Prefrontal-parietal correlation during performance of the towers of Hanoi task in male children, adolescents and young adults

Effects of comorbidity on executive functions among children with ADHD, finding trends

There is still no basic overview about the effect of various types of comorbidity in executive functions due to two main reasons: (1) the type and number of comorbidities in ADHD is significantly varied, (2) EFs are very diverse and have different neuropsychological properties. Our objective was to determine the effect of comorbid disorders (number and type) on the performance in a wide range (seven) of executive functions in a sample of children with ADHD. Fifty-five male children aged seven to nine years with ADHD were divided into six groups: G1 = ADHD only (ADHD-O), G1 = Oppositional defiant disorder (ODD), G3 = (anxiety/depressive disorder (ADD), G4 = ODD + ADD, G5 = ODD + learning disorder (LD), G6 = ODD + LD + conduct disorder (CD). The six groups exhibited different number of deficits in EFs; G1 showed only 1 deficit in contrast, G6 presented 11. Statistical analysis (ANOVA and logistic regression) identified three most affected EFs: Working memory, generation/classification of semantic categories, and inhibitory control. Alterations in EFs increased mainly in relation to the increase of the specific number and type of comorbidity. To date, no studies have addressed comorbidity from this perspective. A wide range approach of EF confirms the need to further study comorbidity in ADHD from a wide range/variety perspective and determine all possible combinations (number/type) to clarify its contribution to the complex neuropsychology functioning in ADHD.

EEG coherence before and after giving birth

During pregnancy and the postpartum period, changes in brain volume and in motivational, sensory, cognitive, and emotional processes have been described. However, to date, longitudinal modifications of brain function have been understudied. To explore regional cortical coupling, in pregnancy and at 3 months postpartum, we analyzed resting-state electroencephalographic (EEG) coherence in the delta, theta, alpha1, alpha2, beta1, and beta2 frequency bands across frontal and parietal regions of the maternal brain (Fp1, Fp2, F3, F4, P3, and P4). We found that from pregnancy to the postpartum period, mothers showed less intrahemispheric EEG coherence between the frontal and parietal regions in the alpha1 and alpha2 bands, as well as greater interhemispheric EEG coherence between frontopolar regions in the beta2 band. These changes suggest decreased inhibition of neural circuits. These neurophysiological changes may represent an adaptive process characteristic of motherhood.

Brain Activity Associated with the Planning Process during the Long-Time Learning of the Tower of Hanoi (ToH) Task: A Pilot Study

Planning and decision-making are critical managerial functions involving the brain's executive functions. However, little is known about the effect of cerebral activity during long-time learning while planning and decision-making. This study investigated the impact of planning and decision-making processes in long-time learning, focusing on a cerebral activity before and after learning. The methodology of this study involves the Tower of Hanoi (ToH) to investigate executive functions related to the learning process. Generally, ToH is used to measure baseline performance, learning rate, offline learning (following overnight retention), and transfer. However, this study performs experiments on long-time learning effects for ToH solving. The participants were involved in learning the task over seven weeks. Learning progress was evaluated based on improvement in performance and correlations with the learning curve. All participants showed a significant improvement in planning and decision-making over seven weeks of time duration. Brain activation results from fMRI showed a statistically significant decrease in the activation degree in the dorsolateral prefrontal cortex, parietal lobe, inferior frontal gyrus, and premotor cortex between before and after learning. Our pilot study showed that updating information and shifting issue rules were found in the frontal lobe. Through monitoring performance, we can describe the effect of long-time learning initiated at the frontal lobe and then convert it to a task execution function by analyzing the frontal lobe maps. This process can be observed by comparing the learning curve and the fMRI maps. It was also clear that the degree of activation tends to decrease with the number of tasks, such as through the mid-phase and the end-phase of training. The elucidation of this structure is closely related to decision-making in human behavior, where brain dynamics differ between "thinking and behavior" during complex thinking in the early stages of training and instantaneous "thinking and behavior" after sufficient training. Since this is related to human learning, elucidating these mechanisms will allow the construction of a brain function map model that can be used universally for all training tasks.

Prenatal drug exposure and executive function in early adolescence

PURPOSE

Study of the relationship between prenatal cocaine exposure (PCE) and executive function (EF) has yielded inconsistent results. The purpose of the current study is to examine whether PCE, biological sex, environmental risk, and their interaction predicted EF in early adolescence.

METHODS

135 12-year-old adolescents (40.7% with PCE), who were followed prospectively from birth, attempted up to 8 Tower of Hanoi (ToH) puzzle trials of increasing complexity. The number of correctly completed puzzles served as the main outcome measure. Survival analysis was used to examine predictors of the number of successfully completed trials.

RESULTS

As trial difficulty increased, fewer adolescents were able to solve the TOH puzzle. Adolescents from high risk environments and with either prenatal alcohol or prenatal cannabis exposure completed fewer puzzles (p < .05). In addition, a hypothesized 3-way interaction of PCE x sex x environmental risk was found such that cocaine-exposed males with high environmental risk had the worst performance (p < .01).

CONCLUSIONS

The current findings are consistent with prior research indicating that males with PCE may be at particular risk of poorer functioning and highlight the potential importance of examining adolescent's sex and environmental risk as moderators of PCE effects.

Analysis of longitudinal censored semicontinuous data with application to the study of executive dysfunction: The Towers Task

Executive dysfunction is a deficiency in skills of planning and problem solving that characterizes many neuropsychiatric disorders. The Towers Task is a commonly used measure of planning and problem solving for assessing executive function. Towers Task data are usually zero-inflated and right-censored, and ignoring these features can result in biased inference for the disease characterization of executive dysfunction. In this manuscript, a mixed-effects model for longitudinal censored semicontinuous data is developed for analyzing longitudinal Towers Task data from the PREDICT-HD study. The model is contrasted with current practice, and implications for general use are discussed.

Effect of Sexual Arousal on Cortical Coupling During Performance of the Tower of Hanoi Task in Young Men

Sexual arousal affects cognitive processing, which depends on the coordinated functioning among cortical areas. The aim of this research was to determine whether previous observation of videos with sexual content affects the degree of cortical electroencephalographic (EEG) coupling during performance of an executive task. Cortical EEG correlations were calculated in three groups of heterosexual men under three conditions: at rest; during observation of a video with neutral, aggressive, or erotic content; and while performing the Tower of Hanoi task (TOH). Based on self-reports, it was shown that the erotic video induced general and sexual arousal, while the aggressive video affected valence and general arousal. Task performance was similar in all three groups. During performance of TOH, only the erotic group showed a decreased correlation between prefrontal areas with an increased correlation between parietal and prefrontotemporal areas, specifically in the slow bands. It is likely that these changes in the degree of cortical coupling could be associated with the cognitive strategies or functional adaptations that participants require to adequately solve the task during a state of sexual arousal. These data could contribute to improving our understanding of the central nervous mechanisms that underlie the effect of sexual arousal on the cognitive processes involved in tasks like TOH.

Performance of the Towers of Hanoi task and cortical electroencephalographic power changes associated with infancy, adolescence, and early adulthood

The executive functions, which depend on the adequate maturation and functioning of the prefrontal cortex and its connection to posterior zones, follow a process of development as age increases. This work studied changes in the absolute power (AP) of EEG activity recorded in the prefrontal and parietal areas during the performance of the Tower of Hanoi task in children, adolescents, and young adults. Three groups of healthy male subjects such as G1, 11-13; G2, 18-20; and G3, 26-30, years of age were recorded at the F3, F4, P3, and P4 derivations under two conditions: basal and performance of the Towers of Hanoi task. The majority of subjects in G1 failed to complete the task in the allotted time (7 min), while those in G2 and G3 were able to resolve the task quickly and efficiently. During the Towers of Hanoi task, G1 showed an increase of AP in the delta band only in the frontal areas, with a decrease in the alpha1 and alpha2 sub-bands only at the parietal derivations, while G2 and G3 were characterized by an increase of AP in the delta band and a decreased AP in the alpha1 and alpha2 sub-bands in all derivations. These data demonstrate that during the performance of the Towers of Hanoi task, the prefrontal and parietal areas show a characteristic EEG pattern in relation to age. It is probable that the AP patterns obtained in G2 and G3 are associated with the functional changes at cortical levels that adolescents and early adults require to achieve an adequate and fast performance of the Towers of Hanoi task.

Young children selectively seek help when solving problems

There is strong evidence that children show selectivity in their reliance on others as sources of information, but the findings to date have largely been limited to contexts that involve factual information. The current experiments were designed to determine whether children might also show selectivity in their choice of sources within a problem-solving context. Children in two age groups (20-24 months and 30-36 months, total N=60) were presented with a series of conceptually difficult problem-solving tasks and were given an opportunity to interact with adult experimenters who were depicted as either good helpers or bad helpers. Participants in both age groups preferred to seek help from the good helpers. The findings suggest that even young children evaluate others with reference to their potential to provide help and use this information to guide their behavioral choices.