Enhancing Working Memory Capacity in Persian Cochlear Implanted Children: A Clinical Trial Study

Document Type: Original


1 Department of Audiology, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran and Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

2 Department of Speech Therapy, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran and Rehabilitation Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

3 Department of Audiology, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.

4 Department of Otolaryngology, Shiraz University of Medical Sciences, Shiraz, Iran.

5 Fars Cochlear Implant Center, Shiraz University of Medical Sciences, Shiraz, Iran.

6 Department of Biostatistics, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.


Sensory deprivations such as hearing impairment that affect sensory input have a secondary impact on cognitive functions such as working memory (WM). WM capacity is an important cognitive component that processes language-related activities. Moreover, several studies have shown a deficit in WM in children with a cochlear implant (CI). We aimed to assess the performance of children with CIs in pre- and post-training sessions and compare their scores on a battery of WM tests to investigate the efficacy of a WM training program.
 Materials and Methods:
Twenty-five children aged 7–10 years with a CI participated in this study. To train their WM, a computer game was used. In order to examine auditory WM, a test battery including standardized digit span (forward and backward variations), non-word and sentence repetition (subtest of the Test of Language Development–Primary) were assessed in pre- and post-training test sessions at Shiraz Implant Center.
There were statistically significant differences between pre- and post-training test scores on all subtests. Test score differences were statistically significant for forward digit span (P=0.003), backward digit span (P=0.001), non-word repetition (P=0.001), and sentence repetition tasks (P=0.003) before and after training sessions.
Training may enhance WM capacity. With regards to the importance of WM in literacy and learning, it seems applying such intervention programs may be helpful in the rehabilitation of implanted children.


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