GAC013 Assessment Event 1: Scientific Investigation and Report
Sensitivity Difference in Various
Parts of the Body
Student’s name: Sung Woo Park
Student ID:
HUK21963
Teacher:
Sunny Chung
Due Date:
12 July 2012
Word count:
887
Table of Contents
Abstract ................................................................................................................................................... 1
1.0 Introduction:...................................................................................................................................... 1
2.0 Methodology ..................................................................................................................................... 1
3.0 Research Results ............................................................................................................................... 2
4.0 Discussions ....................................................................................................................................... 2
5.0 Conclusion and Recommendation .................................................................................................... 3
Appendices.............................................................................................................................................. 4
References ............................................................................................................................................... 7
GAC013 AE1
Sung Woo Park HUK21963
Abstract
Tactile sensation is different in various body parts. The paper presents
tactile sensation differences
in each body part, method for the sensitivity experiment, measuring decimal points when subjects felt
two points poking as a
single point poking. The purpose of the experiment is to know sensory spots’
distribution for programs that are needed. Results show agreement with hypothesis and significant
figures of touch sensation on each body part. The work presented here has helpful implications for
future studies of remote control operation in hospital and realistic simulation program.
1.0 Introduction:
This research will provide an overview of tactile sensation difference on
various parts of the body
by experiment. When people are injured, some body parts in the same degree, the location of injured
area is highly relational to feel of pain whether the scar is deep. It is because distribution of pain spots
is different in each part. By measuring skin sense spot at different parts, this statement is proved.
Palms will be more sensitive and have more sensory spots than elbows and back side of the neck,
because hands are used in delicate works.
2.0 Methodology
Measuring device, two toothpicks
fixed at a ruler by using two rubber bands, are used
in poking
subjects to test for different sensitivity in parts of the body. Subject's body parts are poked by this
measuring device until they feel two points poking as one point being poked. The distance of the
last points is recorded. Three different parts of body, palm, elbow, and back side of neck are tested and
20 subjects participated in this experiment.
12/7/2012
page 1
GAC013 AE1
Sung Woo Park HUK21963
3.0 Research Results
Average distance between two points
in the palm was about 6.15mm. Elbow and back
side’s length was about 12.55mm and 14.85mm, respectably followed by palm. Palm’s
distance was the shortest among the length measured in the
body parts. The distance
measured on the neck is two times longer than the one in the palm significantly. However,
those in the elbow and back side of neck had similar figures that their subtraction was only
1.9mm. It tends to be more sensitive as length is short.
4.0 Discussions
As body parts have different number of pain spots, the palm is predicted to be more sensitive and to
have many sensory spots than the elbow and back side of the neck. According to the results of this
experiment, the palm, elbow, and neck have different lengths of two points that are considered
as
one spot. This length supports how many pain spots exist in certain parts. Distance rate tells
sensitivity have a tendency that length is directly proportional to sensitivity, the same meaning as
sensory spots’ number. So, palm is thought to be about two times more
sensitive than neck because
distance of neck is double to that of the palm. Because of similar length between neck and elbow, they
are considered that they have alike sensitivity. However, the elbow is predicted to be slightly more
sensitive than the neck. In
comparing the distance between two spots in different parts of body, the
hypothesis is thought to be right.
According to BMC Musculoskeletal Disorders, by pressure pain threshold test, the upper
region of the trapezius and low back were the most sensitive in back side of body while the
lower part of neck-shoulder region was the least. In addition, there was no difference between
left and right side and gender in tactile sensation difference in parts of body. In the research
by Attention, Perception, & Psychophysics, the research shows the sensory threshold difference
12/7/2012
page 2
GAC013 AE1
Sung Woo Park HUK21963
between young and older adults. As tactile measurement, two different frequencies of vibratory
stimuli were tested for measuring absolute thresholds. As a result, young adults are more sensitive
than older adults. According to the Departments of Anatomy and Orthopaedic Surgery, Oxford, “Each
unit of skin is formed with more than one nerve fiber.”(Weddell, G.) This means that sensory spots in
the skin are related to nervous systems which affect sense of touch.
The investigator could study the method of making acupressure machine which has different
strength at dissimilar parts by knowing sensitivity of each body part. However, everyone has
different sense of touch and the acupressure machine has strength control function, so tactile
sensitivity is not that important
in making acupressure machine. In other aspect,
establishing standard of sense of touch contributes to making visual reality system. Unlike
other senses, tactile sensitivity of visual reality system should be measured for realistic simulation.
Users can feel adjustment in the sense of touch while playing in visual reality program, thanks to
general standard tactile sensation data. Furthermore, general standard tactile sensation data is useful to
remote control operation by robot. When doctors operate patients using a robot, doctors perform
better with proper feedback from robot to their hands.
5.0 Conclusion and Recommendation
To identify that each part of body having dissimilar sensitivity and pain spots, measuring length of
sensory spots was done by using certain device that is made with two toothpicks. This experiment was
run by measuring the length of two points that is felt as one point at palm, neck, and elbow. As a result
of the experiment, palm’s distance was the shortest and that means it is the most sensitive among all
three. The elbow was second and the neck was the last and that means they are duller thanthe palm. In
conclusion, different parts of body have different sensitivity. The sensitivity of touch is proportional to
distribution of sensory spots. This result could be used
in setting up standard sensitivity and
in
realization of visualized accident experiment like car crash.
12/7/2012
page 3
GAC013 AE1
Sung Woo Park HUK21963
Appendices
Figure 1.
12/7/2012
page 4
GAC013 AE1
Sung Woo Park HUK21963
Figure 2.
12/7/2012
page 5
GAC013 AE1
Sung Woo Park HUK21963
Figure 3.
12/7/2012
page 6
GAC013 AE1
Sung Woo Park HUK21963
References
“Hearing and Touch Sensitivity may be Genetically Linked.” Asian News Internationa n/a. ProQuest
Central Basic. May 14 2012. Web. 5 July 2012 .
Binderup, Asbjørn T., Lars Arendt-Nielsen, and Pascal Madeleine. “Pressure Pain Sensitivity Maps of
the Neck-Shoulder and the Low Back Regions in Men and Women.” BMC Musculoskeletal
Disorders 11.1 (2010): 234-. ProQuest Medical Library. Web. 8 July 2012.
Dickstein, R., R. J. Peterka, and F. B. Horak. “Effects of Light Fingertip Touch on Postural Responses
in Subjects with Diabetic Neuropathy.” Journal of Neurology, Neurosurgery and Psychiatry
74.5 (2003): 620-6. ProQuest Central Basic; ProQuest Medical Library; ProQuest Nursing &
Allied Health Source. Web. 5 July 2012.
Humes, Larry E., et al. “The Effects of Age on Sensory Thresholds and Temporal Gap Detection in
Hearing, Vision, and Touch.” Attention, Perception and Psychophysics (pre-2011) 71.4
(2009): 860-71. ProQuest Central Basic; ProQuest Medical Library. Web. 11 July 2012.
J.M.S. Pearce. “The Law of Specific Nerve Energies and Sensory Spots.” European neurology 54.2
(2005): 115-7. ProQuest Central Basic; ProQuest Medical Library. Web. 11 July 2012.
Weddell, G. “The pattern of cutaneous innervation in relation to cutaneous sensibility.” Departments
of Anatomy and Orthopaedic Surgery, Oxford (1941):346–367 J Anat. Web. 11 July 2012
12/7/2012
page 7