Background: Working memory is an executive function that plays an important role in many aspects of daily life, and its impairment in patients with attention-deficit/hyperactivity disorder (ADHD) affects quality of life. The dorsolateral prefrontal cortex (DLPFC) has been a good target site for transcranial direct current stimulation (tDCS) due to its intense involvement in working memory. In our 2018 study, tDCS improved visual-verbal working memory in healthy subjects. Objective: This study examines the effects of tDCS on ADHD patients, particularly on verbal working memory. Methods: We conducted an experiment involving verbal working memory of two modalities, visual and auditory, and a sustained attention task that could affect working memory in 9 ADHD patients. Active or sham tDCS was applied to the left DLPFC in a single-blind crossover design. Results: tDCS significantly improved the accuracy of visual-verbal working memory. In contrast, tDCS did not affect auditory-verbal working memory and sustained attention. Conclusion: tDCS to the left DLPFC improved visual-verbal working memory in ADHD patients, with important implications for potential ADHD treatments.
References
[1]
Dedoncker, J., Brunoni, A.R., Baeken, C. and Vanderhasselt, M. (2016) A Systematic Review and Meta-Analysis of the Effects of Transcranial Direct Current Stimulation (tDCS) over the Dorsolateral Prefrontal Cortex in Healthy and Neuropsychiatric Samples: Influence of Stimulation Parameters. Brain Stimulation, 9, 501-517. https://doi.org/10.1016/j.brs.2016.04.006
[2]
Kuo, H., Bikson, M., Datta, A., Minhas, P., Paulus, W., Kuo, M., et al. (2013) Comparing Cortical Plasticity Induced by Conventional and High-Definition 4 × 1 Ring tDCS: A Neurophysiological Study. Brain Stimulation, 6, 644-648. https://doi.org/10.1016/j.brs.2012.09.010
[3]
Naka, M., Matsuzawa, D., Ishii, D., Hamada, H., Uchida, T., Sugita, K., et al. (2018) Differential Effects of High-Definition Transcranial Direct Current Stimulation on Verbal Working Memory Performance According to Sensory Modality. Neuroscience Letters, 687, 131-136. https://doi.org/10.1016/j.neulet.2018.09.047
[4]
Ruf, S.P., Fallgatter, A.J. and Plewnia, C. (2017) Augmentation of Working Memory Training by Transcranial Direct Current Stimulation (tDCS). Scientific Reports, 7, Article No. 876. https://doi.org/10.1038/s41598-017-01055-1
[5]
Mukherjee, P., Hartanto, T., Iosif, A., Dixon, J.F., Hinshaw, S.P., Pakyurek, M., et al. (2021) Neural Basis of Working Memory in ADHD: Load versus Complexity. NeuroImage: Clinical, 30, Article ID: 102662. https://doi.org/10.1016/j.nicl.2021.102662
[6]
Adler, L.A., Spencer, T., Faraone, S.V., Kessler, R.C., Howes, M.J., Biederman, J., et al. (2006) Validity of Pilot Adult ADHD Self-Report Scale (ASRS) to Rate Adult ADHD Symptoms. Annals of Clinical Psychiatry, 18, 145-148. https://doi.org/10.1080/10401230600801077
[7]
Fregni, F., Boggio, P.S., Nitsche, M., Bermpohl, F., Antal, A., Feredoes, E., et al. (2005) Anodal Transcranial Direct Current Stimulation of Prefrontal Cortex Enhances Working Memory. Experimental Brain Research, 166, 23-30. https://doi.org/10.1007/s00221-005-2334-6
[8]
Zhang, J. and Mueller, S.T. (2005) A Note on ROC Analysis and Non-Parametric Estimate of Sensitivity. Psychometrika, 70, 203-212. https://doi.org/10.1007/s11336-003-1119-8
[9]
Nelson, J.T., McKinley, R.A., Golob, E.J., Warm, J.S. and Parasuraman, R. (2014) Enhancing Vigilance in Operators with Prefrontal Cortex Transcranial Direct Current Stimulation (tDCS). NeuroImage, 85, 909-917. https://doi.org/10.1016/j.neuroimage.2012.11.061
Bush, G. (2009) Attention-Deficit/Hyperactivity Disorder and Attention Networks. Neuropsychopharmacology, 35, 278-300. https://doi.org/10.1038/npp.2009.120
[12]
Ko, C., Yen, J., Yen, C., Chen, C., Lin, W., Wang, P., et al. (2013) Brain Activation Deficit in Increased-Load Working Memory Tasks among Adults with ADHD Using fMRI. European Archives of Psychiatry and Clinical Neuroscience, 263, 561-573. https://doi.org/10.1007/s00406-013-0407-2
[13]
Sheridan, M.A., Hinshaw, S. and D’Esposito, M. (2010) Stimulant Medication and Prefrontal Functional Connectivity during Working Memory in ADHD. Journal of Attention Disorders, 14, 69-78. https://doi.org/10.1177/1087054709347444
[14]
Rodriguez-Jimenez, R., Avila, C., Garcia-Navarro, C., Bagney, A., Aragon, A.M.D., Ventura-Campos, N., et al. (2009) Differential Dorsolateral Prefrontal Cortex Activation during a Verbal N-Back Task According to Sensory Modality. Behavioural Brain Research, 205, 299-302. https://doi.org/10.1016/j.bbr.2009.08.022
[15]
Crottaz-Herbette, S., Anagnoson, R.T. and Menon, V. (2004) Modality Effects in Verbal Working Memory: Differential Prefrontal and Parietal Responses to Auditory and Visual Stimuli. NeuroImage, 21, 340-351. https://doi.org/10.1016/j.neuroimage.2003.09.019
[16]
Blomberg, R., Johansson Capusan, A., Signoret, C., Danielsson, H. and Rönnberg, J. (2021) The Effects of Working Memory Load on Auditory Distraction in Adults with Attention Deficit Hyperactivity Disorder. Frontiers in Human Neuroscience, 15, Article ID: 771711. https://doi.org/10.3389/fnhum.2021.771711
[17]
Ghanizadeh, A. (2011) Sensory Processing Problems in Children with ADHD, a Systematic Review. Psychiatry Investigation, 8, 89-94. https://doi.org/10.4306/pi.2011.8.2.89
[18]
McFadden, J.L., Borckardt, J.J., George, M.S. and Beam, W. (2011) Reducing Procedural Pain and Discomfort Associated with Transcranial Direct Current Stimulation. Brain Stimulation, 4, 38-42. https://doi.org/10.1016/j.brs.2010.05.002
[19]
Bush, G., Holmes, J., Shin, L.M., Surman, C., Makris, N., Mick, E., et al. (2013) Atomoxetine Increases Fronto-Parietal Functional MRI Activation in Attention-Deficit/Hyperactivity Disorder: A Pilot Study. Psychiatry Research: Neuroimaging, 211, 88-91. https://doi.org/10.1016/j.pscychresns.2012.09.004
[20]
Wong, H.C. and Zaman, R. (2019) Neurostimulation in Treating ADHD. Psychiatria Danubina, 31, 265-275.
[21]
Soltaninejad, Z., Nejati, V. and Ekhtiari, H. (2015) Effect of Anodal and Cathodal Transcranial Direct Current Stimulation on DLPFC on Modulation of Inhibitory Control in ADHD. Journal of Attention Disorders, 23, 325-332. https://doi.org/10.1177/1087054715618792
[22]
Jacoby, N. and Lavidor, M. (2018) Null tDCS Effects in a Sustained Attention Task: The Modulating Role of Learning. Frontiers in Psychology, 9, Article No. 476. https://doi.org/10.3389/fpsyg.2018.00476
[23]
Soff, C., Sotnikova, A., Christiansen, H., Becker, K. and Siniatchkin, M. (2016) Transcranial Direct Current Stimulation Improves Clinical Symptoms in Adolescents with Attention Deficit Hyperactivity Disorder. Journal of Neural Transmission, 124, 133-144. https://doi.org/10.1007/s00702-016-1646-y
[24]
Cachoeira, C.T., Leffa, D.T., Mittelstadt, S.D., Mendes, L.S.T., Brunoni, A.R., Pinto, J.V., et al. (2017) Positive Effects of Transcranial Direct Current Stimulation in Adult Patients with Attention-Deficit/Hyperactivity Disorder a Pilot Randomized Controlled Study. Psychiatry Research, 247, 28-32. https://doi.org/10.1016/j.psychres.2016.11.009
[25]
Breitling, C., Zaehle, T., Dannhauer, M., Bonath, B., Tegelbeckers, J., Flechtner, H., et al. (2016) Improving Interference Control in ADHD Patients with Transcranial Direct Current Stimulation (tDCS). Frontiers in Cellular Neuroscience, 10, Article No. 72. https://doi.org/10.3389/fncel.2016.00072
[26]
Cosmo, C., Baptista, A.F. and de Sena, E.P. (2015) Contribution of Transcranial Direct Current Stimulation on Inhibitory Control to Assess the Neurobiological Aspects of Attention Deficit Hyperactivity Disorder: Randomized Controlled Trial. JMIR Research Protocols, 4, e56. https://doi.org/10.2196/resprot.4138
[27]
Lipka, R., Ahlers, E., Reed, T.L., Karstens, M.I., Nguyen, V., Bajbouj, M., et al. (2021) Resolving Heterogeneity in Transcranial Electrical Stimulation Efficacy for Attention Deficit Hyperactivity Disorder. Experimental Neurology, 337, Article ID: 113586. https://doi.org/10.1016/j.expneurol.2020.113586
[28]
Kim, J., Kim, D., Chang, W.H., Kim, Y., Kim, K. and Im, C. (2014) Inconsistent Outcomes of Transcranial Direct Current Stimulation May Originate from Anatomical Differences among Individuals: Electric Field Simulation Using Individual MRI Data. Neuroscience Letters, 564, 6-10. https://doi.org/10.1016/j.neulet.2014.01.054
