The cognitive significance of resonating neurons in the cerebral cortex

Most neural fibers of the cerebral cortex engage in electric signaling, but one particular fiber, the apical dendrite of the pyramidal neuron, specializes in electric resonating. This dendrite extends upward from somas of pyramidal neurons, the most numerous neurons of the cortex. The apical dendrite is embedded in a recurrent corticothalamic circuit that induces surges of electric current to move repeatedly down the dendrite. Narrow bandwidths of surge frequency (resonating) enable cortical circuits to use specific carrier frequencies, which isolate the processing of those circuits from other circuits. Resonating greatly enhances the intensity and duration of electrical activity of a neuron over a narrow frequency range, which underlies attention in its various modes. Within the minicolumn, separation of the central resonating circuit from the surrounding signal processing network separates “having” subjective impressions from “thinking about” them. Resonating neurons in the insular cortex apparently underlie cognitive impressions of feelings.     

Object-centered representations support flexible exogenous visual attention across translation and reflection

Visual attention can be deployed to stimuli based on our willful, top-down goal (endogenous attention) or on their intrinsic saliency against the background (exogenous attention). Flexibility is thought to be a hallmark of endogenous attention, whereas decades of research show that exogenous attention is attracted to the retinotopic locations of the salient stimuli. However, to the extent that salient stimuli in the natural environment usually form specific spatial relations with the surrounding context and are dynamic, exogenous attention, to be adaptive, should embrace these structural regularities. Here we test a non-retinotopic, object-centered mechanism in exogenous attention, in which exogenous attention is dynamically attracted to a relative, object-centered location. Using a moving frame configuration, we presented two frames in succession, forming either apparent translational motion or in mirror reflection, with a completely uninformative, transient cue presented at one of the item locations in the first frame. Despite that the cue is presented in a spatially separate frame, in both translation and mirror reflection, behavioralperformance in visual search is enhanced when the target in the second frame appears at the same relative location as the cue location than at other locations. These results provide unambiguous evidence for non-retinotopic exogenous attention and further reveal an object-centered mechanism supporting flexible exogenous attention. Moreover, attentional generalization across mirror reflection may constitute an attentional correlate of perceptual generalization across lateral mirror images, supporting an adaptive, functional account of mirror images confusion.     

Gaze cueing as a function of perceived gaze direction

Previous studies have found that attention is automatically oriented in the direction of other people's gaze. This study directly investigated whether the perceiving gaze direction modulates the orienting of observers' attention. Gaze perception was manipulated by changing the face context (head orientation) of the gaze cue: the perceived gaze angle was increased (or decreased) when the head and gaze are congruent (or incongruent), while the local‐feature information of the eye region was preserved for all stimuli. The results showed that gaze‐cueing effects were enhanced when the perceived gaze direction was averted more toward left or right, and reduced when the perceived gaze direction was closer to direct gaze. The results suggest that gaze‐cueing effects are based on mechanisms specialized for gaze perception, and the magnitude of gaze‐cueing effects was probably a function of the perceived gaze direction.     

Reflection-Impulsivity in Mexican Children: Cross-Cultural Relationships

Urban Mexican children aged 5 (n = 23) and 9 (n = 87) years were given the Matching Familiar Figures Test (MFFT). The results indicate that the MFFT was a valid test of cognitive style for Mexican children. The younger children's MFFT performance was characterized as fast and inaccurate in relation to the older children's performance, which was slower and more accurate. Cross-cultural comparisons of Mexican MFFT scores with normative data from America, Japan, and Israel indicated that Mexican children were relatively impulsive in cognitive style in relation to children of other cultures. Potential factors contributing to these cross-cultural differences are discussed here.     

Investigating the Role of Instructional Focus in Incidental Pattern Learning

The authors used a novel dual-component training procedure that combined a serial reaction time task and an artificial grammar learning task to investigate the role of instructional focus in incidental pattern learning. In Experiment 1, participants either memorized letter strings as a primary task and reacted to the stimuli locations as a secondary task or vice versa. In Experiment 2, participants were given the same dual-component stimuli but performed only one of the two training tasks. Instructional focus affected the amount of learning and the likelihood of acquiring explicit knowledge of the underlying pattern. However, the effect of instructional focus varied for the different types of stimuli. These results are discussed in terms of the role of focused attention in incidental learning.     

Changes in Skin Potentials During the Psychogalvanic Reflex

Researchers have shown that working memory is related to a variety of high-level cognitive processes. However, the results of recent research have suggested that may be because of its role in attentional control. In the present experiment, the authors investigated that hypothesis by using an attentional interference task with musical stimuli. Listeners were asked to monitor one ear for either a clarinet or violin tone and to ignore any information in the other ear. On some of the trials, they heard only one tone and on other trials, either the same instrument in both ears or different instruments. Individual differences were measured in working memory and musical experience. The results showed more attentional interference in the different-instrument condition for participants with lower working memory scores, which suggested that working memory involves the ability to control attention to inhibit irrelevant information.     

Sampling Methods for Identifying Differences in Source Reliability

This study explored observer performance in using across-trial and within-trial variability information to weight sources based on reliability. Three trained observers performed a multi-element, visual signal-detection task under 3 block-type conditions: a fixed block condition and 2 random conditions. In the fixed block condition, the observers had both within- and across-trial variability information to identify differences in source reliability. The random conditions eliminated the across-trial information, leaving only within-trial variability information in 1 case and neither within- nor across-trial variability information in another case. There was a significant block-type effect. Observers could use differences in across-trial variability of individual sources to assign weights. Although there was a difference in the weights assigned to reliable and unreliable sources in the partial-random condition (in which within-trial variability information was available), only 1 participant showed a significant difference in the weight assignment relative to the full-random condition. Thus, altogether, observers were not very efficient at using within-trial variability to weight sources accordingly.     

A Question of Foot Dominance

It is suggested that the popular definition of foot dominance (i.e., the limb preferred to execute a manipulative or mobilizing action while the other [nondominant] foot provides stabilizing support, e.g., kicking a ball) be reconsidered in light of understanding the functional characteristics of footedness and selected theoretical explanations. Relevance to future research designs and assessment methodology is discussed.     

Children's Responses to Entry Failure: Attention Deployment Patterns and Self-Regulation Skills

In this study the authors investigated associations among children's observed responses to failure in an analogue entry situation, their attention deployment patterns, and skills and processes associated with self-regulation. Participants were 54 kindergarten and first-grade students who were either aggressive-rejected or low aggressive-popular based on peer nominations. Inhibitory control predicted the tendency to respond to entry failure by stopping and watching the group's activity. Baseline vagal tone and other-directed attention predicted children's tendency to change entry strategies after failure. Parent-rated attention skills moderated the relation between children's attention deployment patterns during the entry task and their responses to entry failure. Children who engaged in more other-directed attention were less likely to turn to solitary play after entry failure but only if they had high or moderate levels of attentional control. Other-directed attention was related to repeating previous entry bids without modification after entry failure but only when children had high levels of attention problems.     

Learning to Minimize Energy Costs and Maximize Mechanical Work in a Bimanual Coordination Task

The authors addressed the hypothesis that economy in motor coordination is a learning phenomenon realized by both reduced energy cost for a given workload and more external work at the same prepractice metabolic and attentional energy expenditure. "Self-optimization" of movement parameters has been proposed to reflect learned motor adaptations that minimize energy costs. Twelve men aged 22.3 ± 3.9 years practiced a 90° relative phase, upper limb, independent ergometer cycling task at 60 rpm, followed by a transfer test of unpracticed (45 and 75 rpm) and selfpaced cadences. Performance in all conditions was initially unstable, inaccurate, and relatively high in both metabolic and attentional energy costs. With practice, coordinative stability increased, more work was performed for the same metabolic and attentional costs, and the same work was done at a reduced energy cost. Selfpaced cycling was initially below the metabolically optimal, but following practice at 60 rpm was closer to optimal cadence. Given the many behavioral options of the motor system in meeting a variety of everyday movement task goals, optimal metabolic and attentional energy criteria may provide a solution to the problem of selecting the most adaptive coordination and control parameters.