Kalafatakis F, Bekiaridis-Moschou D, Gkioka Eirini, Tsolaki Magda
Alzheimer Hellas, Petrou Sindica13, 54643, Thessaloniki, Greece.
Hell J Nucl Med. 2017 Sep-Dec;20 Suppl:146-154.
Concerns about the possible adverse health effects of mobile phones (MP) have increased along with the expansion of their use. A number of research papers have tried to address this issue. Although many investigations concluded that MP use does have negative consequences, in terms of cognitive function of the human brain, the results so far have been divisive. A number of studies reported impairment of cognitive function after exposure to mobile phone electromagnetic field (MP EMF), while others observed no effect or improved performance. The variance in the results may be attributed to methodological issues. The present article focuses on possible effects of MP use on cognitive function and more specifically on working memory processes. An emphasis is placed in the lack of a validated tool, a cognitive task, that can produce MP EMF effects on human cognition in a repeatable fashion.
Sixty four (64) healthy participants as well as 20 with Mild Cognitive Impairment (MCI) were the experimental group, while 36 healthy individuals were the control group. A computerized list of 10 words was presented and the participants were asked to reproduce it. The words were presented very briefly in order to increase the difficulty and hence the sensitivity of the task. Three measurements were taken for the experimental group: a) before using the MP, b) immediately after using the MP for a duration of 5 minutes, c) 5 minutes after the second measurement with no usage of the MP in between. Three measurements of the memory task were also taken for the control group in the same time intervals with no usage of a MP. The effect of age and gender in the performance of the task was taken into account.
Healthy participants of the experimental group performed worst in the memory task after using the MP. While the third measurement (5 minutes after the 2nd measurement) was better than the second (after using the MP), but worse than the first (before using the MP). In contrast for the control group the second measurement was better than the first and the third even better than both previous ones. All differences were statistically significant. The reduction of the performance in the task after using the MP was even higher for the age group of 60-80 years old in comparison with younger age groups, as well as for the individuals with MCI in comparison to healthy participants. Age was significantly negative correlated with performance in the task, while gender showed no significant correlation.
MP use has a significant negative impact on working memory performance of human participants. The effect is apparent even for a 5 minute use of the MP. Working memory deficits are greater not only for the 60 years old and above participants but also for individuals with Mild Cognitive Impairment. These results are in agreement with previous studies on animals as well as humans on the effects of MP use on the brain. It is argued that low sensitivity of some of the cognitive tasks used until now and the lack of a validated tool in the form of a cognitive task may account for some of the variability in the literature so far. It is suggested that the experimental paradigm that was used in this study for an increased sensitivity measurement of cognitive function and working memory processes in particular may be used for the display of the effects of MP use on cognitive function and for the development of other tasks sensitive to it. Overall, it is concluded that the development of certain restrictions on MP use is necessary for the protection of the brain health of the users.
随着手机使用的普及，人们对其可能对健康产生的不利影响的担忧日益增加。许多研究论文试图解决这个问题。尽管许多调查得出结论，手机使用确实会产生负面影响，但就人类大脑的认知功能而言，目前的结果存在分歧。一些研究报告称，暴露于手机电磁场（MP EMF）后认知功能受损，而另一些研究则未观察到影响或性能有所改善。结果的差异可能归因于方法学问题。本文重点关注手机使用对认知功能的可能影响，更具体地说是对工作记忆过程的影响。重点在于缺乏一种经过验证的工具，即一种认知任务，能够以可重复的方式产生手机电磁场对人类认知的影响。
64名健康参与者以及20名轻度认知障碍（MCI）患者作为实验组，36名健康个体作为对照组。呈现一个包含10个单词的计算机化列表，要求参与者复述。单词呈现时间非常短暂，以增加任务难度，从而提高任务的敏感性。对实验组进行了三次测量：a）使用手机前，b）使用手机5分钟后立即测量，c）第二次测量后5分钟，期间不使用手机。对照组在相同时间间隔内也进行了三次记忆任务测量，期间不使用手机。考虑了年龄和性别对任务表现的影响。
实验组的健康参与者在使用手机后在记忆任务中的表现最差。虽然第三次测量（第二次测量后5分钟）比第二次（使用手机后）好，但比第一次（使用手机前）差。相比之下，对照组的第二次测量比第一次好，第三次甚至比前两次都好。所有差异均具有统计学意义。与年轻年龄组相比，60 - 80岁年龄组在使用手机后任务表现的下降更为明显，与健康参与者相比，轻度认知障碍个体的下降也更为明显。年龄与任务表现呈显著负相关，而性别无显著相关性。
手机使用对人类参与者的工作记忆表现有显著负面影响。即使仅使用5分钟手机，这种影响也很明显。工作记忆缺陷不仅在60岁及以上的参与者中更明显，在轻度认知障碍个体中也更明显。这些结果与之前关于手机使用对大脑影响的动物和人类研究一致。有人认为，到目前为止使用的一些认知任务敏感性较低，以及缺乏一种经过验证的认知任务形式的工具，可能是迄今为止文献中存在一些变异性的原因。建议本研究中用于提高认知功能尤其是工作记忆过程敏感性测量的实验范式，可用于展示手机使用对认知功能的影响，并用于开发对其敏感的其他任务。总体而言，得出结论认为，为保护用户的大脑健康，有必要对手机使用制定某些限制。
