Int. Journal of Electrical & Electronics Engg.
Vol. 2, Spl. Issue 1 (2015)
e-ISSN: 1694-2310 | p-ISSN: 1694-2426
Mobile Phone Handset Radiation Effect on Brainwave Signal using EEG: A Review 1 1
Kuldeep Singh, 2Sandeep Kumar
Department of ECE, National Institute of Technical Teachers Training and Research Chandigarh-160019 2 Departmentof Zoology, Post Graduate Government College, Chandigarh-160011, India 1 Singh.kuldeep2009@gmail.com, 2 Shanty_chaudhary@yahoo.co.in
Abstract—This paper talks about the growing concern in the people about the effect of mobile phone RF radiation on human brainwave signal using various techniques to capture those effects. Linear, Non- linear and statistical methods (t-tests) employed by various researchers to analyze variation in brainwaves.This paper gives comparison between brainwaves like Delta (0.5-4 Hz), Theta (4-8 Hz), Alpha (8-13 Hz), Beta (13-30 Hz) and Gamma (30 Hz-70Hz) in terms of Frequency Progressive map and amplitude progressive tri-maps. Electroencephalography (EEG) gives a noninvasive way of measuring brainwave activity from sensors placed on the scalp of the human head. So, the aim of this paper is to study the effect of RF exposure from mobile phone on Human brainwave as brainwaves Brain wave can provide information of mental state of the individual. Keywords- Mobile phone; brainwaves; EEG; Radiofrequency (RF); Brain; Cognitive
I. INTRODUCTION The use of mobile phone is increasing day by day around the globe, as cell phones have become an integral part of people’s lives. As per the world population clock the total world population is 7,012,000,000 and number of mobile users around the world are 6,800,000,000+ as evaluated in February 2013[1]. Thus, there are 97 phones per 100 citizens. Also India has second largest mobile users around the world with 937,055,980 mobile users from the population of 1,267,402,000. Thus,there are 73.9 mobile phone users per 100 citizens as per TRAI 30 November 2014 Press Release [2].Mobile communication device are used in immediate vicinity of the body, producing high localized RF energy deposition.Frequency band used for mobile are GSM900 or GSM 1800 or WCDMA 2100. Mobile phone emits pulsed high-frequency electromagnetic fields thatmay have some adverse effects on the brain activity and human health. Since mobilephones are used in closedproximity to human temporal region of head as shown in Fig. 1
NITTTR, Chandigarh
EDIT -2015
Fig. 1 Electromagnetic exposure on human brain [3]
In spite of using mobile phone below the permissible SAR level set by Health regulatory body (FCC, WHO,ICNIRP).TheFederalCommunications Commission (FCC) has set a SAR limit of 1.6 W/kg, averaged over a volume of 1 gram of tissue, for the head.In Europe, the limit is 2 W/kg, averaged over a volume of 10 grams of tissue. People encounter various symptoms like sleepiness, dizziness, headache, fatigue, loss of mental attention, heart palpitations, disturbance of digestive system, burning and tingling sensations in the skin of the head, memory loss, brain-tumours, decrease in sperm count, decrease in mobility and many more after the use of mobile phone. Still, there is no accepted evidences with which we can prove these effects are due to RF radiation. Thus, researcher are still finding way to prove the presence of such affects as there is also no proof that shows use of mobile phone is safe for use.Thus, it isnecessary to control the adverse effectscaused by mobilephone radiation on people. It is important to know that all humans brain display five different types of electrical patterns or brain waves across the cortex. The brain waves can be measured with an EEG (electroencephalograph) – a tool that allowsresearchers to record brain wave patterns. Each brainwave has a purpose and helps serve us in optimal mental functioning.Brain is considered to be important unit of central controlling system. As, the nervous system ofhuman is divided into three main system i.e. 164
Int. Journal of Electrical & Electronics Engg.
Vol. 2, Spl. Issue 1 (2015)
Central Nervous System (CNS) which mainly contains Brain and Spinal cord, the Peripheral Nervous system (PNS) and the Autonomic Nervous system(ANS).Brain wave frequencies play a vital role in how successful we are at handling stress, focusing on tasks, and getting a good night’s sleep. If one of the five types of brain waves is either overproduced or under produced in our brain, it can cause problems. Each serves a role to help us cope with various situations whether it is to help us process and learn new information or help us calm down after a long stressful day. Theta and gamma rhythms associated with memory processes or memory formation and also linked with working memory [4].Brainwaves can be divided into five groups mainly delta, theta, alpha, beta and gamma as shown in table 1. TABLE I.
e-ISSN: 1694-2310 | p-ISSN: 1694-2426
Fig. 2 International 10–20 system electrode Placement on scalp of human brain.
BRAINWAVES
Brainwaves
Frequency (Hz)
Amplitude (µv)
Description
Delta
0.5-4
20-200
associated with deep sleep
Theta
4-8
2-100
associated with drowsiness
Alpha
8-13
20-60
associated with relaxed and alert
Beta
13-30
2-20
Gamma
>30
5-10
associated with active thinking or attention associated with event related synchronization of brain Fig. 3
The researchers are trying to study different brainwaves Delta (0.5-4 Hz), Theta (4-8 Hz), Alpha (8-13 Hz), Beta (13-30 Hz), Gamma (30-70 Hz) of physiological interest to come on conclusion whether the mobile phone radiation alter the brain activity or not.Hence EEG machine can be used as a toolfor recording ofbrainwave waves by placing electrodes on the scalp of human brain with a conductive gel or paste as per International 10–20 system with minimum 19 recording electrodes (plus ground and system reference electrode) are used.Fig, 2 shows the placement of scalp electrode on human brain.Fig.3 shows the frequency progressive map for all frequency range used to analyze EEG power spectrum at differentlocation of human scalp. In order to study the results better we can use amplitude progressive Trimaps from three
165
Frequency Progressive map
differentviews,as shown in fig. 4 Many researchers were still finding evidences on how these levels of radiation affect biological tissue and on cognition. Various Biological Effects of Radio Waves were observed by various researchers like sleep disorder, abnormal BP, weakness, fatigue, digestive problems in children, impaired motor function, reaction time, memory and attention [5]. R. M .Isa et al. in [6] have investigated that RF Emission by mobile phone give several effect to brainwave signal and there are significant different between the session of exposure. Brainwave signal were recorded focusing on alpha sub band with frequency range from 8 to 12 Hz using electroencephalograph. It has been observed during Discriminant analysis of Alpha PAR (Power Asymmetry Ratio) gave highest classification percentage in session During with 94.7% and followed by sessionafter with 91.6% as compared to 51.6% in session before mobile phone radiation alters regional cerebral blood flow on sleep and waking EEG Here brain hemisphere dominance is investigated by using Power Asymmetry Ratio.
NITTTR, Chandigarh
EDIT-2015
Int. Journal of Electrical & Electronics Engg.
Vol. 2, Spl. Issue 1 (2015)
In another study, N. Perentos et al. in [7] have investigated the effect of both Pulsed and Continuous radio frequency exposures on Alpha band of the electroencephalogram. Seventy-two healthy volunteers (35 females, 37 males) participated in a single recording session where the eyes open resting EEG activity was recorded and four exposure conditions were presented (sham, pulsed modulated RF, continuous RF, and pulsed low frequency) in a counterbalanced order for 20 min. The mean alpha amplitudes for each condition, and the statistical findings helps to conclude that suppression of the global alpha band activity was observed under the pulsed modulated RF exposure, and continuous RF exposure but no effect was seen in the extremely low frequency condition. Ole Jensen et al. in [8] have discussed recent findings demonstrating human gamma-frequency activity associated with attention and memory in both sensory and non-sensory areas. In recent iEEG studies reported that gamma-frequency power is modulated by the phase of theta-frequency oscillations and oscillatory activity in the gamma-frequency band is related to object representations in humans is supported by a range of studies using EEG and MEG recordings. Attention and maintenance of working memory are reflected by increase in Gamma -band (30–100 Hz) Synchronization. ZunairahHj Murat et al. in [9] investigate the effects of mobile phone radiation on human brainwaves using electroencephalograph (EEG) particularly on alpha wave and thirty samples were taken that make calls from a mobile phone to another party without conversation to minimize artifacts in the EEG signals. The mobile phone was held next to right ear at a distance 2 cm from user’s head. The time frame protocol of the experiment involving three stages (5 min for each session and 1 minrest between each session), which were before, during and after usage of mobile phone.The four electrodes and 2 channels were employed in bipolar connection as per International Standard 10-20 electrode system.By performing statistical Analysis which showed alpha level of the right side decreases significantly during the calls and further decreases within the period of 5 min. after the calls were ended. However, the alpha power of the left side of the head remains invariant throughout the experiment. It has been observed that the increment in the alpha waves shows that, samples are more relaxed, and has higher concentration capability. Also correlation between the alpha left and the alpha right brainwaves signal decreases after 5 min. exposure from mobile phone. James c. Lin et al. in [10] has compared the two studies one was UK investigation and other study was Finlandinvestigation. According to UK study the effect on cognitive function was studied in 18 children who were 10 to 12 years of age, a standard Nokia 3110mobile-phone handset were used for exposures and NITTTR, Chandigarh
EDIT -2015
e-ISSN: 1694-2310 | p-ISSN: 1694-2426
observed that some trends toward faster reaction times, Higher accuracy and higher sensitivity in the presenceof microwave radiation from a GSM cell phone than under sham exposure (power-off) conditions and alsofound that simple reaction-time measurement during
Fig. 4
Amplitude Progressive map
sham exposure was considerably slower significant vale (p-vale = 0.02) than during exposure to 0.025 W and 0.25 W. In other study of Finland recruited twice as many subjects (16 boys and 16 girls), but used a different study design, which involved a two-way counterbalance methodology and it was concluded that RF electromagnetic energy from a standard GSM cell phone had no effect on 10-14 year olds' cognitive function, as measured by response time and accuracy. Roy Luria et al. in [11] examined the time dependence effect of exposure to mobile phone radiation on the cognitive function of human. A total of 48 healthy right handed male subjects performed a spatial working memory task and were divided into three equal groups. Twostandard Nokia TM 5110 GSM phones are attached to both sides of the head by a non- conductive frame and phone were silent during the whole test and was located 1.5 cm away from the subject’s head. Max SAR for Nokia (5110) ranges from 0.54 to 1.09 w/kg. Observation made by author after performing the experiment that Avg RT (Reaction time) of the right hand response under left side exposure was significantly longer than those of the right side and sham exposure groups. It has also been observed that EMF decreased the theta band EEG activity during memory retrieval task and increased the alpha band activity. T. W. Huang et al. in [12] investigated that P300 at Pz location on brain scalp could be used to identify the cards memorization in a subjects’ brain, as amplitude of P300 for target(memorized card) were larger than nonmemorized cards but P300 was affected by long –term memory when recalling the memories in short-term memory. The amplitude of P300 increases from frontal to parietal lobe. Poker cards were used as visual stimuli to evoke ERPs for recognition task by detecting memorized card stored in short-term memory and 166
Int. Journal of Electrical & Electronics Engg.
Vol. 2, Spl. Issue 1 (2015)
observed that memory can be detected by the changes of potentials of brain P300, at Pz location in head. Thus, long-term Memory affected the recognition task of short-term memory. II. CONCLUSION From the above literature survey we concluded that mobile phone RF exposure affects human brainwaves. In spite of using mobile phone below the permissible SAR level set by Health regulatory body (FCC, WHO, ICNIRP) some bio-effects has been observed in mobile user. Where in some researcher recorded the effect in terms of Avg RT (Reaction time) of the right hand response under left side exposure was significantly longer than those of the right side and sham exposure groups and alpha level of the right side decreases significantly during the calls and further decreases within the period of 5 min. after the calls were ended.Attention and maintenance of working memory are reflected by increase in Gamma -band (30–100 Hz) synchronization.EMF decreased the theta band EEG activity during memory retrieval task and increased the alpha band activity. Memory can be detected by the changes of potentials of brain P300, at Pz location in head. Researchers were using different timing protocolwhich results difficulty in to analyze the accurate effect of RF exposure from mobile phone. REFERENCES [1] www.census.gov.in [2]https://trai.gov.in/WriteReadData/PressRealease/Document/PRTSD-Nov-2014.pdf, Press Release No.04/2015.
167
e-ISSN: 1694-2310 | p-ISSN: 1694-2426
[3]https://www.google.co.in/search?q=mobile+phone+radiation [4] Lawrence M. Ward, “Synchronous neural oscillationsand cognitive processes,” Trends in Cognitive Sciences,Vol.7,No.12, pp.553-559, December 2003. [5] Arthur Firstenberg, “Some Biological Effects of Radio Waves” President, Cellular Phone Task Force, September 2001. [6]R.M.Isa,I.Pasya,M.N.Taib,A.H.Jahidin,W.R.Omar,Fuad,H.Norhaz man,S.B.Kutty,S.F.S.Adnan, “Classification of brainwave asymmetryinfluenced by mobile phone radiofrequency emission,” The 9th International Conference on Cognitive Science, Procedia social andBehavioral Science 97, pp.538-545, 2013. [7] N. Perentos, R. J. Croft, R. J. McKenzie, and I. Cosic,“The AlphaBand of the Resting Electroencephalogram Under Pulsed andContinuous Radio Frequency Exposures”, IEEE Transaction OnBiomedical Engineering, Vol. 60, No. 6,pp. 1702-1710, June 2011. [8] Ole Jensen, JochenKaiser , Jean-Philippe Lachaux, “Human Gamma frequency oscillations associated with attention and memory,”INMED/TINS special issue, Trends in Neurosciences Vol.30,No.7, pp. 317-324, May 2007. [9] Zunairah Hj Murat, Ros Shilawani S.AbdulKadir, Roshakimah Mohd Isa, and Mohd Nasir Taib ,” The Effects of Mobile Phone Usage on Human Brainwave Using EEG,” IEEE Computer Society , UKSim 13th International Conference on Modelling and Simulation, pp.36-41, 2011. [10]James c. Lin, “Children's Cognitive Function and Cell-Phone Electromagnetic fields”, IEEE Antennas and Propagation – Magazine, Vol. 47, No.6, pp.118-120, December 2005. [11] Roy Luria, Ilan Eliyahu, Ronen Hareuveny, Menachem Margaliot, and Nachshon Meiran, “Cognitive Effects of Radiation Emitted by Cellular Phones: the Influence of Exposure Side and Time”, Bioelectromagnetics, U.S National Library of medicine, National Institutes of Health, vol. 30(3) pp. 198-204, April 2009. [12] T. W. Huang, Y. J. Tian, Y. H. Tai, K. T. Sun, “Brain waves reflect your memories”, IEEE CPS, Fourth Global Congress on Intelligent Systems, pp. 21- 24, 2013.
NITTTR, Chandigarh
EDIT-2015