The neural correlates of problem states: testing FMRI predictions of a computational model of multitasking

Background

It has been shown that people can only maintain one problem state, or intermediate mental representation, at a time. When more than one problem state is required, for example in multitasking, performance decreases considerably. This effect has been explained in terms of a problem state bottleneck.

Methodology

In the current study we use the complimentary methodologies of computational cognitive modeling and neuroimaging to investigate the neural correlates of this problem state bottleneck. In particular, an existing computational cognitive model was used to generate a priori fMRI predictions for a multitasking experiment in which the problem state bottleneck plays a major role. Hemodynamic responses were predicted for five brain regions, corresponding to five cognitive resources in the model. Most importantly, we predicted the intraparietal sulcus to show a strong effect of the problem state manipulations.

Conclusions

Some of the predictions were confirmed by a subsequent fMRI experiment, while others were not matched by the data. The experiment supported the hypothesis that the problem state bottleneck is a plausible cause of the interference in the experiment and that it could be located in the intraparietal sulcus.     

Planning and problem solving: From neuropsychology to functional neuroimaging

This article provides an overview of recent research on human planning and problem solving. As an introduction, these two cognitive domains will be described and discussed from the perspective of experimental and cognitive psychology. The following sections will focus on the role of the prefrontal cortex in planning and problem solving and on disorders of these functions in patients with frontal-lobe lesions. Specific emphasis will be placed on the Tower of London task, a well established and widely used neuropsychological test of planning ability. We will present an overview of recent behavioural and neuroimaging studies that have employed the Tower of London task to draw specific conclusions about the likely neural and cognitive basis of planning function. Finally, we turn to a number of new directions and recent studies exploring different aspects of planning and problem solving and their association to related cognitive dimensions.     

Monitoring Cognitive and Emotional Processes Through Pupil and Cardiac Response During Dynamic Versus Logical Task

The paper deals with the links between physiological measurements and cognitive and emotional functioning. As long as the operator is a key agent in charge of complex systems, the definition of metrics able to predict his performance is a great challenge. The measurement of the physiological state is a very promising way but a very acute comprehension is required; in particular few studies compare autonomous nervous system reactivity according to specific cognitive processes during task performance and task related psychological stress is often ignored. We compared physiological parameters recorded on 24 healthy subjects facing two neuropsychological tasks: a dynamic task that require problem solving in a world that continually evolves over time and a logical task representative of cognitive processes performed by operators facing everyday problem solving. Results showed that the mean pupil diameter change was higher during the dynamic task; conversely, the heart rate was more elevated during the logical task. Finally, the systolic blood pressure seemed to be strongly sensitive to psychological stress. A better taking into account of the precise influence of a given cognitive activity and both workload and related task-induced psychological stress during task performance is a promising way to better monitor operators in complex working situations to detect mental overload or pejorative stress factor of error.     

Insightful problem solving in an Asian elephant

The "aha" moment or the sudden arrival of the solution to a problem is a common human experience. Spontaneous problem solving without evident trial and error behavior in humans and other animals has been referred to as insight. Surprisingly, elephants, thought to be highly intelligent, have failed to exhibit insightful problem solving in previous cognitive studies. We tested whether three Asian elephants (Elephas maximus) would use sticks or other objects to obtain food items placed out-of-reach and overhead. Without prior trial and error behavior, a 7-year-old male Asian elephant showed spontaneous problem solving by moving a large plastic cube, on which he then stood, to acquire the food. In further testing he showed behavioral flexibility, using this technique to reach other items and retrieving the cube from various locations to use as a tool to acquire food. In the cube's absence, he generalized this tool utilization technique to other objects and, when given smaller objects, stacked them in an attempt to reach the food. The elephant's overall behavior was consistent with the definition of insightful problem solving. Previous failures to demonstrate this ability in elephants may have resulted not from a lack of cognitive ability but from the presentation of tasks requiring trunk-held sticks as potential tools, thereby interfering with the trunk's use as a sensory organ to locate the targeted food.     

Regional Gray Matter Density Associated with Cognitive Reflectivity–Impulsivity: Evidence from Voxel-Based Morphometry

When faced with a problem or choice, humans can use two different strategies: “cognitive reflectivity,” which involves slow responses and fewer mistakes, or “cognitive impulsivity,” which comprises of quick responses and more mistakes. Different individuals use these two strategies differently. To our knowledge, no study has directly investigated the brain regions involved in reflectivity–impulsivity; therefore, this study focused on associations between these cognitive strategies and the gray matter structure of several brain regions. In order to accomplish this, we enrolled 776 healthy, right-handed individuals (432 men and 344 women; 20.7 ± 1.8 years) and used voxel-based morphometry with administration of a cognitive reflectivity–impulsivity questionnaire. We found that high cognitive reflectivity was associated with greater regional gray matter density in the ventral medial prefrontal cortex. Our finding suggests that this area plays an important role in defining an individual’s trait associated with reflectivity and impulsivity.     

The computationalist reformulation of the mind-body problem

Computationalism, or digital mechanism, or simply mechanism, is a hypothesis in the cognitive science according to which we can be emulated by a computer without changing our private subjective feeling. We provide a weaker form of that hypothesis, weaker than the one commonly referred to in the (vast) literature and show how to recast the mind-body problem in that setting.     

The role of long-chain polyunsaturated fatty acids in infant cognitive development

Dietary long-chain polyunsaturated fatty acids (LCPUFA) in infancy are necessary for normal brain growth and development, and may play an important role in the development of infant cognition. Several randomized, controlled studies have evaluated the effects of feeding both term and preterm infants formula containing LCPUFA or no LCPUFA on a variety of measures of cognitive behaviour. Studies of the relation of LCPUFA to performance on tests of psychomotor development have produced inconsistent results, with supplemented infants demonstrating either higher scores or no differences in comparison to controls. This pattern suggests that global tests of development may be insufficiently sensitive for detecting the effects of LCPUFA on infant cognitive function. In contrast, studies assessing the influence of LCPUFA on development of specific cognitive behaviours have shown a significant advantage for supplemented infants on measures of visual attention and problem solving. These results suggest that LCPUFA may enhance more efficient information processing or attention regulation in infants. Whether there are any long-term effects of dietary LCPUFA in infancy on childhood cognition is not known.     

The relationship between plumage colouration,problem‐solving and learning performance in great tits Parus major

Recent studies suggest that individuals with better problem‐solving and/or learning performance have greater reproductive success, and that individuals may thus benefit from choosing mates based on these performances. However, directly assessing these performances in candidate mates could be difficult. Instead, the use of indirect cues related to problem‐solving and/or learning performance, such as condition‐dependent phenotypic traits, might be favored. We investigated whether problem‐solving and learning performance on a novel non‐foraging task correlated with sexually selected plumage colouration in a natural population of great tits Parus major. We found that males successful in solving the task had darker blue‐black crowns than non‐solvers, and that males solving the task more rapidly over multiple attempts (i.e. learners) exhibited blue‐black crowns with higher UV chroma and shorter‐wavelength hues than non‐learners. In contrast, we found no link between behavioural performance on the task and the yellow breast colouration in either sex. Our findings suggest that blue‐black crown colouration could serve as a signal of problem‐solving and learning performance in wild great tit males. Further research remains necessary to determine whether different sexually selected traits are used to signal cognitive performance for mate choice, either directly (i.e. cognitive performance influencing individual's health and ornamentation through diet for example) or indirectly (i.e. due to a correlation with a third factor such as individual quality or condition).     

Problem‐solving skills are linked to parental care and offspring survival in wild house sparrows

Individuals within a population often exhibit consistent differences in important behavioral traits such as parental care. One interesting, yet largely unexplored explanation for the existence of these consistent differences among parents is the idea that cognitive differences between individuals could lead to between‐individual variation in parenting behavior. I used a wild population of house sparrows (Passer domesticus) to test the nature of the relationship between aspects of cognitive ability (problem‐solving performance and learning) and parental care behavior, both measured in the wild. Furthermore, because parental care is tightly linked to fitness, I also investigated the relationship between problem‐solving performance and offspring survival. Parent sparrows were presented with a novel problem‐solving task that required them to remove an obstacle to obtain food. While there was no relationship between the ability to complete the task and measures of parental care (nestling provisioning rate or likelihood of provisioning with large food items), parents that solved the task quickly had higher provisioning rates than slow solvers. Additionally, the ability of fathers to complete the problem‐solving task was positively related to offspring survival. These results provide evidence that aspects of problem‐solving performance are positively correlated with parenting behavior and fitness in the wild.     

Efficacy of Traumatic Brain Injury Rehabilitation: Interventions of QEEG-guided Biofeedback,Computers, Strategies,and Medications

The onset of cognitive rehabilitation brought with it a hope for an effective treatment for the traumatic brain injured subject. This paper reviews the empirical reports of changes in cognitive functioning after treatment and compares the relative effectiveness of several treatments including computer interventions, cognitive strategies, EEG biofeedback, and medications. The cognitive functions that are reviewed include auditory memory, attention and problem solving. The significance of the change in cognitive function is assessed in two ways that include effect size and longevity of effect. These analyses complement the previously published meta-reviews by adding these two criteria and include reports of EEG biofeedback, which is shown to be an effective intervention for auditory memory.     

材料性质和专业对解决四卡片问题影响的眼动研究

目的：探讨实验材料性质和专业背景等因素对四卡片推理问题解决的影响。方法：使用ASL-504眼动记录仪,以16名大学生为被试,采用2（材料性质）×2（专业）的二因素被试间设计。结果：材料性质主效应不显著,但材料性质在相对注视时间、相对注视次数和瞳孔直径上呈现显著差异;专业因素主效应显著,专业因素在平均注视时间和平均眼跳距离上差异显著,二因素交互作用不显著;＂如果子句＂和＂那么子句＂在所有眼动指标上不存在显著差异。结论：（1）抽象程度高的材料在理解四卡片问题时需要更多的加工,包括条件句及其组成部分;（2）不同专业背景对理解条件句有不同的影响;（3）条件句各组成部分在理解时得到同等重要的加工。     

Pavlovian extinction, phobias, and the limits of the cognitive paradigm

The slow or total lack of decrease in some autonomic responses during extinction in aversive conditioning and concomitant verbalization of fear have remained a problem for learning theories and psychophysiology. Removal of the aversive stimulus should result in a rapid decrement in responding, as it does in cognitive and somatic systems. In laboratory analogues of phobia and clinical neurosis, however, such decreases do not occur in some autonomic responses and reported fear. In this article three areas of research are presented in which dissociations occur between cognitive and autonomic responses: 1) relational learning, 2) phobia, and 3) incubation. The data indicate that there are some important distinctions to be made concerning the properties of different psychological and physiological systems. These distinctions pertain to the differences between cognitive and noncognitive systems, between the two branches of the ANS, and between acquisition and extinction processes. These distinctions lead to a number of hypotheses concerning dissociations between response systems and have important implications for the understanding and treatment of neurosis.     

A unifying theory on the relationship between spike trains,EEG, and ERP based on the noise shaping/predictive neural coding hypothesis

Cracking the neural code has long been a central issue in neuroscience. However, it has been proved difficult because there logically exist an infinite number of other models and interpretations that could account for the same data and phenomena (i.e. the problem of underdetermination). Therefore, I suggest that applying biologically realistic multiple constraints from ion-channel level to system level (e.g. cognitive neuroscience and human brain disorders) can only solve the problem of underdetermination. Here I have explored whether the noise shaping/predictive neural coding hypothesis can provide a unified view on following realistic multiple constraints: (1) cortical gain control mechanisms in vivo; (2) the relationships between acetylcholine, nicotine, dopamine, calcium-activated potassium ion-channel, and cognitive functions; (3) oscillations and synchrony; (4) why should spontaneous activity be irregular; (5) whether the cortical neurons in vivo are coincidence detectors or integrators; and (6) the causal relationship between theta oscillation, gamma band fluctuation, and P3 (or P300) ERP responses. Finally, recent experimental results supporting the unified view shall be discussed.     

The OR and significance

A brief review was conducted of past and current research and theory as well as future implications of the problem of significance and the OR. Research and theory in the field is judged to be at a choice point: advance to interesting and important problems integrated with biobehavioral research or enter a blind alley of pseudo-problems derived from computer metaphors and cognitive folk psychology.     

Will cognitive enhancement create post‐persons? The use(lessness) of induction in determining the likelihood of moral status enhancement

The prospect of cognitive enhancement well beyond current human capacities raises worries that the fundamental equality in moral status of human beings could be undermined. Cognitive enhancement might create beings with moral status higher than persons. Yet, there is an expressibility problem of spelling out what the higher threshold in cognitive capacity would be like. Nicholas Agar has put forward the bold claim that we can show by means of inductive reasoning that indefinite cognitive enhancement will probably mark a difference in moral status. The hope is that induction can determine the plausibility of post‐personhood existence in the absence of an account of what the higher status would be like. In this article, we argue that Agar's argument fails and, more generally, that inductive reasoning has little bearing on assessing the likelihood of post‐personhood in the absence of an account of higher status. We conclude that induction cannot bypass the expressibility problem about post‐persons.     

A Population-based study of dementia in the oldest old: the Monzino 80-plus Study

Background

Despite being the fastest growing and the most cognitively impaired age group, the oldest olds are under-represented in clinical research. The purpose of this study was to describe the design, methods, and baseline characteristics of the survey population and investigate possible differences in demographic, cognitive, functional, and behavioral characteristics between oldest old with and without any performance on cognitive tests and between oldest old alive and those deceased prior to the interview.

Methods

The Monzino 80-plus Study is a prospective door-to-door population-based survey among 80 years or older residents in the municipalities in the province of Varese, Italy. Dementia cases were identified with a one-phase design. Trained psychologists interviewed both the subject and a proxy informant. The interview included a comprehensive standardized questionnaire together with an array of rating scales and a multidomain cognitive battery to assess cognitive and functional ability, behavioral disturbances and mood.

Results

Information was available for 2,139 of the 2,428 registered individuals aged 80 years or older. Main baseline characteristics of the population are reported and discussed. In comparison with those living, elderly persons who had died before the first visit were older, had twice the rate of institutionalization, poorer cognitive performance and competence, and significantly greater instrumental and basic functional disability. The percentage of elderly persons, alive at baseline, without Mini-Mental State Examination rose rather evenly with age. Moreover, they had significantly worse cognitive competence and functional ability, and reported higher prevalences of depressive symptoms and problem behaviors than those with Mini-Mental State Examination.

Conclusions

Prospective investigation of a large population of oldest old can contribute significantly to understanding the relations between age, cognitive decline, and dementia occurrence. Use of informant-based instruments in surveys in the oldest old is crucial in assessing everyday functioning and changes, especially in participants with no cognitive test performance available. Failure to include information on deceased elderly would underestimate, increasingly with age, the prevalence of cognitive and functional disability in the elderly population.     

Quantum-like formalism for cognitive measurements

We develop a quantum formalism (Hilbert space probabilistic calculus) for measurements performed over cognitive systems. In particular, this formalism is used for mathematical modelling of the functioning of consciousness as a self-measuring quantum-like system. By using this formalism, we could predict averages of cognitive observables. Reflecting the basic idea of neurophysiological and psychological studies on a hierarchic structure of cognitive processes, we use p-adic hierarchic trees as a mathematical model of a mental space. We also briefly discuss the general problem of the choice of an adequate mental geometry.     

A novel biologically and psychologically inspired fuzzy decision support system: hierarchical complementary learning

A computational intelligent system that models the human cognitive abilities may promise significant performance in problem learning because human is effective in learning and problem solving. Functionally modelling the human cognitive abilities not only avoids the details of the underlying neural mechanisms performing the tasks, but also reduces the complexity of the system. The complementary learning mechanism is responsible for human pattern recognition, i.e. human attends to positive and negative samples when making decision. Furthermore, human concept learning is organized in a hierarchical fashion. Such hierarchical organization allows the divide-and-conquer approach to the problem. Thus, integrating the functional models of hierarchical organization and complementary learning can potentially improve the performance in pattern recognition. Hierarchical complementary learning (HCL) exhibits many of the desirable features of pattern recognition. It is further supported by the experimental results that verify the rationale of the integration and that the HCL system is a promising pattern recognition tool.