ignoring distractions, and inhibiting impulses. It is widely believed that these processes are critical to self-control and, therefore, that performance on behavioural task measures of EF should be associated with individual differences in everyday life outcomes. The purpose of the present study was to test this assumption, focusing on the core executive function facet of inhibition. A sample of 463 undergraduates completed five laboratory inhibition tasks, along with three self-report measures of self-control and 28 self-report measures of life outcomes. Results showed that although most of the life outcome measures were associated with self-reported self-control, only one of the outcomes was associated with inhibition task performance at the latent-variable level, and this association was in the unexpected direction. Furthermore, few associations were found at the individual task level. These findings challenge the criterion validity of lab-based inhibition tasks. More generally, when considered alongside the known lack of convergent validity between inhibition tasks and self-report measures of self-control, the findings cast doubt on the task's construct validity as measures of self-control processes. Potential methodological and theoretical reasons for the poor performance of laboratory-based inhibition tasks are discussed. © 2020 European Association of Personality Psychology     

Orienting to guilty knowledge

The Guilty Knowledge Test (GKT; Lykken, 1959) assesses whether suspects conceal information about a crime ( “guilty knowledge”). Previous studies have demonstrated larger physiological reactions to guilty knowledge compared to unknown information. In three experiments, we investigated whether guilty knowledge also demands attention. During an alleged polygraph examination, participants were presented with to‐be‐detected pictures ( “guilty knowledge”), nonsignificant, familiar pictures ( “mere knowledge”), and previously unseen pictures ( “neutral information”) for 250 ms in a modified dot probe task. In all three experiments, probe responses were slower on guilty knowledge trials as compared to the neutral trials. Results are discussed in terms of an information‐processing view on orienting to guilty knowledge.