The DiSCoVeR trial – first look at patient training and their expectations regarding a new, innovative treatment

Introduction

The DiSCoVeR trial is a multi-site, double-blind, sham controlled, randomized controlled trial (RCT) investigating the feasibility and efficacy of an innovative, self-applied treatment approach for patients suffering from major depressive disorder (MDD). The treatment approach incorporates non-invasive brain stimulation, i.e. prefrontal transcranial direct current stimulation (tDCS), and a videogame designed to enhance emotional cognitive control. This treatment is aimed to be applied at home and monitored remotely.

Objectives

In this study we are looking at the first 10 single-site patients and comparing expected in person visits (according to the study protocol) versus actual in person visits as well as looking at the patients initial view of the therapy using the therapy evaluation form (CEQ) submitted after the 5th session.

Methods

Before continuing to self-administer the treatment at home patients undergo supervised training, during clinic visits, for up to 5 sessions. At the end of the 5th session, they are asked to fill out a therapy evaluation form (CEQ).

Results

Patients needed on average 2.3 in person training sessions before continuing the intervention remotely. Nine patients completed CEQ. Results show that on average patients thought that this course will be 4.78 (with probability 95% CI 4.74 to 4.82) points successful at raising their level of functioning and thought that their functioning will have increased on average by 37.8% (CI 37.2% to 38.4%) by the end of the study.

Conclusions

Patients needed less than half of planned in person training visits. Most patients felt like they will gain some improvement from this intervention.

Disclosure

No significant relationships.

Cognitive development: gaming your way out of dyslexia?

A recent study found that dyslexic children trained on action video games show significant improvements on basic measures of both attention and reading ability, suggesting future directions for the study of dyslexia intervention paradigms.

Learning, attentional control, and action video games

While humans have an incredible capacity to acquire new skills and alter their behavior as a result of experience, enhancements in performance are typically narrowly restricted to the parameters of the training environment, with little evidence of generalization to different, even seemingly highly related, tasks. Such specificity is a major obstacle for the development of many real-world training or rehabilitation paradigms, which necessarily seek to promote more general learning. In contrast to these typical findings, research over the past decade has shown that training on 'action video games' produces learning that transfers well beyond the training task. This has led to substantial interest among those interested in rehabilitation, for instance, after stroke or to treat amblyopia, or training for various precision-demanding jobs, for instance, endoscopic surgery or piloting unmanned aerial drones. Although the predominant focus of the field has been on outlining the breadth of possible action-game-related enhancements, recent work has concentrated on uncovering the mechanisms that underlie these changes, an important first step towards the goal of designing and using video games for more definite purposes. Game playing may not convey an immediate advantage on new tasks (increased performance from the very first trial), but rather the true effect of action video game playing may be to enhance the ability to learn new tasks. Such a mechanism may serve as a signature of training regimens that are likely to produce transfer of learning.

Neural bases of selective attention in action video game players

Over the past few years, the very act of playing action video games has been shown to enhance several different aspects of visual selective attention, yet little is known about the neural mechanisms that mediate such attentional benefits. A review of the aspects of attention enhanced in action game players suggests there are changes in the mechanisms that control attention allocation and its efficiency (Hubert-Wallander, Green, & Bavelier, 2010). The present study used brain imaging to test this hypothesis by comparing attentional network recruitment and distractor processing in action gamers versus non-gamers as attentional demands increased. Moving distractors were found to elicit lesser activation of the visual motion-sensitive area (MT/MST) in gamers as compared to non-gamers, suggestive of a better early filtering of irrelevant information in gamers. As expected, a fronto-parietal network of areas showed greater recruitment as attentional demands increased in non-gamers. In contrast, gamers barely engaged this network as attentional demands increased. This reduced activity in the fronto-parietal network that is hypothesized to control the flexible allocation of top-down attention is compatible with the proposal that action game players may allocate attentional resources more automatically, possibly allowing more efficient early filtering of irrelevant information.

The development of attention skills in action video game players

Previous research suggests that action video game play improves attentional resources, allowing gamers to better allocate their attention across both space and time. In order to further characterize the plastic changes resulting from playing these video games, we administered the Attentional Network Test (ANT) to action game players and non-playing controls aged between 7 and 22 years. By employing a mixture of cues and flankers, the ANT provides measures of how well attention is allocated to targets as a function of alerting and orienting cues, and to what extent observers are able to filter out the influence of task irrelevant information flanking those targets. The data suggest that action video game players of all ages have enhanced attentional skills that allow them to make faster correct responses to targets, and leaves additional processing resources that spill over to process distractors flanking the targets.

Exercising your brain: a review of human brain plasticity and training-induced learning

Human beings have an amazing capacity to learn new skills and adapt to new environments. However, several obstacles remain to be overcome in designing paradigms to broadly improve quality of life. Arguably, the most notable impediment to this goal is that learning tends to be quite specific to the trained regimen and does not transfer to even qualitatively similar tasks. This severely limits the potential benefits of learning to daily life. This review discusses training regimens that lead to the acquisition of new knowledge and strategies that can be used flexibly across a range of tasks and contexts. Possible characteristics of training regimens are proposed that may be responsible for augmented learning, including the manner in which task difficulty is progressed, the motivational state of the learner, and the type of feedback the training provides. When maximally implemented in rehabilitative paradigms, these characteristics may greatly increase the efficacy of training.

Encoding, rehearsal, and recall in signers and speakers: shared network but differential engagement

Short-term memory (STM), or the ability to hold verbal information in mind for a few seconds, is known to rely on the integrity of a frontoparietal network of areas. Here, we used functional magnetic resonance imaging to ask whether a similar network is engaged when verbal information is conveyed through a visuospatial language, American Sign Language, rather than speech. Deaf native signers and hearing native English speakers performed a verbal recall task, where they had to first encode a list of letters in memory, maintain it for a few seconds, and finally recall it in the order presented. The frontoparietal network described to mediate STM in speakers was also observed in signers, with its recruitment appearing independent of the modality of the language. This finding supports the view that signed and spoken STM rely on similar mechanisms. However, deaf signers and hearing speakers differentially engaged key structures of the frontoparietal network as the stages of STM unfold. In particular, deaf signers relied to a greater extent than hearing speakers on passive memory storage areas during encoding and maintenance, but on executive process areas during recall. This work opens new avenues for understanding similarities and differences in STM performance in signers and speakers.

Video games as a tool to train visual skills

PURPOSE

Adult brain plasticity, although possible, is often difficult to elicit. Training regimens in adults can produce specific improvements on the trained task without leading to general enhancements that would improve quality of life. This paper considers the case of playing action video games as a way to induce widespread enhancement in vision.

CONCLUSIONS

We review the range of visual skills altered by action video game playing as well as the game components important in promoting visual plasticity. Further, we discuss what these results might mean in terms of rehabilitation for different patient populations.

Action-video-game experience alters the spatial resolution of vision

Playing action video games enhances several different aspects of visual processing; however, the mechanisms underlying this improvement remain unclear. Here we show that playing action video games can alter fundamental characteristics of the visual system, such as the spatial resolution of visual processing across the visual field. To determine the spatial resolution of visual processing, we measured the smallest distance a distractor could be from a target without compromising target identification. This approach exploits the fact that visual processing is hindered as distractors are brought close to the target, a phenomenon known as crowding. Compared with nonplayers, action-video-game players could tolerate smaller target-distractor distances. Thus, the spatial resolution of visual processing is enhanced in this population. Critically, similar effects were observed in non-video-game players who were trained on an action video game; this result verifies a causative relationship between video-game play and augmented spatial resolution.

Enumeration versus multiple object tracking: the case of action video game players

Here, we demonstrate that action video game play enhances subjects' ability in two tasks thought to indicate the number of items that can be apprehended. Using an enumeration task, in which participants have to determine the number of quickly flashed squares, accuracy measures showed a near ceiling performance for low numerosities and a sharp drop in performance once a critical number of squares was reached. Importantly, this critical number was higher by about two items in video game players (VGPs) than in non-video game players (NVGPs). A following control study indicated that this improvement was not due to an enhanced ability to instantly apprehend the numerosity of the display, a process known as subitizing, but rather due to an enhancement in the slower more serial process of counting. To confirm that video game play facilitates the processing of multiple objects at once, we compared VGPs and NVGPs on the multiple object tracking task (MOT), which requires the allocation of attention to several items over time. VGPs were able to successfully track approximately two more items than NVGPs. Furthermore, NVGPs trained on an action video game established the causal effect of game playing in the enhanced performance on the two tasks. Together, these studies confirm the view that playing action video games enhances the number of objects that can be apprehended and suggest that this enhancement is mediated by changes in visual short-term memory skills.

Impact of early deafness and early exposure to sign language on the cerebral organization for motion processing

This functional magnetic resonance imaging study investigated the impact of early auditory deprivation and/or use of a visuospatial language [American sign language (ASL)] on the organization of neural systems important in visual motion processing by comparing hearing controls with deaf and hearing native signers. Participants monitored moving flowfields under different conditions of spatial and featural attention. Recruitment of the motion-selective area MT-MST in hearing controls was observed to be greater when attention was directed centrally and when the task was to detect motion features, confirming previous reports that the motion network is selectively modulated by different aspects of attention. More importantly, we observed marked differences in the recruitment of motion-related areas as a function of early experience. First, the lateralization of MT-MST was found to shift toward the left hemisphere in early signers, suggesting that early exposure to ASL leads to a greater reliance on the left MT-MST. Second, whereas the two hearing populations displayed more MT-MST activation under central than peripheral attention, the opposite pattern was observed in deaf signers, indicating enhanced recruitment of MT-MST during peripheral attention after early deafness. Third, deaf signers, but neither of the hearing populations, displayed increased activation of the posterior parietal cortex, supporting the view that parietal functions are modified after early auditory deprivation. Finally, only in deaf signers did attention to motion result in enhanced recruitment of the posterior superior temporal sulcus, establishing for the first time in humans that this polymodal area is modified after early sensory deprivation. Together these results highlight the functional and regional specificity of neuroplasticity in humans.

Visual attention to the periphery is enhanced in congenitally deaf individuals

We compared normally hearing individuals and congenitally deaf individuals as they monitored moving stimuli either in the periphery or in the center of the visual field. When participants monitored the peripheral visual field, greater recruitment (as measured by functional magnetic resonance imaging) of the motion-selective area MT/MST was observed in deaf than in hearing individuals, whereas the two groups were comparable when attending to the central visual field. This finding indicates an enhancement of visual attention to peripheral visual space in deaf individuals. Structural equation modeling was used to further characterize the nature of this plastic change in the deaf. The effective connectivity between MT/MST and the posterior parietal cortex was stronger in deaf than in hearing individuals during peripheral but not central attention. Thus, enhanced peripheral attention to moving stimuli in the deaf may be mediated by alterations of the connectivity between MT/MST and the parietal cortex, one of the primary centers for spatial representation and attention.

Positive and negative compatibility effects

This paper reports a series of four experiments that established a negative compatibility effect (NCE) by which compatible distractors led to slower and less accurate target performance than did incompatible ones (Experiment 1). This effect is interpreted as an early perceptual effect that delays the attribution of visual attention over the target location in the compatible condition. This view predicted that the NCE should be observed only when attention has to be selectively attributed to the target location. In Experiments 2 and 3, this prediction was tested by manipulating the perceptual load in the display. High perceptual load displays are known to require selective attention (Lavie, 1995). Accordingly, reliable NCEs were observed when high-load displays were used. In contrast, reduced NCEs were found in displays that did not require selective attention. Experiment 4 established that the manifestation of the NCE was influenced by low-level visual cues, such as brightness and contrast. Overall, these experiments indicated that the NCE can be understood as an early perceptual effect, which arises from a conflict between the cues that guide the distribution of attention when the task requires selective attention.

Hemispheric specialization for English and ASL: left invariance-right variability

Functional magnetic resonance imaging (fMRI) was used to compare the cerebral organization during sentence processing in English and in American sign language (ASL). Classical language areas within the left hemisphere were recruited by both English in native speakers and ASL in native signers. This suggests a bias of the left hemisphere to process natural languages independently of the modality through which language is perceived. Furthermore, in contrast to English, ASL strongly recruited right hemisphere structures. This was true irrespective of whether the native signers were deaf or hearing. Thus, the specific processing requirements of the language also in part determine the organization of the language systems of the brain.

Neural organization and plasticity of language

Powerful advances in neuroimaging techniques have added to and refined classical descriptions of the neurobiology of language in adults. Recent studies have employed these methodologies to study the nature and extent of plasticity of language-relevant aspects of cerebral organization in adults, in early and late bilinguals and in people who have acquired language through different modalities. Studies of children have documented dynamic shifts in cerebral organization over the course of language acquisition. Each of these different approaches has revealed constraints on the identity of the neural systems that mediate language; these studies have also described the marked and specific effects of language experience on the organization of these systems.

Cerebral organization for language in deaf and hearing subjects: biological constraints and effects of experience

Cerebral organization during sentence processing in English and in American Sign Language (ASL) was characterized by employing functional magnetic resonance imaging (fMRI) at 4 T. Effects of deafness, age of language acquisition, and bilingualism were assessed by comparing results from (i) normally hearing, monolingual, native speakers of English, (ii) congenitally, genetically deaf, native signers of ASL who learned English late and through the visual modality, and (iii) normally hearing bilinguals who were native signers of ASL and speakers of English. All groups, hearing and deaf, processing their native language, English or ASL, displayed strong and repeated activation within classical language areas of the left hemisphere. Deaf subjects reading English did not display activation in these regions. These results suggest that the early acquisition of a natural language is important in the expression of the strong bias for these areas to mediate language, independently of the form of the language. In addition, native signers, hearing and deaf, displayed extensive activation of homologous areas within the right hemisphere, indicating that the specific processing requirements of the language also in part determine the organization of the language systems of the brain.

Sentence Reading: A Functional MRI Study at 4 Tesla

In this study, changes in blood oxygenation and volume were monitored while monolingual right-handed subjects read English sentences. Our results confirm the role of the left peri-sylvian cortex in language processing. Interestingly, individual subject analyses reveal a pattern of activation characterized by several small, limited patches rather than a few large, anatomically well-circumscribed centers. Between-subject analyses confirm a lateralized pattern of activation and reveal active classical language areas including Broca's area, Wernicke's area, and the angular gyms. In addition they point to areas only more recently considered as language-relevant including the anterior portion of the superior temporal sulcus. This area has not been reliably observed in imaging studies of isolated word processing. This raises the hypothesis that activation in this area is dependent on processes specific to sentence reading.