Reducing Cognitive Deficits after Stroke through Computerized Progressive Attentional Training (CPAT): A Pilot Study

Special Article - Stroke Rehabilitation

Phys Med Rehabil Int. 2015; 2(7): 1058.

Reducing Cognitive Deficits after Stroke through Computerized Progressive Attentional Training (CPAT): A Pilot Study

Sampanis DS¹, Mevorach C¹, Shalev L², Mohammed S¹ and Humphreys GW³*

¹School of Psychology, University of Birmingham, England

²School of Education and School of Neuroscience, Tel Aviv University, Israel

³Department of Experimental Psychology, University of Oxford, England

*Corresponding author: Glyn W Humphreys, Department of Experimental Psychology, University of Oxford, England

Received: March 10, 2015; Accepted: September 09, 2015; Published: September 11, 2015


Background and Purpose: Cognitive deficits following stroke are common and are associated with poor rehabilitation outcome. Computerized Progressive Attentional Training (CPAT) has been tested and found effective in children with Attention Deficit/Hyperactivity Disorder (ADHD) and there is evidence also for similar training effects on healthy older adults (Anguera et al., 2013). This pilot trial explored the potential effectiveness of CPAT for improving cognition in stroke survivors with cognitive deficits within 2 months of their stroke.

Methods: Eight sub acute stroke participants underwent the CPAT protocol for 10 sessions during a period of two weeks and were compared with controls (who did not receive training) on both attention tasks (eight healthy controls) and general cognitive assessments (eight other sub acute patients). Attention was assessed before and after training using four lab-based attention tasks while cognitive impairment was assessed using the Birmingham Cognitive Screen (BCoS).

Results: The CPAT intervention resulted in improvements on both attention functions (specifically sustained attention) and non-attention functions (e.g., language, memory, number skills and praxis). These improvements could not be simply attributed to the passage of time or repetition of the test (as evident from healthy and the neuropsychological control group performance).

Conclusion: While the small sample size and the pilot nature of the study should be taken into account, the results indicate that CPAT is potentially an effective and valuable instrument that can be applied to help ameliorate attentional deficits following stroke.

Keywords: Attention; Stroke; Rehabilitation; Neuropsychology


Stroke is recognized worldwide as one of the major causes of disability [1]. Cognitive deficits following stroke are common. Recently, Humphreys et al. [2] reported that 70% of stroke patients tested on the Birmingham Cognitive Screen (BCoS) showed impaired cognitive functions. These impairments are also important predictors of outcome, and may lead to long term disability with significant impact on daily activities and independence of stroke survivors [3]. Post stroke attention deficits may even have a dramatic impact on functional recovery and are responsible for poor attendance during rehabilitation [4]. Cognitive and attentional problems in stroke often have impact on behaviour and can lead to chronic depression [5].

Given the high prevalence of stroke and its impact on cognitive and attentional aspects of daily living and functioning, considerable effort has been allocated to the development of various interventions that could ameliorate cognitive deficits following stroke [6]. Previous studies into the effects of attentional training have indicated positive outcome not only on attention but also on other domains of cognition (speed of processing, attention/vigilance, working memory, verbal learning and memory, visual learning and memory, and reasoning and problem solving - 7) and on everyday functional skills [8-10].

Stimulated by research showing that playing action video games can improve perceptual and attentional performance in young normal participants [11,12], a substantial number of attempts have now been made to use computer-based training to improve cognition in individuals showing some aspects of cognitive decline. This has included research on normal healthy ageing populations [13], patients with mild cognitive impairment [14], Alzheimer’s patients [15], and individuals with multiple sclerosis [16], acquired brain injury [17] and stroke survivors [18]. The results are mixed. In many of the studies training has produced benefits on the trained cognitive functions (e.g., improvements in working memory after working memory training; 13, 17]), but very often there have been failures to generalise improvements to non-trained functions [13,19]. In a recent Cochrane review of cognitive training of patients following stroke or other non-progressive forms of acquired brain damage, Chung et al. [20] concluded that there was insufficient high quality evidence for training having a benefit. Few studies used training tasks specifically designed to address critical cognitive processes, and few were designed with appropriate controls to measure effects of repeat testing and time. The authors highlight the need for high quality research which provides a fine-grained test of whether targeted cognitive training can improve cognition in neurological populations, whether training generalizes, and whether training effects supersede improvements produced by recovery through time and engagement in other ongoing activities.

One approach to enhance generalizability of computerised training is to follow early intervention studies [9] and to target cognitive processes that in themselves may sub-serve other cognitive processes. Aspects of attention are known to be important for a variety of cognitive processes and have been shown to produce generalised improvement [9, 21]. For instance, if there is poor sustained attention (the ability to keep attention ‘on task’ throughout a long period of time) or impairment in exerting executive control over processing then patients may show increased visual neglect and increased problems in language [22, 23]. It follows that computerised attention training of such processes (sustained attention, executive control) may yield generalised effects for stroke patients. Recently, Shalev et al. [21] used a Computerised Progressive Attention Training (CPAT) in a group of children with ADHD. The CPAT included aspects of sustained, executive and selective attention training. These authors reported improvements in the experimental group that transferred to a variety of non-trained tests such as maths, word copying as well as behavioural symptoms.

In stroke, problems in executive functions (task switching and inhibiting irrelevant stimuli and responses) and in sustained attention are common in occurrence [2] and potentially critical to a number of other cognitive domains. Thus the targeting of executive functions and sustained attention may be beneficial to induce generalized improvements after training in stroke patients too. To test this we employed the CPAT program developed by Shalev et al. [21] in a group of sub-acute stroke patients. We had patients train with three CPAT tasks, each of which was separately challenging. The tasks covered sustained attention, selective attention and executive control. Importantly, all of the tasks had progressive levels of difficulty which could be tuned to the abilities of individual patients, all used engaging ‘game-like’ displays (see Figure 1), and all generated easyto- understand graphical feedback to help motivate patients (see 21 for the use of CPAT in individuals with ADHD). In order to evaluate the outcome of computerised attention training and its potential generalization to other cognitive domains we measured performance before and after training (and in control groups) in a set of attention tasks as well as the patients’ cognitive abilities using the BCoS test battery (which examines a number of different aspects of cognition).