Bases neurales de la toma de decisiones

Neural underpinnings of ethical decisions in life and death dilemmas in naïve and expert firefighters

When a single choice impacts on life outcomes, faculties to make ethical judgments come into play. Here we studied decisions in a real-life setting involving life-and-death outcomes that affect others and the decision-maker as well. We chose a genuine situation where prior training and expertise play a role: firefighting in life-threatening situations. By studying the neural correlates of dilemmas involving life-saving decisions, using realistic firefighting situations, allowed us to go beyond previously used hypothetical dilemmas, while addressing the role of expertise and the use of coping strategies (n = 47). We asked the question whether the neural underpinnings of deontologically based decisions are affected by expertise. These realistic life-saving dilemmas activate the same core reward and affective processing network, in particular the ventromedial prefrontal cortex, nucleus accumbens and amygdala, irrespective of prior expertise, thereby supporting general domain theories of ethical decision-making. We found that brain activity in the hippocampus and insula parametrically increased as the risk increased. Connectivity analysis showed a larger directed influence of the insula on circuits related to action selection in non-experts, which were slower than experts in non rescuing decisions. Relative neural activity related to the decision to rescue or not, in the caudate nucleus, insula and anterior cingulate cortex was negatively associated with coping strategies, in experts (firefighters) suggesting practice-based learning. This shows an association between activity and expert-related usage of coping strategies. Expertise enables salience network activation as a function of behavioural coping dimensions, with a distinct connectivity profile when facing life-rescuing dilemmas.

Perturbations in risk/reward decision making and frontal cortical catecholamine regulation induced by mild traumatic brain injury

Mild traumatic brain injury (mTBI) disrupts cognitive processes that influence risk taking behavior. Little is known regarding the effects of repetitive mild injury (rmTBI) or whether these outcomes are sex specific. Risk/reward decision making is mediated by the prefrontal cortex (PFC), which is densely innervated by catecholaminergic fibers. Aberrant PFC catecholamine activity has been documented following TBI and may underlie TBI-induced risky behavior. The present study characterized the effects of rmTBI on risk/reward decision making behavior and catecholamine transmitter regulatory proteins within the PFC. Rats were exposed to sham, single (smTBI), or three closed-head controlled cortical impact (CH-CCI) injuries and assessed for injury-induced effects on risk/reward decision making using a probabilistic discounting task (PDT). In the first week post-final surgery, mTBI increased risky choice preference. By the fourth week, males exhibited increased latencies to make risky choices following rmTBI, demonstrating a delayed effect on processing speed. When levels of tyrosine hydroxylase (TH) and the norepinephrine reuptake transporter (NET) were measured within subregions of the PFC, females exhibited dramatic increases of TH levels within the orbitofrontal cortex (OFC) following smTBI. However, both males and females demonstrated reduced levels of OFC NET following rmTBI. These results indicate the OFC is susceptible to catecholamine instability after rmTBI and suggests that not all areas of the PFC contribute equally to TBI-induced imbalances. Overall, the CH-CCI model of rmTBI has revealed time-dependent and sex-specific changes in risk/reward decision making and catecholamine regulation following repetitive mild head injuries.

Differences in brain connectivity of meditators during assessing neurocognition via gamified experimental logic task: A machine learning approach

Meditation practices increase attention, memory, and self-awareness. The neuroscientific study of meditation has helped gain useful insights into the functional changes in the brain. In this study, we have assessed the performance of meditators with different years of practice while performing an engaging task rather than studying the meditation practice itself. This task helps assess many neural processes simultaneously and represents task performance in presence of multiple audio-visual distractors as in a real-life scenario. The long-term practice of meditation could bring neuroplastic changes in the way cognitive processing is carried out. It could be conscious and effortful in short-term practitioners and relatively unconscious and effortless in long-term practitioners. Our goal is to understand if it is possible to differentiate between long-term and short-term meditators solely based on their cognitive processing. A group of proficient Rajayoga meditators from the Brahma Kumaris were recruited based on their meditation experience-Long-Term Practitioners (n = 12, mean 13,596 h) and Short-Term Practitioners (n = 10, mean 1095 h). A task-based functional Magnetic Resonance Imaging was acquired while the subjects performed the task. Functional Connectivity Analysis was performed to derive the correlation measures to be used as features for classification. Five supervised Machine Learning algorithms Logistic Regression, Support Vector Machine, Decision Tree, Random Forest, and Gradient Boosted Tree were used for classification. Among all the classifiers Gradient Boosted Tree performed the best with an accuracy of 77% when all the four Functional Connectivity Metrics were used. Connectivity in visual areas, cerebellum, left rostral prefrontal cortex, and middle frontal gyrus was found to be higher in long-term meditators. Such a classification demonstrates that long-term meditation practice brings about neuroplastic changes that influence cognitive processing.

Cortical functionality during reversal learning on a decision-making task in young men

The evaluation of external and internal stimuli permits the ongoing actualization of choice-related information and, thus, the association between stimuli and outcomes. This process is essential to decision-making as it allows constant adaptation to environmental changes in order to maximize gains and minimize losses. Reversal learning paradigms are used to study this process, which has been associated with prefrontal cortex activity (frontopolar, dorsolateral) in conjunction with posterior areas (parietal, temporal), due to their participation in integrating and processing the stimuli-reward relation. The aim of this study was to assess the cortical functionality associated with reversal learning during the decision-making process. The EEG activity of 22 young men was recorded while performing a decision-making task in a reversal learning condition compared to an initial learning condition. EEG data were analyzed during evaluation of the stimuli, before motor execution (formation of preferences), and during task feedback (outcome evaluation). The formation of preferences stage was characterized by a higher correlation of the alpha2 band between the parietal cortices. In the feedback stage of the reversal learning condition, a higher absolute power of the theta band in the left dorsolateral (F3), and a lower correlation of the alpha1 band between the right frontopolar and dorsolateral (Fp2-F4), as well as between the right frontopolar and temporal (Fp2-T4), were observed. The data obtained show that the EEG activity of the areas recorded changed in the evaluation of the stimuli information in the reversal learning condition during a decision-making task.

Decision Making: a Theoretical Review

Decision-making is a crucial skill that has a central role in everyday life and is necessary for adaptation to the environment and autonomy. It is the ability to choose between two or more options, and it has been studied through several theoretical approaches and by different disciplines. In this overview article, we contend a theoretical review regarding most theorizing and research on decision-making. Specifically, we focused on different levels of analyses, including different theoretical approaches and neuropsychological aspects. Moreover, common methodological measures adopted to study decision-making were reported. This theoretical review emphasizes multiple levels of analysis and aims to summarize evidence regarding this fundamental human process. Although several aspects of the field are reported, more features of decision-making process remain uncertain and need to be clarified. Further experimental studies are necessary for understanding this process better and for integrating and refining the existing theories.

The Monash Autism-ADHD genetics and neurodevelopment (MAGNET) project design and methodologies: a dimensional approach to understanding neurobiological and genetic aetiology

Background

ASD and ADHD are prevalent neurodevelopmental disorders that frequently co-occur and have strong evidence for a degree of shared genetic aetiology. Behavioural and neurocognitive heterogeneity in ASD and ADHD has hampered attempts to map the underlying genetics and neurobiology, predict intervention response, and improve diagnostic accuracy. Moving away from categorical conceptualisations of psychopathology to a dimensional approach is anticipated to facilitate discovery of data-driven clusters and enhance our understanding of the neurobiological and genetic aetiology of these conditions. The Monash Autism-ADHD genetics and neurodevelopment (MAGNET) project is one of the first large-scale, family-based studies to take a truly transdiagnostic approach to ASD and ADHD. Using a comprehensive phenotyping protocol capturing dimensional traits central to ASD and ADHD, the MAGNET project aims to identify data-driven clusters across ADHD-ASD spectra using deep phenotyping of symptoms and behaviours; investigate the degree of familiality for different dimensional ASD-ADHD phenotypes and clusters; and map the neurocognitive, brain imaging, and genetic correlates of these data-driven symptom-based clusters.

Methods

The MAGNET project will recruit 1,200 families with children who are either typically developing, or who display elevated ASD, ADHD, or ASD-ADHD traits, in addition to affected and unaffected biological siblings of probands, and parents. All children will be comprehensively phenotyped for behavioural symptoms, comorbidities, neurocognitive and neuroimaging traits and genetics.

Conclusion

The MAGNET project will be the first large-scale family study to take a transdiagnostic approach to ASD-ADHD, utilising deep phenotyping across behavioural, neurocognitive, brain imaging and genetic measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13229-021-00457-3.

Abnormal negative feedback processing in individuals with autistic traits in the Iowa gambling task: Evidence from behavior and event-related potentials

Value-based decision making plays an important role in social interaction. Previous studies have reported that individuals with autism spectrum disorder (ASD) exhibit deficits in terms of decision making. However, it is still unknown clearly whether individuals with high autistic traits within nonclinical populations employ abnormal neural substrates in value-based decision-making. To explore this issue, we investigated value-based decision making and its neural substrates in individuals with high and low autistic traits within a typically developing population who completed the revised Iowa gambling task (IGT) based on measurements of event-related potentials (ERPs). The IGT net scores were significantly lower in the group with high autistic traits than the group with low autistic traits in the fifth and sixth blocks. The ERP results showed that the feedback-related negativity (FRN) amplitude in individuals with high autistic traits allowed slight discrimination between positive and negative feedback in the low-risk option. The event-related spectral perturbations (ERSPs) and inter-trial coherence (ITC) of the theta-band frequency were also lower in the group with high autistic traits than the group with low autistic traits in the loss low-risk option. The results obtained in this study indicate that individuals with high autistic traits exhibit an unusual negative feedback process and relevant neural substrate. The FRN amplitude and theta-band oscillation may comprise a neural index of abnormal decision-making processes in individuals with high autistic traits. This study of a small sample may be considered an important step toward a more comprehensive understanding of the autism "spectrum" within a nonclinical population based on cognitive neuroscience.

Association of TDP-43 Pathology With Domain-specific Literacy in Older Persons

BACKGROUND

Low health and financial literacy may be an early behavioral manifestation of cognitive impairment, dementia, and accumulating Alzheimer pathology. However, there are limited studies investigating the behavioral features associated with hyperphosphorylated transactive response DNA-binding protein-43 (TDP-43), a common age-related pathology, and even fewer studies investigating the neurobiological basis underlying low literacy in aging.

OBJECTIVE

To test the hypothesis that TDP-43 pathology is associated with lower literacy.

MATERIALS AND METHODS

Data came from 293 community-based older persons who were enrolled in 2 ongoing studies of aging. Participants completed literacy and cognitive assessments, consented to brain donation, and underwent detailed neuropathologic evaluation for Alzheimer disease (AD) and TDP-43. Linear regression models assessed the association of TDP-43 with literacy after adjusting for demographics, and AD pathology. Posthoc pairwise comparisons examined whether the level of literacy differed by TDP-43 stage.

RESULTS

TDP-43 pathology was associated with lower literacy (estimate=-3.16; SE=0.86; P<0.001), above and beyond demographics and AD pathology, and this association persisted even after additionally adjusting for global cognition (estimate=-1.53; SE=0.74; P=0.038). Further, literacy was lower among persons with neocortical TDP-43 pathology compared with those without TDP-43 pathology.

CONCLUSIONS

TDP-43 pathology is associated with lower health and financial literacy in old age, above and beyond AD pathology.

Sexual Behavioral Disinhibition Associated with Nucleus Lentiformis Lesion: A Forensic Neuroscience Perspective Through a Case

Organic brain disturbances particularly related to frontal cortex structures and subcortical areas including the basal ganglia may play a role in behavioral disinhibition disorders. Kluver-Bucy syndrome (KBS), which is one of the better knowns of these syndromes, includes hyperorality, visual agnosia, and hypersexuality, has been reported to occur after temporal lobe and amygdala lesions; however, several patients who had focal lesions in areas other than the temporal cortex and amygdala have been reported to present partial KBS symptoms. Nucleus lentiformis refers to a large portion of the basal ganglia including the putamen and globus pallidus, and specific structures within this broad area are known to be important for reward and value-based decision making. To date, KBS symptoms including hypersexual behavior associated with nucleus lentiformis lesions have never been reported. Here, we present a 38-year-old male patient who developed increased sexual interest and hyperorality after infarctions in the right lenticular nucleus and right occipitotemporal region and committed a first-degree sexual assault. He was sent to our institution for the assessment of criminal responsibility to the index sexual crime. According to a comprehensive and thorough forensic psychiatric evaluation, he was diagnosed as having an organic personality disorder with partial KBS symptoms. To the best of our knowledge, this is the first reported case of deviant sexual behavior and hyperorality developing after nucleus lentiformis infarction. We aimed to discuss possible neurobiologic explanations of late-onset deviant sexual behavior, which resulted in sexual criminal behavior following a cerebrovascular infarction.

Decision-making profile in older adults: the influence of cognitive impairment, premorbid intelligence and depressive symptoms

OBJECTIVE

Decision-making (DM) is a component of executive functioning. DM is essential to make proper decisions regarding important life and health issues. DM can be impaired in cognitive disorders among older adults, but current literature is scarce. The aim of this study was to evaluate the DM profile in participants with and without cognitive impairment.

DESIGN

Cross-sectional analysis of a cohort study on cognitive aging.

PARTICIPANTS

143 older adults.

SETTING

University-based memory clinic.

METHODS

Patients comprised three groups after inclusion and exclusion criteria: healthy controls (n=29), mild cognitive impairment (n=81) and dementia (n=33). Participants were evaluated using an extensive neuropsychological protocol. DM profile was evaluated by the Melbourne Decision Making Questionnaire. Multinomial logistic regression was used to evaluate associations between age, sex, educational level, estimated intelligence quotient (IQ), cognitive disorders, depressive or anxiety symptoms, and the DM profiles.

RESULTS

The most prevalent DM profile was the vigilant type, having a prevalence of 64.3%. The vigilant profile also predominated in all three groups. The multinomial logistic regression showed that the avoidance profile (i.e. buck-passing) was associated with a greater presence of dementia (p=0.046) and depressive symptoms (p=0.024), but with less anxious symptoms (p=0.047). The procrastination profile was also associated with depressive symptoms (p=0.048). Finally, the hypervigilant profile was associated with a lower pre-morbid IQ (p=0.007).

CONCLUSION

Older adults with cognitive impairment tended to make more unfavorable choices and have a more dysfunctional DM profile compared to healthy elders.

Better late than never (or early): Music training in late childhood is associated with enhanced decision-making

Decision-making is critical to everyday life. Here we ask: to what extent does music training benefit decision-making? Supported by strong associations between music training and enhanced cross-domain skills, we hypothesize that musicians may show decision-making advantages relative to non-musicians. Prior work has also argued for a "critical period" for cross-domain plasticity such that beginning music training early enhances sensorimotor brain regions that mature early in life. Given that brain regions supporting decision-making begin maturing late in childhood, we hypothesized that an advantage in decision-making may only be present in musicians who began music training later in childhood. To test this hypothesis, young adults who began music training before and after 8 years of age (early-trained musicians, ET; late-trained musicians, LT, respectively) and non-musicians (NM) performed a decision-making task. We found a decision-making advantage in LT relative to ET and NM. To better understand the mechanism of the LT advantage, we conducted computational modeling on participant responses and found that LT were less biased by recent outcomes and incorporated longer strings of outcomes when deciding among the choice options. These results tentatively suggest that music training may confer decision-making enhancements, and carry strong implications for the utility of music training in childhood.