Decreased load on general motor preparation and visual-working memory while preparing familiar as compared to unfamiliar movement sequences

Learning movement sequences is thought to develop from an initial controlled attentive phase to a more automatic inattentive phase. Furthermore, execution of sequences becomes faster with practice, which may result from changes at a general motor processing level rather than at an effector specific motor processing level. In the current study, we examined whether these changes are already present during preparation. Fixed series of six keypresses, either familiar or unfamiliar, had to be prepared and executed/withheld after a go/nogo signal. Reaction time results confirmed that familiar sequences were executed faster than unfamiliar sequences. Results derived from the electroencephalogram showed a decreased demand on general motor preparation and visual-working memory before familiar sequences as compared to unfamiliar sequences. We propose that with familiar sequences the presetting segments of responses is less demanding than with unfamiliar sequences, as familiar sequences can be regarded as less complex than unfamiliar sequences. Finally, the decreasing demand on visual-working memory before familiar sequences suggests that sequence learning indeed develops from an attentive to an automatic phase.     

Brain networks associated with sublexical properties of Chinese characters

Cognitive models of reading all assume some division of labor among processing pathways in mapping among print, sound and meaning. Many studies of the neural basis of reading have used task manipulations such as rhyme or synonym judgment to tap these processes independently. Here we take advantage of specific properties of the Chinese writing system to test how differential availability of sublexical information about sound and meaning, as well as the orthographic structure of characters, pseudo-characters and “artificial” control stimuli influence brain activation in the context of the same one-back task. Analyses combine a data-driven approach that identifies temporally coherent patterns of activity over the course of the entire experiment with hypothesis-testing based on the correlation of these patterns with predictors for different stimulus classes. The results reveal a large network of task-related activity. Both the extent of this network and activity in regions commonly observed in studies of Chinese reading are apparently related to task difficulty. Other regions, including temporo-parietal cortex, were sensitive to particular sublexical functional units in mapping among print, sound, and meaning.     

Physical Attractiveness and Candidate Evaluation: A Model of Correction

Voters typically evaluate an attractive candidate more favorably than an (otherwise equivalent) unattractive candidate. However, some voters “correct” for the biasing influence of physical appearance. This reduces, eliminates, or even reverses the physical attractiveness effect. Correction occurs when political experts evaluate a political candidate under nondistracting conditions. Under these “high cognitive capacity” conditions, voters primarily correct for physical unattractiveness. However, correction fails to occur when voters possess low levels of expertise or are distracted. Thus, in most circumstances, attractive candidates are evaluated more favorably than unattractive candidates. Two experiments provide support for this model of appearance‐based candidate evaluation.     

Differential prefrontal–temporal neural correlates of semantic processing in children

This study used functional magnetic resonance imaging (fMRI) to examine brain–behavior correlations in a group of 16 children (9- to 12-year-olds). Activation was measured during a semantic judgment task presented in either the visual or auditory modality that required the individual to determine whether a final word was related in meaning to one of two previous words (e.g., found–tank–lost). The main finding was that higher performers (i.e., accuracy) were associated with more activation in posterior representational systems including the inferior and middle temporal gyri, whereas lower performers were associated with more activation in anterior regions including the inferior and middle frontal gyri. This pattern of results was interpreted as reflecting an elaborated semantic representational system in temporal areas for the high accuracy performers that allowed them to efficiently and accurately make meaning based judgments. The low accuracy performers may have an inaccurate or weakly interconnected semantic system that results in greater use of frontal areas in a feature selection process.     

Positive mood broadens visual attention to positive stimuli

In an attempt to investigate the impact of positive emotions on visual attention within the context of Fredrickson’s (1998) broaden-and-build model, eye tracking was used in two studies to measure visual attentional preferences of college students (n=58, n=26) to emotional pictures. Half of each sample experienced induced positive mood immediately before viewing slides of three similarly-valenced images, in varying central-peripheral arrays. Attentional breadth was determined by measuring the percentage viewing time to peripheral images as well as by the number of visual saccades participants made per slide. Consistent with Fredrickson’s theory, the first study showed that individuals induced into positive mood fixated more on peripheral stimuli than did control participants; however, this only held true for highly-valenced positive stimuli. Participants under induced positive mood also made more frequent saccades for slides of neutral and positive valence. A second study showed that these effects were not simply due to differences in emotional arousal between stimuli. Selective attentional broadening to positive stimuli may act both to facilitate later building of resources as well as to maintain current positive affective states.     

汉语单音节词汇产生中的激活反馈

采取图画-词汇干扰实验范式,探索汉语词汇产生中词条选择和音韵编码两个阶段之间是否存在激活的反馈。实验一探索的是字形激活能否反馈至语义层产生语义激活,结果发现,与无关条件相比,目标图画(如“锯”)的字形中介(“镇”)的语义相关字(“村”)条件显著地延长了图画命名的时间。这表明在汉语词汇产生过程中,字形层的激活能反馈至语义层。实验二探索的是语音激活能否反馈至语义层产生语义激活,结果发现,与无关条件相比,目标图画(“梨”)的语音中介(“厘”)的语义相关字(“毫”)条件并未显著地影响图画命名的时间。这表明语音层的激活不能反馈至语义层,或者反馈回的激活太微弱不能影响图画命名过程。实验一和二的结果更倾向于支持词汇产生中词条选择和音韵编码两个阶段独立的观点。     

Increased visual interest and affective responses to impossible figures in early infancy

This research evaluated infants’ facial expressions as they viewed pictures of possible and impossible objects on a TV screen. Previous studies in our lab demonstrated that four-month-old infants looked longer at the impossible figures and fixated to a greater extent within the problematic region of the impossible shape, suggesting they were sensitive to novel or unusual object geometry. Our work takes studies of looking time data a step further, determining if increased looking co-occurs with facial expressions associated with increased visual interest and curiosity, or even puzzlement and surprise. We predicted that infants would display more facial expressions consistent with either “interest” or “surprise” when viewing the impossible objects relative to possible ones, which would provide further evidence of increased perceptual processing due to incompatible spatial information. Our results showed that the impossible cubes evoked both longer looking times and more reactive expressions in the majority of infants. Specifically, the data revealed significantly greater frequency of raised eyebrows, widened eyes and returns to looking when viewing impossible figures with the most robust effects occurring after a period of habituation. The pattern of facial expressions were consistent with the “interest” family of facial expressions and appears to reflect infants’ ability to perceive systematic differences between matched pairs of possible and impossible objects as well as recognize novel geometry found in impossible objects. Therefore, as young infants are beginning to register perceptual discrepancies in visual displays, their facial expressions may reflect heightened attention and increased information processing associated with identifying irreconcilable contours in line drawings of objects. This work further clarifies the ongoing formation and development of early mental representations of coherent 3D objects.     

Probing communication-induced memory biases in preverbal infants: Two replication attempts of Yoon,Johnson and Csibra (2008)

In a seminal study, Yoon, Johnson and Csibra [PNAS, 105, 36 (2008)] showed that nine-month-old infants retained qualitatively different information about novel objects in communicative and non-communicative contexts. In a communicative context, the infants encoded the identity of novel objects at the expense of encoding their location, which was preferentially retained in non-communicative contexts. This result had not yet been replicated. Here we attempted two replications, while also including a measure of eye-tracking to obtain more detail of infants’ attention allocation during stimulus presentation. Experiment 1 was designed following the methods described in the original paper. After discussion with one of the original authors, some key changes were made to the methodology in Experiment 2. Neither experiment replicated the results of the original study, with Bayes Factor Analysis suggesting moderate support for the null hypothesis. Both experiments found differential attention allocation in communicative and non-communicative contexts, with more looking to the face in communicative than non-communicative contexts, and more looking to the hand in non-communicative than communicative contexts. High and low level accounts of these attentional differences are discussed.     

Visual load and variability of muscle activation: Effects on reactive driving of older adults

BackgroundThe functional significance of the increase in motor output variability with increased visual information processing in older adults remains unclear. Here, we test the hypothesis that increased visual information processing increases muscle activation variability in older adults and impairs their ability to react as fast and as precisely as young adults during a simulated reactive driving task.MethodsFourteen young and sixteen older adults performed a reactive driving simulation task that required responding to unexpected brake lights of the car ahead during a simple reaction time task (low visual information processing condition) and a choice reaction time task with “no go” trials condition (high visual information processing condition). We quantified the following: 1) reactive driving performance – combination of premotor response time, motor response time, and brake force error; 2) motor output variability – brake impulse variability; 3) muscle activation variability – variability in the tibialis anterior (TA) muscle activity.ResultsThe increase in information processing exacerbated the impaired reactive driving performance in older adults. The best predictor of this impairment was the increase in brake force error. The impaired reactive driving performance was related to brake impulse variability and variability in the TA activity.ConclusionsThis study provides novel evidence that increased information processing increases muscle activation variability in older adults with detrimental consequences to their ability to perform a simulated reactive driving task.     

THE COLLAPSE OF OLIGARCHIC CAPITALISM AND THE RISE OF REGENERATIVE LEARNING: HOW THE SCIENCE OF ENERGY SYSTEMS CLARIFIES WHAT’S HAPPENING TODAY AND WHAT COMES NEXT

We live in a head-spinning, gut-wrenching time of multiplying crises. At home we face outsourced jobs, crumbling cities, underpaid teachers, unaffordable healthcare, endless wars, political corruption, a co-opted corporate media, skyrocketing inequality, and public “austerity” measures whose main purpose is to make tax-breaks for the rich more affordable. Working-class stagnation is producing widespread anxiety, mounting debt, and “despair deaths” from opioid abuse. Fear is fueling populist outrage, along with extremism, authoritarianism, and the conditions for a fascist takeover. Meanwhile, climate change poses an existential threat to humanity itself. All of these calamities spring from the same root cause: an oligarchic capitalism that puts short-term profit for owners over people and planet. While this system seems immutable, upheavals from Occupy Wall Street to the rise of right-wing populism signal a backlash to a political–economic establishment that treats people and planet as resources to be pillaged and expenses to be minimized. Its failures have also been driving the development of new possibilities in the form of more systemic approaches. Still, while systems thinking has improved approaches in fields from agriculture to medicine, so far none of these reforms have been able to channel public frustration into true transformation because none addresses the root problem: oligarchy. The science of systemic vitality we need is also being born, but so far, its findings are diffuse. This article shows how the science of energy systems can galvanize today’s economic reformation by articulating the common sense rules and rigorous measures of systemic vitality, while anchoring them in an evidence-based vision of humanity as a collaborative learning species. The result is a practical path to building systemic socioeconomic vitality by revitalizing human networks, energizing collective learning, and clarifying why oligarchic capitalism is a distortion of our original democratic free-enterprise dream, which is now careening toward collapse.