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Temporal variability is a fundamental property of brain processes and is functionally important to human cognition. This study examined how fluctuations in neural oscillatory activity are related to problem-solving performance as one example of how temporal variability affects high-level cognition. We used volatility to assess step-by-step fluctuations of EEG spectral power while individuals attempted to solve word-association puzzles. Inspired by recent results with hidden-state modeling, we tested the hypothesis that spectral-power volatility is directly associated with problem-solving outcomes. As predicted, volatility was lower during trials solved with insight compared with those solved analytically. Moreover, volatility during prestimulus preparation for problem-solving predicted solving outcomes, including solving success and solving time. These novel findings were replicated in a separate data set from an anagram-solving task, suggesting that less-rapid transitions between neural oscillatory synchronization and desynchronization predict better solving performance and are conducive to solving with insight for these types of problems. Thus, volatility can be a valuable index of cognition-related brain dynamics. [ABSTRACT FROM AUTHOR]

To solve a new problem, people spontaneously engage multiple cognitive processes. Previous work has identified a diverse set of oscillatory components critical at different stages of creative problem solving. In this project, we use hidden state modeling to untangle the roles of oscillation processes over time as people solve puzzles. Building on earlier work, we further developed analytical methods, such as incorporating source separating techniques and identifying the optimal number of states using cross-validation. We extracted brain states characterized by spatio-spectral topographies from time-resolved EEG spectral powers. The data driven approach allowed us to infer the dynamic, trial-by-trial, state sequences, and provided a comprehensive depiction of how various oscillation components interact recurrently throughout the trial. The properties of the states suggest their dissociable cognitive functions. For example, we identified three states with dominant activation in alpha bands but having distinct spatial distributions. People were differentially engaged in these states depending on the stages (e.g., onset or response) and outcomes of the trials (solved with insight or analysis). The current approach, applicable to many tasks requiring extended trial duration, can potentially reconcile findings from previous EEG studies and drive new hypotheses to further our understanding of the complex creative process. [ABSTRACT FROM AUTHOR]

Insight occurs when a person suddenly reinterprets a stimulus, situation, or event to produce a nonobvious, nondominant interpretation. This can take the form of a solution to a problem (an 'aha moment'), comprehension of a joke or metaphor, or recognition of an ambiguous percept. Insight research began a century ago, but neuroimaging and electrophysiological techniques have been applied to its study only during the past decade. Recent work has revealed insight-related coarse semantic coding in the right hemisphere and internally focused attention preceding and during problem solving. Individual differences in the tendency to solve problems insightfully rather than in a deliberate, analytic fashion are associated with different patterns of resting-state brain activity. Recent studies have begun to apply direct brain stimulation to facilitate insight. In sum, the cognitive neuroscience of insight is an exciting new area of research with connections to fundamental neurocognitive processes. [ABSTRACT FROM AUTHOR]

A sudden comprehension that solves a problem, reinterprets a situation, explains a joke, or resolves an ambiguous percept is called an insight (i.e., the “ Aha! moment”). Psychologists have studied insight using behavioral methods for nearly a century. Recently, the tools of cognitive neuroscience have been applied to this phenomenon. A series of studies have used electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) to study the neural correlates of the “ Aha! moment” and its antecedents. Although the experience of insight is sudden and can seem disconnected from the immediately preceding thought, these studies show that insight is the culmination of a series of brain states and processes operating at different time scales. Elucidation of these precursors suggests interventional opportunities for the facilitation of insight. [ABSTRACT FROM AUTHOR]

Abstract: Semantic richness refers to the amount of semantic information associated with a concept. Reaction-time (RT) studies have shown that words referring to rich concepts elicit faster responses than those referring to impoverished ones, suggesting that richer concepts are activated more quickly. In a recent functional neuroimaging study, richer concepts evoked less neural activity, which was interpreted as faster activation. The interpretations of these findings appear to conflict with event-related potential (ERP) studies showing no evidence that speed of concept activation is influenced by typical semantic variables. Resolution of this apparent contradiction is important because the interpretation of 40 years of semantic-memory RT studies depends on whether factors such as semantic richness influence the duration of initial concept activation or later decision and response processes. Consistent with previous studies of the effects of semantic factors on ERP, the present study shows that richness influences the magnitude, but not the latency, of the P2 and N400 ERP components (which are early relative to behavioral responses), suggesting that effects of richness on RT reflect temporal effects on downstream decision or response mechanisms rather than on upstream concept activation. [Copyright &y& Elsevier]

Previous research has shown that people solve insight or creative problems better when in a positive mood (assessed or induced), although the precise mechanisms and neural substrates of this facilitation remain unclear. We assessed mood and personality variables in 79 participants before they attempted to solve problems that can be solved by either an insight or an analytic strategy. Participants higher in positive mood solved more problems, and specifically more with insight, compared with participants lower in positive-mood. fMRI was performed on 27 of the participants while they solved problems. Positive mood (and to a lesser extent and in the opposite direction, anxiety) was associated with changes in brain activity during a preparatory interval preceding each solved problem; modulation of preparatory activity in several areas biased people to solve either with insight or analytically. Analyses examined whether (a) positive mood modulated activity in brain areas showing responsivity during preparation; (b) positive mood modulated activity in areas showing stronger activity for insight than noninsight trials either during preparation or solution; and (c) insight effects occurred in areas that showed mood-related effects during preparation. Across three analyses, the ACC showed sensitivity to both mood and insight, demonstrating that positive mood alters preparatory activity in ACC, biasing participants to engage in processing conducive to insight solving. This result suggests that positive mood enhances insight, at least in part, by modulating attention and cognitive control mechanisms via ACC, perhaps enhancing sensitivity to detect non-prepotent solution candidates. [ABSTRACT FROM AUTHOR]

Abstract: Accumulating evidence suggests that top-down processes, reflected by frontal-midline theta-band (4–8 Hz) electroencephalogram (EEG) oscillations, strengthen the activation of a memory set during short-term memory (STM) retention. In addition, the amplitude of posterior alpha-band (8–13 Hz) oscillations during STM retention is thought to reflect a mechanism that protects fragile STM activations from interference by gating bottom-up sensory inputs. The present study addressed two important questions about these phenomena. First, why have previous studies not consistently found memory set-size effects on frontal-midline theta? Second, how does posterior alpha participate in STM retention? To answer these questions, large-scale network connectivity during STM retention was examined by computing EEG wavelet coherence during the retention period of a modified Sternberg task using visually-presented letters as stimuli. The results showed (a) increasing theta-band coherence between frontal-midline and left temporal-parietal sites with increasing memory load, and (b) increasing alpha-band coherence between midline parietal and left temporal/parietal sites with increasing memory load. These findings support the view that theta-band coherence, rather than amplitude, is the key factor in selective top-down strengthening of the memory set and demonstrate that posterior alpha-band oscillations associated with sensory gating are involved in STM retention by participating in the STM network. [Copyright &y& Elsevier]

Abstract: People can solve problems in more than one way. Two general strategies involve (A) methodical, conscious, search of problem-state transformations, and (B) sudden insight, with abrupt emergence of the solution into consciousness. This study elucidated the influence of initial resting brain-state on subjects’ subsequent strategy choices. High-density electroencephalograms (EEGs) were recorded from subjects at rest who were subsequently directed to solve a series of anagrams. Subjects were divided into two groups based on the proportion of anagram solutions derived with self-reported insight versus search. Reaction time and accuracy results were consistent with different cognitive problem-solving strategies used for solving anagrams with versus without insight. Spectral analyses yielded group differences in resting-state EEG supporting hypotheses concerning insight-related attentional diffusion and right-lateralized hemispheric asymmetry. These results reveal a relationship between resting-state brain activity and problem-solving strategy, and, more generally, a dependence of event-related neural computations on the preceding resting state. [Copyright &y& Elsevier]

Insight occurs when problem solutions arise suddenly and seem obviously correct, and is associated with an “Aha!” experience. Prior theorizing concerning preparation that facilitates insight focused on solvers' problem-specific knowledge. We hypothesized that a distinct type of mental preparation, manifested in a distinct brain state, would facilitate insight problem solving independently of problem-specific knowledge. Consistent with this hypothesis, neural activity during a preparatory interval before subjects saw verbal problems predicted which problems they would subsequently solve with, versus without, self-reported insight. Specifically, electroencephalographic topography and frequency (Experiment 1) and functional magnetic resonance imaging signal (Experiment 2) both suggest that mental preparation leading to insight involves heightened activity in medial frontal areas associated with cognitive control and in temporal areas associated with semantic processing. The results for electroencephalographic topography suggest that noninsight preparation, in contrast, involves increased occipital activity consistent with an increase in externally directed visual attention. Thus, general preparatory mechanisms modulate problem-solving strategy. [ABSTRACT FROM AUTHOR]

Effects of conceptual fusion on episodic associative retrieval were examined. Subjects attempted to fuse sequentially displayed (800 ms offset) word pairs; pairs subjects were unable to fuse were instead considered associated by juxtaposition. Next, dense-array event-related potentials (ERPs) were recorded while the pairs were redisplayed, half reversed in order. Subjects pressed a button to indicate whether each pair was presented in the previous order. Behavioral results showed that retrieval of fused pairs was faster and more accurate than for juxtaposed pairs. ERP topography to the first word of fused pairs was different from juxtaposed pairs, indicating that fusion can mediate associative retrieval of constituent items. Estimates of current source density at the cortical surface showed that fusion-mediated retrieval elicited left inferior-prefrontal/anterior-temporal activity not typically observed in episodic memory retrieval studies. [Copyright &y& Elsevier]

Semantic memory consolidation was studied by comparing medial temporal lobe (MTL) fMRI activation to ANIMAL, IMPLEMENT and ABSTRACT nouns in healthy seniors to that of young adults. Relative to healthy seniors, young adults were predicted to show greater MTL activation for IMPLEMENTS, but not ANIMALS, because the ANIMALS category consists of highly intercorrelated and overlapping features that should require less MTL-mediated binding than IMPLEMENTS over a shorter period of time during concept consolidation. ABSTRACT meanings are context-dependent and do not consist of fixed feature sets. Thus it was predicted that ABSTRACT words would not involve age-related feature binding mediated by the MTL. These predictions were confirmed by the results. Our observations are consistent with the hypothesis that the structure of a category influences the consolidation of knowledge in semantic memory. [Copyright &y& Elsevier]

Sometimes, a thousand words isn''t worth a picture. A recent study by West and Holcomb used event-related potentials to examine non-verbal, discourse-level processing of stories presented as picture sequences. These complex pictures were presented at a rapid rate, thereby minimizing linguistic mediation. The ERP showed N300 and N400 deflections, hypothesized to reflect image activation and amodal semantic integration, respectively. [ABSTRACT FROM AUTHOR]

Explores the semantic satiation effect using the event-related brain potential (ERP) technique. Neural substrates of semantic satiation when the primes and target are presented in the same modality; Interacting effects of prime satiation and relatedness of the primes to the critical word on ERP amplitude; Modulation of N400 relatedness effect by prime satiation.

Examines whether semantic relations are atomistic unitary associations or are complex concepts consisting of a number of relational elements. Relations in semantic memory; Speed-accuracy decomposition; Stimulus generation; Alternate interpretations; Exemplar model; Continuous probabilities assigned to unitary tasks; Timer model; Future directions.

Presents experiments demonstrating discrete and continuing cognitive information processes in an anagram task. Investigation on the time course of information processing with use of speed-accuracy decomposition (SAD); Discrete transmission of information in an insight-like task.

Examines the time course of source-monitoring judgments about perceived and imagined recognition. Use of response-signal procedure in the evaluation of time course effects; Old-new recognition accuracy; Development of source-identification accuracy; Differences of the memories for imagined and perceived events with respect to the relative amounts of various types of information they conclude.

Discusses two experiments which reexamine the semantic processing of concrete and abstract words using an alternative experimental methodology, the measurement of event-related brain potentials (ERP). Dual-coding theory; Verbal and imaginal systems and their link with the left and right hemispheres of the brain; Context-availability theory; Context-availability model.

Loss-of-control (LOC) eating involves a subjective feeling that one cannot stop eating or control one's eating. Individuals with LOC eating may exhibit strong appetitive drives and weak inhibitory control, and these two opposing motivations have been related to EEG measurements of frontal asymmetry or lateralized frontal activation. The present study investigated whether frontal asymmetry is related to hedonic hunger, LOC eating severity and frequency, and eating in the absence of hunger (EAH) in the laboratory. Fifty-nine individuals participated in an ostensible taste study after resting-state electroencephalogram (EEG) recordings. After the EEGs, they were provided a meal to eat until fullness, followed by an array of snacks and instructions to eat as much as they would like. The results indicated that several measures of right-frontal asymmetry were related to greater EAH and greater self-reported LOC eating severity. Although right-frontal asymmetry has been theorized to reflect avoidance motivation, recent evidence suggests it may indicate effortful control during approach-avoidance conflicts. Because individuals with LOC eating presumably experience heightened conflict between drives to eat beyond energy needs and to minimize such eating, those experiencing greater LOC may exert greater effort to manage these conflicting motivations. An integration of these neurobiological correlates of LOC eating may help provide a more comprehensive understanding of LOC eating and inform treatments. [ABSTRACT FROM AUTHOR]

Brain age prediction based on imaging data and machine learning (ML) methods has great potential to provide insights into the development of cognition and mental disorders. Though different ML models have been proposed, a systematic comparison of ML models in combination with imaging features derived from different modalities is still needed. In this study, we evaluate the prediction performance of 36 combinations of imaging features and ML models including deep learning. We utilize single and multimodal brain imaging data including MRI, DTI, and rs‐fMRI from a large data set with 839 subjects. Our study is a follow‐up to the initial work (Liang et al., 2019. Human Brain Mapping) to investigate different analytic strategies to combine data from MRI, DTI, and rs‐fMRI with the goal to improve brain age prediction accuracy. Additionally, the traditional approach to predicting the brain age gap has been shown to have a systematic bias. The potential nonlinear relationship between the brain age gap and chronological age has not been thoroughly tested. Here we propose a new method to correct the systematic bias of brain age gap by taking gender, chronological age, and their interactions into consideration. As the true brain age is unknown and may deviate from chronological age, we further examine whether various levels of behavioral performance across subjects predict their brain age estimated from neuroimaging data. This is an important step to quantify the practical implication of brain age prediction. Our findings are helpful to advance the practice of optimizing different analytic methodologies in brain age prediction. [ABSTRACT FROM AUTHOR]

An underexplored aspect of the relationship between analogical reasoning and creativity is its phenomenology; in particular, the notion that analogical reasoning is related to insight and its associated "aha!" experience. However, the relationship between these phenomena has never been directly investigated. We adapted a set of verbal analogy stimuli for use as an insight task. Across the two experiments, participants reported stronger aha moments and greater representational change when reasoning about analogies with greater internal semantic distance, relative to those with greater internal semantic consistency. Aha strength increased linearly with changes in participants' verbal descriptions of the analogy over the course of each trial, indicating that aha experiences accompany changes in mental representation. The relationship between subjective difficulty and aha strength followed an inverted U-shaped function, with aha strength increasing with greater difficulty but dropping at the highest levels. A similar pattern was observed for the relationship between confidence and aha strength. Furthermore, participants in a more positive mood rated aha experiences as stronger. These findings provide evidence that analogical reasoning can give rise to the phenomenology of insight by triggering representational change and suggest that the affective consequences of relational reasoning may play an important role in promoting creative cognition. [ABSTRACT FROM AUTHOR]

A history of dieting to lose weight has been shown to be a robust predictor of future weight gain. A potential factor in propensity towards weight gain is the nature of people's reactions to the abundance of highly palatable food cues in the environment. Event Related Potentials (ERPs) have revealed differences in how the brain processes food cues between obese and normal weight individuals, as well as between restrained and unrestrained eaters. However, comparisons by weight status are not informative regarding whether differences predate or follow weight gain in obese individuals and restrained eating has not consistently been found to predict future weight gain. The present study compared ERP responses to food cues in non-obese historic dieters (HDs) to non-obese never dieters (NDs). HDs showed a blunted N1 component relative to NDs overall, and delayed N1 and P2 components compared to NDs in the hungry state, suggesting that early, perceptual processing of food cues differs between these groups, especially when food-deprived. HDs also showed a more hunger-dependent sustained ERP (LPP) compared to NDs. Future research should test ERP-based food cue responsivity as a mediator between dieting history and future weight gain to better identify those most at risk for weight gain as well as the nature of their vulnerability. [ABSTRACT FROM AUTHOR]

How accurate are insights compared to analytical solutions? In four experiments, we investigated how participants' solving strategies influenced their solution accuracies across different types of problems, including one that was linguistic, one that was visual and two that were mixed visual-linguistic. In each experiment, participants' self-judged insight solutions were, on average, more accurate than their analytic ones. We hypothesised that insight solutions have superior accuracy because they emerge into consciousness in an all-or-nothing fashion when the unconscious solving process is complete, whereas analytic solutions can be guesses based on conscious, prematurely terminated, processing. This hypothesis is supported by the finding that participants' analytic solutions included relatively more incorrect responses (i.e., errors of commission) than timeouts (i.e., errors of omission) compared to their insight responses. [ABSTRACT FROM PUBLISHER]

When people try to solve a problem, they go through distinct steps (encoding, ideation, evaluation, etc.) recurrently and spontaneously. To disentangle different cognitive processes that unfold throughout a trial, we applied an unsupervised machine learning method to electroencephalogram (EEG) data continuously recorded while 39 participants attempted 153 Compound Remote Associates problems (CRA). CRA problems are verbal puzzles that can be solved in either insight-leaning or analysis-leaning manner. We fitted a Hidden Markov Model to the time-frequency transformed EEG signals and decoded each trial as a time-resolved state sequence. The model characterizes hidden brain states with spectrally resolved power topography. Seven states were identified with distinct activation patterns in the theta (4–7 Hz), alpha (8–9 Hz and 10–13 Hz), and gamma (25–50 Hz) bands. Notably, a state featuring widespread activation only in alpha-band frequency emerged, from this data-driven approach, which exhibited dynamic characteristics associated with specific temporal stages and outcomes (whether solved with insight or analysis) of the trials. The state dynamics derived from the model overlap and extend previous literature on the cognitive function of alpha oscillation: the " alpha-state " probability peaks before stimulus onset and decreases before response. In trials solved with insight, relative to solved with analysis, the alpha-state is more likely to be visited and maintained during preparation and solving periods, and its probability declines more sharply immediately preceding a response. This novel paradigm provides a way to extract dynamic features that characterize problem-solving stages and potentially provide a novel window into the nature of the underlying cognitive processes. [ABSTRACT FROM AUTHOR]

Using a creative production task, jazz improvisation, we tested alternative hypotheses about the flow experience: (A) that it is a state of domain-specific processing optimized by experience and characterized by minimal interference from task-negative default-mode network (DMN) activity versus (B) that it recruits domain-general task-positive DMN activity supervised by the fronto-parietal control network (FPCN) to support ideation. We recorded jazz guitarists' electroencephalograms (EEGs) while they improvised to provided chord sequences. Their flow-states were measured with the Core Flow State Scale. Flow-related neural sources were reconstructed using SPM12. Over all musicians, high-flow (relative to low-flow) improvisations were associated with transient hypofrontality. High-experience musicians' high-flow improvisations showed reduced activity in posterior DMN nodes. Low-experience musicians showed no flow-related DMN or FPCN modulation. High-experience musicians also showed modality-specific left-hemisphere flow-related activity while low-experience musicians showed modality-specific right-hemisphere flow-related deactivations. These results are consistent with the idea that creative flow represents optimized domain-specific processing enabled by extensive practice paired with reduced cognitive control. • The flow state has been described as effortless attention to a task. • Few studies have examined the neural basis of flow during creative production. • We examined flow-related neural activity by recording EEGs during jazz improvisation. • High-flow versus low-flow is associated with greater left-hemisphere activity and reduced frontal and default-mode activity. • The results support the view that creative flow is a state of optimized, domain-specific processing. [ABSTRACT FROM AUTHOR]

Abstract: Much work has investigated the neural representation of specific categories of knowledge, but relatively scant attention has been paid in the cognitive neuroscience literature to the semantic processes that contribute to semantic memory. In this study, we monitored regional cortical activity with fMRI while healthy young adults evaluated visually displayed NATURAL KIND, ARTIFACT, and ABSTRACT nouns with two standard tasks: Typicality judgments and Pleasantness judgments. We observed a significant interaction effect between the category of knowledge and the type of judgment used to evaluate members of these semantic categories. Typicality judgments recruited greater temporal–occipital activation relative to Pleasantness judgments of the same category, and this was seen for comparisons of all three semantic categories. However, when contrasted with Typicality judgments, Pleasantness judgments activated a different anatomic distribution for each semantic category. These findings are consistent with a dynamic approach to semantic memory that includes at least two components: semantic knowledge and semantic processes that interpret this knowledge in several ways depending on the particular semantic challenge. [Copyright &y& Elsevier]

This study examined the effects of acute stress on creative problem-solving. Thirty-five male participants underwent stress induction via the Trier Social Stress Test; another 35 male participants engaged in a comparable, but less stressful, control task. Subsequently, they all took the Alternative Uses Test (AUT) and the Remote Associates Test (RAT), both of which are standard creative problem-solving tasks. Heart rate (HR) and salivary cortisol were recorded at regular intervals. Compared to controls, stressed participants responded with higher HR and salivary cortisol and reported more negative affect. A comparison of the effects of acute stress on two forms of creative problem-solving tasks, convergent and divergent problem-solving, showed stress-related reductions in the flexibility of solving. These effects were manifested according to the nature of the tasks: in convergent solving, stress induced faster, but less accurate responding; in divergent solving, stress reduced the flexibility of solution production, resulting in less variety of solutions. [ABSTRACT FROM AUTHOR]

Abstract Anecdotal reports suggest the existence of individual differences in peoples' cognitive styles for solving problems, in particular, the tendency to rely on insight (the "aha" phenomenon) versus deliberate analytical thought. We hypothesized that such stable individual differences exist and are associated with trait-like individual differences in resting-state brain activity. We tested this idea by recording participants' resting-state electroencephalograms (RS-EEGs) on 4 occasions over approximately 7 weeks and then tasking them with solving anagrams and compound remote associates problems that are solvable by either strategy. We found that peoples' tendency to solve problems consistently by insight or by analysis spans both tasks and time. Moreover, we discovered trait-like individual differences in the balance between frontal and posterior resting-state brain activity and in temporal-lobe hemispheric asymmetries that predict, at least weeks in advance, the tendency to solve by insight versus analysis. The discovery of an insight-analytic dimension of cognitive style and its neural basis in resting state brain activity suggests new avenues for the development of neuroscience-based methods for intellectual, educational, and vocational assessment. Highlights • The tendency to use insight or analytic thinking to solve problems is trait-like. • Individuals' resting brainwave patterns predict which method they use more. • Analytic solvers exhibit greater frontal resting-state beta-band power. • Insightful solvers exhibit more left parietal beta and left-temporal theta/alpha. • A brainwave model can predict which strategy a person relies on weeks in advance. [ABSTRACT FROM AUTHOR]

Current creativity research reveals a fundamental disagreement about the nature of creative thought, specifically, whether it is primarily based on automatic, associative (Type 1) or executive, controlled (Type 2) cognitive processes. We propose that Type 1 and Type 2 processes make differential contributions to creative production depending on domain expertise and situational factors such as task instructions. We tested this hypothesis with jazz pianists who were instructed to improvise to a novel chord sequence and rhythm accompaniment. Afterward, they were asked to perform again under instructions to be especially creative which, via goal activation, is thought to prompt the musicians to engage Type 2 processes. Jazz experts rated all performances. Overall, performances by more experienced pianists were rated as superior. Moreover, creativity instructions resulted in higher ratings. However, there was an interaction between instructions and expertise, revealing that explicit creativity instructions significantly improved improvisation ratings only for the less experienced musicians. We propose that activating or reconfiguring executive Type 2 processes facilitates creativity for less experienced musicians, but does not improve creative performance significantly for more experienced ones because the latter have largely automatized the processes responsible for high-level improvisation or because they have achieved a near-optimal balance between associative Type 1 and executive Type 2 processes. Thus, increasing controlled Type 2 processing is unlikely to help, and may sometimes even diminish, the creativity of experts' performances. [ABSTRACT FROM AUTHOR]

Creative ideas seem often to appear when we close our eyes, stare at a blank wall, or gaze out of a window-all signs of shutting out distractions and turning attention inward. Prior research has demonstrated that attention-related brain areas are differently active when people solve problems with sudden insight (the Aha! phenomenon), relative to deliberate, analytic solving. We directly investigated the relationship between attention deployment and problem solving by recording eye movements and blinks, which are overt indicators of attention, as people solved short, visually presented problems. In the preparation period, before problems eventually solved by insight, participants blinked more frequently and longer, and made fewer fixations, than before problems eventually solved by analysis. Immediately prior to solutions, participants blinked longer and looked away from the problem more often when solving by insight than when solving analytically. These phenomena extend prior research with a direct demonstration of dynamic differences in attention as people solve problems with sudden insight versus analytically. [ABSTRACT FROM AUTHOR]

Introduction Reductions of cerebrospinal fluid (CSF) amyloid-beta (Aβ42) and elevated phosphorylated-tau (p-Tau) reflect in vivo Alzheimer׳s disease (AD) pathology and show utility in predicting conversion from mild cognitive impairment (MCI) to dementia. We investigated the P50 event-related potential component as a noninvasive biomarker of AD pathology in non-demented elderly. Methods 36 MCI patients were stratified into amyloid positive (MCI-AD, n =17) and negative (MCI-Other, n =19) groups using CSF levels of Aβ42. All amyloid positive patients were also p-Tau positive. P50s were elicited with an auditory oddball paradigm. Results MCI-AD patients yielded larger P50s than MCI-Other. The best amyloid-status predictor model showed 94.7% sensitivity, 94.1% specificity and 94.4% total accuracy. Discussion P50 predicted amyloid status in MCI patients, thereby showing a relationship with AD pathology versus MCI from another etiology. The P50 may have clinical utility for inexpensive pre-screening and assessment of Alzheimer׳s pathology. [ABSTRACT FROM AUTHOR]

There are two general strategies for solving a problem. Insight is the sudden realization of a novel idea or problem solution accompanied by an "aha" experience. Analysis occurs in a conscious, deliberate fashion without an "aha" experience. Previous research has shown that brain activity during a preparatory period immediately before a problem is presented can predict whether the subsequently presented problem will be solved by insight or by analysis. Those prior studies used a type of brief verbal problem called compound remote associates (CRA). To determine whether prestimulus activity predicts subsequent insight versus analytic solving for other types of problems, the present study used an anagram task. We examined high-density electroencephalograms (EEGs) immediately preceding the presentation of anagrams and found that during the 2-s prestimulus interval there was greater beta-band activity recorded over right central-parietal cortex prior to analytic solving compared with insightful solving. EEG source reconstruction showed that this activity originated in left mid-cingulate cortex (MCC) and the right postcentral gyrus. In contrast to prior work, we found no evidence of a significant interaction between insight-related prestimulus brain activity and positive mood, although positive mood was associated with greater activity in anterior cingulate cortex and with a larger number of insight solutions. The present MCC results suggest that participants' anagram-solving strategies may be influenced by allostasis , that is, the estimation and marshalling of neurocognitive resources required to cope with an expected task. Specifically, when a participant adequately prepares for an upcoming problem, then MCC activity is high, enabling solution by resource-intensive analytic processing. Alternatively, when preparation is insufficient for analytic processing, then MCC activity is low and subsequent solving occurs by low-demand insight processing. The current findings and explanatory model differ from those of previous studies that used a CRA task, suggesting the possibility of complex interactions between task-type and procedure-type in determining the nature of prestimulus preparation. Future research examining such interactions may yield results that benefit educators who teach students problem-solving strategies. • People can solve problems using insight or analytic strategies. • Solving strategy selection is influenced by pre-problem brain activity. • Preparatory pre-problem brain activity varies with the type of task. • Analytic solving of anagrams follows mid-cingulate cortex preparatory activity. • Mid-cingulate activity is thought to reflect allostasis, the priming of needed resources. [ABSTRACT FROM AUTHOR]

Behavioral and neuroimaging findings indicate that distinct cognitive and neural processes underlie solving problems with sudden insight. Moreover, people with less focused attention sometimes perform better on tests of insight and creative problem solving. However, it remains unclear whether different states of attention, within individuals, influence the likelihood of solving problems with insight or with analysis. In this experiment, participants (N = 40) performed a baseline block of verbal problems, then performed one of two visual tasks, each emphasizing a distinct aspect of visual attention, followed by a second block of verbal problems to assess change in performance. After participants engaged in a center-focused flanker task requiring relatively focused visual attention, they reported solving more verbal problems with analytic processing. In contrast, after participants engaged in a rapid object identification task requiring attention to broad space and weak associations, they reported solving more verbal problems with insight. These results suggest that general attention mechanisms influence both visual attention task performance and verbal problem solving. [ABSTRACT FROM AUTHOR]

This study compared two theoretically opposed strategies for acute pain management: an acceptance-based and a change-based approach. These two strategies were compared in a within-subjects design using the cold pressor test as an acute pain induction method. Participants completed a baseline pain tolerance assessment followed by one of the two interventions and another pain tolerance test. The alternate strategy was presented in a separate, but otherwise identical, experimental session. On average, both interventions significantly increased pain tolerance relative to baseline, with no significant difference between the two intervention conditions. Baseline psychological acceptance emerged as a significant moderator of intervention efficacy; individuals with a high level of acceptance benefited significantly more from the acceptance intervention, whereas those with a low level of acceptance benefited more from the change-based intervention. Implications for increasing the effectiveness of psychotherapeutic treatments based on individual differences are discussed. [ABSTRACT FROM PUBLISHER]

Abstract: Dietary restraint is heavily influenced by affect, which has been independently related to asymmetrical activation in the prefrontal cortex (prefrontal asymmetry) in electroencephalograph (EEG) studies. In normal weight individuals, dietary restraint has been related to prefrontal asymmetry; however, this relationship was not mediated by affect. This study was designed to test the hypotheses that, in an overweight and obese sample, dietary restraint as well as binge eating, disinhibition, hunger, and appetitive responsivity would be related to prefrontal asymmetry independent of affect at the time of assessment. Resting EEG recordings and self-report measures of overeating and affect were collected in 28 overweight and obese adults. Linear regression analyses were used to predict prefrontal asymmetry from appetitive measures while controlling for affect. Cognitive restraint and binge eating were not associated with prefrontal asymmetry. However, disinhibition, hunger, and appetitive responsivity predicted left-, greater than right-, sided prefrontal cortex activation independent of affect. Findings in this study add to a growing literature implicating the prefrontal cortex in the cognitive control of dietary intake. Further research to specify the precise role of prefrontal asymmetry in the motivation toward, and cessation of, feeding in obese individuals is encouraged. [Copyright &y& Elsevier]

Abstract: As the number of the elderly population affected by Alzheimer’s disease (AD) rises rapidly, the need to find an accurate, inexpensive and non-intrusive diagnostic procedure that can be made available to community healthcare providers is becoming an increasingly urgent public health concern. Several recent studies have looked at analyzing electroencephalogram (EEG) signals through the use of wavelets and neural networks. While showing great promise, the final outcomes of these studies have been largely inconclusive. This is mostly due to inherent difficulty of the problem, but also – perhaps – due to inefficient use of the available information, as many of these studies have used a single EEG channel for the analysis. In this contribution, we describe an ensemble of classifiers based data fusion approach to combine information from two or more sources, believed to contain complementary information, for early diagnosis of Alzheimer’s disease. Our emphasis is on sequentially generating an ensemble of classifiers that explicitly seek the most discriminating information from each data source. Specifically, we use the event related potentials recorded from the Pz, Cz, and Fz electrodes of the EEG, decomposed into different frequency bands using multiresolution wavelet analysis. The proposed data fusion approach includes generating multiple classifiers trained with strategically selected subsets of the training data from each source, which are then combined through a modified weighted majority voting procedure. The implementation details and the promising outcomes of this implementation are presented. [Copyright &y& Elsevier]

Early diagnosis of Alzheimer's disease (AD) is becoming an increasingly important healthcare concern. Prior approaches analyzing event-related potentials (ERPs) had varying degrees of success, primarily due to smaller study cohorts, and the inherent difficulty of the problem. A new effort using multiresolution analysis of ERPs is described. Distinctions of this study include analyzing a larger cohort, comparing different wavelets and different frequency bands, using ensemble-based decisions and, most importantly, aiming the earliest possible diagnosis of the disease. Surprising yet promising outcomes indicate that ERPs in response to novel sounds of oddball paradigm may be more reliable as a biomarker than the more commonly used responses to target sounds. [ABSTRACT FROM AUTHOR]

Neurofeedback (NF) is an electroencephalographic (EEG) biofeedback technique for training individuals to alter their brain activity via operant conditioning. Research has shown that NF helps reduce symptoms of several neurological and psychiatric disorders, with ongoing research currently investigating applications to other disorders and to the enhancement of non-disordered cognition. The present article briefly reviews the fundamentals and current status of NF therapy and research and illustrates the basic approach with an interim report on a pilot study aimed at developing a new NF protocol for improving cognitive function in the elderly. EEG peak alpha frequency (PAF) has been shown to correlate positively with cognitive performance and to correlate negatively with age after childhood. The present pilot study used a double-blind controlled design to investigate whether training older individuals to increase PAF would result in improved cognitive performance. The results suggested that PAF NF improved cognitive processing speed and executive function, but that it had no clear effect on memory. In sum, the results suggest that the PAF NF protocol is a promising technique for improving selected cognitive functions. [ABSTRACT FROM AUTHOR]

After a person has become stuck on a problem, they sometimes achieve a clear and sudden solution through insight – the so-called Aha! experience. Because of its distinctive experience, the origins and characteristics of insight have received considerable attention historically in psychological research. However, despite considerable progress in characterizing insight, the underlying mechanisms remain mysterious. We argue that research on insight could be greatly advanced by supplementing traditional insight research, which depends on a few complex problems, with paradigms common in other domains of cognitive science. We describe a large set of mini-insight problems to which multiple methods can be applied, together with subjective reports to identify insight problem-solving. Behavioral priming and neuroimaging methods are providing evidence about what, where, and how neural activity occurs during insight. Such evidence constrains theories of component processes, and will help to demystify insight. [Copyright &y& Elsevier]

People sometimes solve problems with a unique process called insight, accompanied by an "Aha!" experience. It has long been unclear whether different cognitive and neural processes lead to insight versus noninsight solutions, or if solutions differ only in subsequent subjective feeling. Recent behavioral studies indicate distinct patterns of performance and suggest differential hemispheric involvement for insight and noninsight solutions. Subjects solved verbal problems, and after each correct solution indicated whether they solved with or without insight. We observed two objective neural correlates of insight. Functional magnetic resonance imaging (Experiment 1) revealed increased activity in the right hemisphere anterior superior temporal gyrus for insight relative to noninsight solutions. The same region was active during initial solving efforts. Scalp electroencephalogram recordings (Experiment 2) revealed a sudden burst of high-frequency (gamma-band) neural activity in the same area beginning 0.3 s prior to insight solutions. This right anterior temporal area is associated with making connections across distantly related information during comprehension. Although all problem solving relies on a largely shared cortical network, the sudden flash of insight occurs when solvers engage distinct neural and cognitive processes that allow them to see connections that previously eluded them. Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) are used to study neural activity in subjects during a verbal task for which they report solutions achieved by insight. [ABSTRACT FROM AUTHOR]

Objective: Electroencephalographic (EEG) peak alpha frequency (PAF) (measured in Hz) has been correlated to cognitive performance between healthy and clinical individuals, and among healthy individuals. PAF also varies within individuals across developmental stages, among different cognitive tasks, and among physiological states induced by administration of various substances. The present study suggests that, among other things, PAF reflects a trait or state of cognitive preparedness.Methods: Experiment 1 involved 19-channel EEG recordings from 10 individuals with traumatic brain injury (TBI) and 12 healthy matched controls, before, during, and after tasks of visual and auditory attention. Experiment 2 involved EEG recordings from 19 healthy young adults before and after a working memory task (WAIS-R Digit Span), repeated on 2 different days to measure within-individual differences.Results: Experiment 1 showed significantly lower PAF in individuals with TBI, mostly during post-task rest. Experiment 2 showed PAF during pre-task baseline to be significantly correlated with Digit Span performance of the same day but not with Digit Span performance of another day. Moreover, PAF was significantly increased after Digit Span for those participants whose PAF was lower than the sample median before the task, but not for those who had it higher. Finally, both PAF and Digit Span performance were increased during the second day.Conclusions: PAF was shown to detect both trait and state differences in cognitive preparedness, as well as to be affected by cognitive tasks. Traits are better reflected during post-task rest, whereas states are better reflected during initial resting baseline recordings. [Copyright &y& Elsevier]

People sometimes solve problems with a unique process called insight, accompanied by an ''Aha!'' experience. It has long been unclear whether different cognitive and neural processes lead to insight versus noninsight solutions, or if solutions differ only in subsequent subjective feeling. Recent behavioral studies indicate distinct patterns of performance and suggest differential hemispheric involvement for insight and noninsight solutions. Subjects solved verbal problems, and after each correct solution indicated whether they solved with or without insight. We observed two objective neural correlates of insight. Functional magnetic resonance imaging (Experiment 1) revealed increased activity in the right hemisphere anterior superior temporal gyrus for insight relative to noninsight solutions. The same region was active during initial solving efforts. Scalp electroencephalogram recordings (Experiment 2) revealed a sudden burst of high-frequency (gamma-band) neural activity in the same area beginning 0.3 s prior to insight solutions. This right anterior temporal area is associated with making connections across distantly related information during comprehension. Although all problem solving relies on a largely shared cortical network, the sudden flash of insight occurs when solvers engage distinct neural and cognitive processes that allow them to see connections that previously eluded them. [ABSTRACT FROM AUTHOR]

Moments of insight, a phenomenon of creative cognition in which an idea suddenly emerges into awareness as an "Aha!" are often reported to be affectively positive experiences. We tested the hypothesis that problem-solving by insight is accompanied by neural reward processing. We recorded high-density EEGs while participants solved a series of anagrams. For each solution, they reported whether the answer had occurred to them as a sudden insight or whether they had derived it deliberately and incrementally (i.e., "analytically'). Afterwards, they filled out a questionnaire that measures general dispositional reward sensitivity. We computed the time-frequency representations of the EEGs for trials with insight (I) solutions and trials with analytic (A) solutions and subtracted them to obtain an I-A time-frequency representation for each electrode. Statistical Parametric Mapping (SPM) analyses tested for significant I-A and reward-sensitivity effects. SPM revealed the time, frequency, and scalp locations of several I ​> ​A effects. No A ​> ​I effect was observed. The primary neural correlate of insight was a burst of (I ​> ​A) gamma-band oscillatory activity over prefrontal cortex approximately 500 ​ms before participants pressed a button to indicate that they had solved the problem. We correlated the I-A time-frequency representation with reward sensitivity to discover insight-related effects that were modulated by reward sensitivity. This revealed a separate anterior prefrontal burst of gamma-band activity, approximately 100 ​ms after the primary I-A insight effect, which we interpreted to be an insight-related reward signal. This interpretation was supported by source reconstruction showing that this signal was generated in part by orbitofrontal cortex, a region associated with reward learning and hedonically pleasurable experiences such as food, positive social experiences, addictive drugs, and orgasm. These findings support the notion that for many people insight is rewarding. Additionally, these results may explain why many people choose to engage in insight-generating recreational and vocational activities such as solving puzzles, reading murder mysteries, creating inventions, or doing research. This insight-related reward signal may be a manifestation of an evolutionarily adaptive mechanism for the reinforcement of exploration, problem solving, and creative cognition. • Problem-solving by insight and analysis recruit different brain activity. • Reward sensitivity modulates brain activity during problem solving. • Insights evoke a neural reward signal in people high in reward sensitivity. • The insight reward signal is too quick to be conscious, post-solution appraisal. • This reward signal implies that creative cognition is intrinsically motivating. [ABSTRACT FROM AUTHOR]

Conflicting theories identify creativity either with frontal-lobe mediated (Type-2) executive control processes or (Type-1) associative processes that are disinhibited when executive control is relaxed. Musical (jazz) improvisation is an ecologically valid test-case to distinguish between these views because relatively slow, deliberate, executive-control processes should not dominate during high-quality, real-time improvisation. In the present study, jazz guitarists (n ​= ​32) improvised to novel chord sequences while 64-channel EEGs were recorded. Jazz experts rated each improvisation for creativity, technical proficiency and aesthetic appeal. Surface-Laplacian-transformed EEGs recorded during the performances were analyzed in the scalp-frequency domain using SPM12. Significant clusters of high-frequency (beta-band and gamma-band) activity were observed when higher-quality versus lower-quality improvisations were compared. Higher-quality improvisations were associated with predominantly posterior left-hemisphere activity; lower-quality improvisations were associated with right temporo-parietal and fronto-polar activity. However, after statistically controlling for experience (defined as the number of public performances previously given), performance quality was a function of right-hemisphere, largely right-frontal, activity. These results support the notion that superior creative production is associated with hypofrontality and right-hemisphere activity thereby supporting a dual-process model of creativity in which experience influences the balance between executive and associative processes. This study also highlights the idea that the functional neuroanatomy of creative production depends on whether creativity is defined in terms of the quality of products or the type of cognitive processes involved. • Neural and behavioral evidence for an expertise-dependent, dual-process model of creativity. • Performance quality/creativity a function of right-hemispheric activity. • Superior creative production is associated with hypofrontality and the inhibition of executive Type-2 processes. • Sophisticated EEG analysis (SPM12; surface-Laplacian transformations) and machine-learning (k-fold validation) techniques. • Collection of high-density EEG during live guitar improvisation. [ABSTRACT FROM AUTHOR]