Aging Associated Specificity in Training Visual Short-Term Memory

There are numerous data in existence, the computerized cognitive training programs (CCTP) maintain or improve the plasticity of the neural networks in the brain. It is known as well that CCTP reduces the probability of cognitive dysfunctions associated with aging. In the chapter, the age-associated specificity in the temporal dynamics of changes in the visuospatial short-term memory (VSWM, also called visuospatial working memory) is presented. VSWM has been analyzed as there are evidence for age-related decline in visuospatial memory associated with hippocampus atrophy in aging. Memory retrieval decline in older women in comparison with young women while computerized training at home is shown. The elderly achieving results which are comparable to the youngs are determined by significantly increased duration while performing the memory tasks. To reveal factors of the CCTP’s efficiency, age-related differences in the attention systems using the Attention Network Test were resolved. In the group of older women, VSWM efficiency is negatively related to the errors of incongruent information selection whereas in young women—to the reaction time while testing. Thus, the success of long-term systematic training of visuospatial memory in old age is strongly related to the high level of executive control.

The development of structural covariance networks during the transition from childhood to adolescence

Structural covariance conceptualizes how morphologic properties of brain regions are related to one another (across individuals). It can provide unique information to cortical structure (e.g., thickness) about the development of functionally meaningful networks. The current study investigated how structural covariance networks develop during the transition from childhood to adolescence, a period characterized by marked structural re-organization. Participants (N = 192; scans = 366) completed MRI assessments between 8.5 and 14.5 years of age. A sliding window approach was used to create “age-bins”, and structural covariance networks (based on cortical thickness) were created for each bin. Next, generalized additive models were used to characterize trajectories of age-related changes in network properties. Results revealed nonlinear trajectories with “peaks” in mean correlation and global density that are suggestive of a period of convergence in anatomical properties across the cortex during early adolescence, prior to regional specialization. “Hub” regions in sensorimotor cortices were present by late childhood, but the extent and strength of association cortices as “hubs” increased into mid-adolescence. Moreover, these regional changes were found to be related to rates of thinning across the cortex. In the context of neurocognitive networks, the frontoparietal, default mode, and attention systems exhibited age-related increases in within-network and between-network covariance. These regional and modular developmental patterns are consistent with continued refinement of socioemotional and other complex executive functions that are supported by higher-order cognitive networks during early adolescence.

An image-computable model of attention and texture segmentation

ABSTRACTAttention can facilitate or impair texture segmentation, altering whether objects are isolated from their surroundings in visual scenes. We simultaneously explain several empirical phenomena of texture segmentation and its attentional modulation with a single image-computable model. At the model’s core, segmentation relies on the interaction between sensory processing and attention, with different operating regimes for involuntary and voluntary attention systems. Model comparisons were used to identify computations critical for texture segmentation and attentional modulation. The model reproduced (i) the central performance drop, which is the parafoveal advantage for segmentation over the fovea, (ii) the peripheral improvements and central impairments induced by involuntary attention and (iii) the uniform improvements across eccentricity by voluntary attention. The proposed model reveals distinct functional roles for involuntary and voluntary attention and provides a generalizable quantitative framework for predicting the perceptual impact of attention across the visual field.

Modern vision of relationship between theta rhythm and the processes of attention

At present time conceptions of complex neurophysiological mechanisms underlying processes of attention are actively developing. In last few years, several researches revealed rhythmic character of processes of attention. Especially theta-rhythm is considered to be significant in organization of rhythmic interactions between brain zones, which take part in providing attention systems work. The aim of the work – to analyze and summarize modern date about role of theta-rhythm in providing basic processes of attention. The report presents modern data about role of theta-rhythm in processes of attention. Specific features of attention systems are discussed. Thrifold model of attention, developed by Steven E. Petersen and Michael I. Posner is reviewed in detail. Moreover, evidences of rhythmic character of processes of attention are summarized and leading part of theta-activity in providing these processes is demonstrated. We also discuss the investigations by Randolph F. Helfrich and Ian C. Fiebelkorn et al. which stated that the quantization of processes of attention with theta-frequency as a general principle of brain structures activity. Dependence of frequency characteristics of cortex zones of human brain from number of objects of attention is discussed. There is also an analysis of theta-band’s ability to modulate biopotentials of higher frequency. Special attention is paid to the researches focused on theta-gamma coupling. The influence of theta-rhythm phase on gamma-rhythm amplitude in phase-amplitude coupling of theta- and gamma-band is analyzed. Theta-rhythm is considered to be one of the rhythmic components that regulate complex mental functions such as attention, memory and consciousness. Obviously, there is a lack of an exact understanding of the role for every band in mental functions regulation; therefore, more investigations in this field are required. However, several data about the role of theta-band in mental functions was collected. A complex of systems with different physiological and neurochemical basis provides attention. It was demonstrated that attention - is a rhythmical process in which theta-band is a crucial part. Theta-rhythm provides synchronization and joint activity of distant brain structures. Moreover, theta-rhythm modulates high-frequent bands. Theta- gamma-band coupling is supposed to be important for attention. Such cooperation is considered to be an evidence of cortical and subcortical zones and provides coordination of analyzing systems of different level. It is suggested that different phases of theta-band may provide retention/switching of attention or determine information flow. As a summary of review of literary sources, there is a conclusion about high significance of this frequency range in different attention systems functioning.

Anterior insula and inferior frontal gyrus: where ventral and dorsal visual attention systems meet

The clinical link between spatial and non-spatial attentional aspects in patients with hemispatial neglect is well known; in particular, an increase in alerting can transitorily help to allocate attention towards the contralesional side. In models of attention, this phenomenon is postulated to rely on an interaction between ventral and dorsal cortical networks, subtending non-spatial and spatial attentional aspects, respectively. However, the exact neural underpinnings of the interaction between these two networks are still poorly understood. In the present study, we included 80 right-hemispheric patients with subacute stroke (50% women; age range: 24–96), 33 with and 47 without neglect, as assessed by paper–pencil cancellation tests. The patients performed a computerized task in which they were asked to respond as quickly as possible by button-press to central targets, which were either preceded or not preceded by non-spatial, auditory warning tones. Reaction times in the two different conditions were measured. In neglect patients, a warning tone, enhancing activity within the ventral attentional ‘alerting’ network, could boost the reaction (in terms of shorter reaction times) of the dorsal attentional network to a visual stimulus up to the level of patients without neglect. Critically, using voxel-based lesion-symptom mapping analyses, we show that this effect significantly depends on the integrity of the right anterior insula and adjacent inferior frontal gyrus, i.e., right-hemispheric patients with lesions involving these areas were significantly less likely to show shorter reaction times when a warning tone was presented prior to visual target appearance. We propose that the right anterior insula and inferior frontal gyrus are a critical hub through which the ventral attentional network can ‘alert’ and increase the efficiency of the activity of the dorsal attentional network.

Autistic traits are associated with the functional connectivity of between—but not within—attention systems in the general population

Background Previous studies have demonstrated that individuals with autism spectrum disorder (ASD) exhibit dysfunction in the three attention systems (i.e., alerting, orienting, and executive control) as well as atypical relationships among these systems. Additionally, other studies have reported that individuals with subclinical but high levels of autistic traits show similar attentional tendencies to those observed in ASD. Based on these findings, it was hypothesized that autistic traits would affect the functions and relationships of the three attention systems in a general population. Resting-state functional magnetic resonance imaging (fMRI) was performed in 119 healthy adults to investigate relationships between autistic traits and within- and between-system functional connectivity (FC) among the three attention systems. Twenty-six regions of interest that were defined as components of the three attention systems by a previous task-based fMRI study were examined in terms of within- and between-system FC. We assessed autistic traits using the Autism-Spectrum Quotient. Results Correlational analyses revealed that autistic traits were significantly correlated with between-system FC, but not with within-system FC. Conclusions Our results imply that a high autistic trait level, even when subclinical, is associated with the way the three attention systems interact.

Autistic traits are associated with the functional connectivity of between—but not within—attention systems in the general population

Background: Previous studies have demonstrated that individuals with autism spectrum disorder (ASD) exhibit dysfunction in the three attention systems (i.e., alerting, orienting, and executive control) as well as atypical relationships among these systems. Additionally, other studies have reported that individuals with subclinical but high levels of autistic traits show similar attentional tendencies to those observed in ASD. Based on these findings, it was hypothesized that autistic traits would affect the functions and relationships of the three attention systems in a general population. Resting-state functional magnetic resonance imaging (fMRI) was performed in 119 healthy adults to investigate relationships between autistic traits and within- and between-system functional connectivity (FC) among the three attention systems. Twenty-six regions of interest that were defined as components of the three attention systems by a previous task-based fMRI study were examined in terms of within- and between-system FC. We assessed autistic traits using the Autism-Spectrum Quotient.Results: Correlational analyses revealed that autistic traits were significantly correlated with between-system FC, but not with within-system FC.Conclusions: Our results imply that a high autistic trait level, even when subclinical, is associated with the way the three attention systems interact.

Autistic traits are associated with the functional connectivity of between—but not within—attention systems in the general population

Background: Previous studies have demonstrated that individuals with autism spectrum disorder (ASD) exhibit dysfunction in the three attention systems (i.e., alerting, orienting, and executive control) as well as atypical relationships among these systems. Additionally, other studies have reported that individuals with subclinical but high levels of autistic traits show similar attentional tendencies to those observed in ASD. Based on these findings, it was hypothesized that autistic traits would affect the functions and relationships of the three attention systems in a general population. Resting-state functional magnetic resonance imaging (fMRI) was performed in 119 healthy adults to investigate relationships between autistic traits and within- and between-system functional connectivity (FC) among the three attention systems. Twenty-six regions of interest that were defined as components of the three attention systems by a previous task-based fMRI study were examined in terms of within- and between-system FC. We assessed autistic traits using the Autism-Spectrum Quotient.Results: Correlational analyses revealed that autistic traits were significantly correlated with between-system FC, but not with within-system FC. Conclusions: Our results imply that a high autistic trait level, even when subclinical, is associated with the way the three attention systems interact.

Autistic Traits Are Associated With the Functional Connectivity of Between- but Not Within-attention Systems in the General Population

Background: Previous studies have demonstrated that individuals with autism spectrum disorder (ASD) exhibit dysfunction in the three attention systems (i.e., Alerting, Orienting, and Executive control) as well as atypical relationships among these systems. Additionally, other studies have reported that individuals with subclinical but high levels of autistic traits show similar attentional tendencies as those observed in ASD. Based on these findings, it was hypothesized that autistic traits would affect the functions and relationships of the three attention systems in a general population. Resting-state functional magnetic resonance imaging (fMRI) was performed in 119 healthy adults to investigate relationships between autistic traits and within- and between-system functional connectivity (FC) among the three attention systems. Twenty-six regions of interest that were defined as components of the three attention systems by a previous task-based fMRI study were examined in terms of within-and between-system FC. Autistic traits were assessed using the Autism-Spectrum Quotient.Result: Correlational analyses revealed significant correlations between autistic traits and between-system FC but not within-system FC. Conclusions: Together with findings of previous studies, these results suggest that high level of autistic traits, even if it is subclinical, affect relationships among the three systems and could possibly induce changes in the efficiency of attention.