Effects of Multi-sensory Stimulation on the Cognitive

Characteristics of Nursery Facilities

Jung-Min Kim1, Myung-Ho Kim1

1 Department of Building Equipment & System Engineering, Gachon University

Abstract. In this study, EEG(electroencephalogram) and Vibra images were

compared and analyzed in an environmental test room. The images were

obtained by providing multi-sensory stimulation (four types of sound

fluctuations, three sound volume levels, three color/temperature values, and

three fragrances). The aim was to determine the optimal multi-sensory

stimulation and to increase the cognitive characteristics of the nursery facilities.

The environmental test room specifications were as follows: temperature, 25 °C;

relative humidity, 50 RH%; air current speed, 0.02 m/s; and illumination, 1000

lux. At a sound fluctuation of a = 2.1968 (music) and color temperature of

2,700 K, for lavender scent, the relative Mβ and SMR/θ increased, and the

Vibra images of tension and anxiety decreased. Therefore, multi-sensory

stimulation of sound fluctuation a = 2.1968, sound volume 30 dB,

color/temperature 2,700 K, and lavender scent led to an increase in the

cognitive characteristics.

Keywords: Cognitive characteristics, EEG, Nursery facilities, Multi-sensory

stimulation, Vibra image.

1 Introduction

Nowadays, the comfort level of the indoor air conditioning and heating is evaluated

based on the extent of human activity, amount of clothing, and four factors related to

the thermal environment (temperature, mean radiant temperature, air velocity, and

humidity). This method is used for evaluating the comfort level of indoor thermal

environment and for controlling the indoor environment[1]. Humans have five senses,

namely, touch, sight, hearing, smell, and taste. However, at present, buildings

worldwide employ temperature and humidity sensors instead of the human senses for

controlling the interior thermal environments. Therefore, multi-sensory augmented

direct digital control (DDC) that can stimulate the five human senses was developed

to increase the comfort level, productivity, and concentration and to decrease the

energy consumption. Against this background, in this study, single-sensory

stimulation was carried out under different conditions of sound, color/temperature,

and fragrance in a steady-state environmental test room under identical conditions of

temperature 25°C, relative humidity 50 RH%, illumination 1,000 lux, and air velocity

0.02 m/s(ASHRAE).

Advanced Science and Technology Letters Vol.118 (Mechanical Engineering 2015), pp.64-68

http://dx.doi.org/10.14257/astl.2015.118.13

ISSN: 2287-1233 ASTL Copyright © 2015 SERSC

2 Method

2.1 Conditions of the environmental test room

The specifications of the environmental test room were as follows: temperature, −10

to 40°C (error range ±0.5°C); humidity, 20 to 90 RH% (error range ±3 RH%); and

illumination, 0 to 2,000 lux (error range ±3 lux).

2.2 Selection of stimulus conditions

The selected auditory stimulus conditions were expressed in terms of the sound

fluctuation index, a: a = 2.1968, 3.1109, 2.2805, and 2.9293. The visual stimulus

conditions were selected based on the color/temperature (2700 K, 5000 K, and 6800

K)[2]. The olfactory stimulus conditions were selected based on the fragrance (lemon,

rosemary, and lavender)[3].

2.3 Measurement and analysis of physiologic signals

The subjects in this experiment were six kindergarten students, all aged 6. Their

activity levels were set to be 1 met (metabolic rate: 1 met = 58.2 W/㎡) when they

rested on chairs under comfortable thermal conditions. The clothing-weight state was

unified (about 0.65 clo)[4]. Brain waves were measured using PolyG-I (Laxtha Inc.),

which is a specialized bio-signal-measuring device. To analyze the brain waves

quantitatively, each measurement was taken for 5 min based on the analytical unit.

Vibra images were studied using Vibra image 7 program (Vibra System Inc.); using

these images, three parameters, namely, tension and anxiety, stress, and balance were

measured and analyzed by using a webcam[5].

3 Experimental results

3.1 Variation in cognitive characteristics with sound fluctuations

The relative Mβ and SMR/θ measured from the EEG and the tension and anxiety as

determined from the Vibra image with variations in sound fluctuation are shown in

Fig. 1. Relative Mβ was increased by an average of 14.45%, and SMR/θ increased by

an average of 7% when a = 2.1968. Tension and anxiety decreased by an average of

8.26%. The result of ANOVA for relative Mβ and SMR/θ are listed in Table 1.

Advanced Science and Technology Letters Vol.118 (Mechanical Engineering 2015)

Copyright © 2015 SERSC 65

Fig. 1. Variation in relative Mβ, SMR/θ, and tension and anxiety due to sound fluctuations

Table 1. Statistical analysis of relative Mβ and SMR/θ

Sum of Squares DF Mean Square F Value Pr > F

Relative Mβ 0.003 23 0.001 18.133

SMR/θ 0.084 23 0.008 6.281

3.2 Variation in cognitive characteristics with sound volume

The relative Mβ and SMR/θ measured in the EEG and tension and anxiety from the

Vibra image with variations in sound volume are shown in Fig. 2. Relative Mβ

increased by an average of 27.93%, and SMR/θ increased by an average of 11.23%

for a volume of 30 dB. Tension and anxiety decreased by an average of 13.11%. The

result of ANOVA for relative Mβ and SMR/θ are listed in Table 2.

Fig. 2. Variation in relative Mβ, SMR/θ, and tension and anxiety due to sound volume

Table 2. Statistical analysis of relative Mβ and SMR/θ

Sum of Squares DF Mean Square F Value Pr > F

Relative Mβ 0.002 17 0.001 14.307

SMR/θ 0.126 17 0.030 7.456

Advanced Science and Technology Letters Vol.118 (Mechanical Engineering 2015)

66 Copyright © 2015 SERSC

3.3 Variation in cognitive characteristics according to temperature

The relative Mβ and SMR/θ from the EEG and tension and anxiety measured from

the Vibra image with variations in temperature are shown in Fig. 3. Relative Mβ

increased by an average of 23.54%, and SMR/θ increased by an average of 21.67%

for a temperature of 2700 K. Tension and anxiety decreased by an average of 8.54%.

The results of ANOVA for relative Mβ and SMR/θ are listed in Table 3.

Fig. 3. Variation in relative Mβ, SMR/θ, and tension and anxiety due to color temperature

Table 3. Statistical analysis of relative Mβ and SMR/θ

Sum of Squares DF Mean Square F Value Pr > F

Relative Mβ 0.001 17 0.003 7.723

SMR/θ 0.053 17 0.011 6.002

3.4 Variation in cognitive characteristics according to fragrance

The relative Mβ and SMR/θ from the EEG and the tension/anxiety measured from the

Vibra images with variation in fragrance are shown in Fig. 4. Relative Mβ increased

by an average of 17.59%, and SMR/θ increased by an average of 16.66% for lavender

scent. Tension and anxiety decreased by an average of 11.11%. The result of ANOVA

for relative Mβ and SMR/θ are listed in Table 4.

Fig. 4. Variation in relative Mβ, SMR/θ, and tension and anxiety due to fragrance

Advanced Science and Technology Letters Vol.118 (Mechanical Engineering 2015)

Copyright © 2015 SERSC 67

Table 4. Statistical analysis of relative Mβ and SMR/θ

Sum of Squares DF Mean Square F Value Pr > F

Relative Mβ 0.003 17 0.001 26.265

SMR/θ 0.088 17 0.020 12.581

4 Conclusion

The results of the experiment showed that the conditions of sound fluctuation a =

2.1968, color temperature 2700 K, and lavender scent were effective in increasing the

concentration and cognitive characteristics, and in decreasing tension and anxiety.

The aim was to improve the comfort level and concentration and productivity of the

humans in the environment. However, through research and consideration of more

stimulation conditions, the optimal multi-sensory stimulation condition was judged to

be dependent on the occupant's mental state and the purpose of the interior space.

Acknowledgement. This work is supported by the National Strategic R&D

Program for Industrial Technology (10044828, Development of augmenting

multisensory technology for enhancing significant effect on service industry), funded

by the Ministry of Trade, Industry and Energy (MOTIE).

References

1. D.S.Song, “Indoor environment control of well-being generation”, Korean Society of

engineering facilities, Vol.35, No.1, PP.6-8, 2006.

2. S.H.Baik, “Effects of Correlated Color Temperature of LED Lighting Sources on Visual

Performance and Preference”, Kyung Hee University, pp.9, 2009.

3. B.C.Min, “Factor Structure of Imagery on Odors : The Difference Between Gender”,

Korean Society of Emotion and Sensibility symposium the autumn, pp.419, 1999.

4. J.W.Choi, H.H.Lee, “The Relationship between Weight of Single Garments and Thermal

Insulation with a Thermal Manikin”, The Korean Society of Clothing and Textiles, Vol.33,

No.2, pp.173-186, 2009.

5. V.A.Minkin, N. N. Nikolaenko, “Application of Vibraimage Technology and System for

Analysis of Motor Activity and Study of Functional State of the Human Body”, Vol.42,

No.4, Biomedical Engineering, pp.196-200, 2008.

Advanced Science and Technology Letters Vol.118 (Mechanical Engineering 2015)

68 Copyright © 2015 SERSC