BIOLOGY 103 FALL, 2002 LAB 7

Right side Left side
Diana : Feet- .291 .141
Shin - .125 .114
hands - .055 .016
chest - .231 .041
head - .022 .062
Mande : feet - .244 .231
shin - .248 .247
hands - .281 .278
chest - .197 .091
head - .092 .073
Our hypothesis held true for mande ,the closer we moved to the brain, the faster the reaction time. For Diana, either she doesn't have a brain or ah aha, or our hypothesis does not hold true. Notably, the reaction times for Diana's head and hands were similar indicating that perhaps the amount of nerve endings have an effect on the time of a reaction from a tactile stimulus.

We ran the tactile test multiple times, focusing on the differences a change in the location of the touch would make in reaction time. All tests run on bare skin.

Muscle reaction time: .076

First Location (10 trials): HAND- Average reaction time: .0318

Second Location (5 trials): LOWER ARM- Average reaction time: .0616

Third Location (5 trials): FOREHEAD- Average reaction time: .0078

Fourth Location (5 trials): LOWER LEG- Average reaction time: .0128

We concluded that the reaction time was not much affected by the changing of locations, with the exception of the forehead.

Visual
CT - 0.212
HP - 0.250
LS - 0.239

Tactile
CT - 0.226
HP - 0.207
LS - 0.273

Muscle Contraction Time
CT - 0.078
HP - 0.074
LS - 0.086

Based on our results, we believe that our anticipation and the expectation of the sound/visual/tap may have accounted for some of our faster reaction times. We hypothesize that if the subject was preoccupied and could not hear the click of the mouse, then the reaction time would be slower and more accurate to what it would be without any anticipation.

We took our test subject (Heather) and put headphones on her while she tried to memorize a poem in Russian. The stimuli (taps and beeps) were given at random to help create a more realistic reaction. Our results are as follows:

Audio: 0.331, as opposed to the previous experiment's result of 0.179
Tactile: 0.286, as opposed to the previous experiment's result of 0.207

We believe that our results would be more accurate given a more realistic setting. The more the subject is consumed with their present activities the slower their reaction time becomes.

Christine Traversi
Heather Price
Laura Silvius

Experiment One-
Reaction Time to Beeps, Pokes, and Flashing things...
(All numbers in milliseconds)

Kate
Aud median-
186
Vis median-
183
Tac median-
126
Median Muscle contraction time-
49

Katie
Aud median-
202.5
Vis median-
213
Tac median-
158.5
Median Muscle contraction time-
63

Kyla
Aud median-
202.5
Vis median-
238.5
Tac median-
260.5
Median Muscle contraction time-
70

Experiment 2
Location of Poke!!! Our next inquiry is what difference in response time does it make if you are poked on different places of your body?
Our points of inquiry will be
finger tips
back of the hand
palm of the hand
face (forehead)
Experiment 3
Then we will test out random placements on the body and see what kind of variation in response time occurs.

Each place was tested with ten trials, all on Kate.
#2
Collected Data:
Finger Tips
302, 123, 108, 7.81x10^-3, 178, 55, 78, 109, 155, 244
Median-116
Back of Hand
119, 119, 97, 184, 59, 130, 161, 270, 192, 122
Median-126
Palm of Hand
127, 139, 122, 127, 172, 142, 114, 152, 130, 170
Median-134.5
Face (Forehead)
25, 178, 166, 142, 144, 164, 284, 134, 127, 112
Median-143
#3
Collected Data:
Random Placements
back of hand-195
right bicep- 180
right quadracep- 194
right elbow- 227
right calf- 203
right side of head- 164
right forearm- 205
forehead- 120
left calf- 212
left bicep- 166

Conclusions:
#2- The fastest reaction time was for the finger tips. The slowest reaction time was for the face (forehead). We assume from this experiment that reaction time varies for different physical locations, and that areas with faster reaction times have more nerve endings.

#3- The subject did not know where she would be poked and therefore could not anticipate the sensation. This affected her reaction time -- in general the reaction times are longer than the medians for experiment #2 (the anticipated areas). We realize that we did not perform an adequate amount of tests (due to time constraints) but we believe that the data gives us reason to conclude temporarily as such.

........auditory...........visual..........tactile........muscle contracion
kb......0.91...............0.110...........0.292..........0.059
sf......0.225..............0.300...........0.1835.........0.0405

These are the medians of ten trials. The data shows that there is visaul difference. The visual seems to be slightlyslower than the auditory, however the tactile is not consistantly faster or slower than either of the other two tests. This is not suprising becuase there are only two subjects.... the trends were much more easily seen after looking at the class's data.

different places on the body

.......head..........finger tips........shins
kb.....0.334.........0.300..............0.315
sf.....0.1735........0.159..............0.1615

the response times for the finger tips were faster for each of us. this may be because we use this our fingers for touch more regularly and are therefor conditioned to respomd quickly to touch there, or we may have more sensory equipment for touch on our finger tips either on the the fingertips or in the wiring of the sensors to the brain. again it may be helpful to see trends in a larger tested group. our original hypothesis that distance from the brain would have a direct relationship to the response times of the sensory stimulas.

Body reaction time to different "triggers"

SARAH:
Auditory-.159
Visual-.137
Tactile-.175
Muscle contraction-.044

Yarimee:
Auditory-.260
Visual-.206
Tactile- .109
Muscle contraction- .049

Jen:
Auditory-.100
Visual- .131
tactile- .166
Muscle contraction- .044

from these results, it is obvious that there is something else that plays into reaction time because muscle contraction only accounts for a very small number in this.

We attempted to account for some of the other reasons for the reaction time. Jen experimented with being poked in different areas of the body, with her eyes closed so that she could not expect where we would poke her next. She was testing whether not knowing where she would be poked would affect reaction time because in the original tests, all pokes were limited to the forearm. Yarimee tested reactions time with her glasses off, and Sarah tested with her glasses off and sat about 7 feet away. Both the visual tests were to determine whether reaction time would be affected by how clearly we could see the pop-up box. We hypothesized that reactions times for all the tests we chose would increase.

Mean results:
Jen- .316
Yarimee- .216
Sarah- .200

Conclusion: As it turned out, our hypotheses were right, and reaction times increased with the varying tests. The difference between Yarimee and Sarah's original and new reaction times especially proved that not being able to clearly see the visual stimulus affected reaction time because Sarah's reaction time greatly increased when she could barely see the screen, and Yarimee's reaction time slightly increased, and she was much closer to the screen.

Introduction: An experiment was carried out to see if the right and left hands respond differently to visual stimuli. Our hypothesis is that the right-hand responses will be faster than the left-hand ones.

Methods: We used an analogue digital input-output system and a computer program called SuperScope to measure the reaction times of the left and right hands to visual stimuli.
Observations:

Avg. right-hand response to visual stimuli :
RH-.1940ms
MB-.2356ms
AW-.3410ms
CR-.1870ms

Avg. left-hand response to visual stimuli :
RH-.2099ms
MB-.2777ms
AW-.3228ms
CR-.2712ms

Conclusions: Since we are all right -handed, we are more comfortable using our right- hands than our left -hands. Therefore we can't determine whether variation between the right-hand responses and the left -hand responses resulted from being conditioned for right-hand usage or by some other factor such as inheritance. This experiment could have been modified to test visual stimuli responses for the right and left eyes too.

The first experiments (aud, vis, tactile, muscule contraction)
were done with everyone and are as follows:

Heidi- .0986 .168 .1626 .0674
Chelsea- .111 .204 .1728 .0396
Mer- .1312 .1562 .544 .0396
Diana .148 .1852 .191 .0804
Michelle- .1686 .3046 .215 .0784

Heidi and Chelsea did three separate experiments. First, they performed a conrol, second they recorded their response times while having a conversation, and lastly, Mer joined them for a stimulating intellectual conversation.

CONTROL
Chelsea- .1982
Heidi- .0962

Conversation (Heidi and Chelsea)
Chelsea- .2557
Heidi- .2396

Conversation #2 (Heidi, Mer, Chelsea)
Chelsea- .2232
Heidi- .1651

Any active distraction increases reaction time, and when two distract a third, concentration is still affected, but slightly less than talking to only one other person. We believe this is because it takes less concentration to follow a conversation involving three people than two (you actually have to listen when you are the only one expected to respond to the other person's comments).

Maggie S-W, Emily Senerth, Laura Bang

Our initial results were:

For the second experiment we each did different things to play around with the visual test. Emily and Maggie did the test with their right hand, and alternated which eye they covered. Laura did the test without her glasses on. Emily has contact lenses, and Maggie should have glasses but doesn't. And Laura's glasses aren't very strong, so she can still see fairly well without them, it's just a bit fuzzy.

Both of Maggie's second trials were faster, but only by about 0.005 seconds. Since this is such an insignificant difference, covering one eye probably didn't really effect the outcome. Both of Emily's second trials were faster than her original times as well -- her right eye/right hand was 0.02 seconds faster, and her left eye/right hand was 0.007 seconds faster. Laura's results from her second trial averaged about 0.03 seconds slower.

Laura's slower results without her glasses is what we expected, since it seems reasonable that the sharper your vision is the faster you would be able to react. However, her results are the only ones that really support this hypothesis. Maggie's vision is slightly worse when she closes one eye, so we expected her results to be slower, but her reaction time was about the same. Emily should have 20/20 vision in each eye since she has contacts, so seeing out of one eye shouldn't have effected her reaction time. We believe the decrease in her reaction time is due more to familiarity with the test than improved vision.

Rosie: Audio - .2211
Visual - .2293
Tactile - .1919
Muscle contraction - .07

Annie: Audio - .142
Visual - .2416
Tactile - .1637
Muscle contraction - .044

For the second experiment we first tested Audio when one person was having a conversation with the person who was being tested.
The average reaction time for this was .2186.

We then tested the reaction time for Touch when the person's eyes were closed and they were hit randomly anywhere on their body. The average reaction time for this was .1638.

Finally we tested the reaction time Visually. The person watched the screen with only one eye open. The reaction time for only the right eye was .3008 and the reaction time for the left eye was .2374. The person was using their right hand to click.

From this experiment we concluded that for Audio it was much faster when the person was not being distracted. Annie originally had .1416 as her reaction time, but when she was being distracted her reaction time was .2186. It almost doubled. For Visual reaction time, we concluded that when the eye on the same side as the hand that clicks the button is open, the reaction time is slower. For the right hand and right eye, the reaction time was .3008. For the right hand left eye, the reaction time was .2186.

Hypothesis: When standing, your tactile reaction time will be slower than when you're sitting. And, furthermore, different parts of the body (i.e. arm v. leg) would yield different reactions times.

Conclusions: However, we discovered that neither criteria made any difference. Our results remained the same, despite the location of the hit and the difference between sitting and standing.

Sitting:

Jodie: arm-.161
leg- .172

Carrie: arm-.187
leg-.227

Lauren: arm-.146
leg- .213

Lawral: arm- .326
leg- .213

Standing:

Jodie: arm-.189
leg- .172

Carrie: arm- .187
leg- .247

Lauren: arm-.130
leg- .194

Lawral: arm-.198
leg- .223

Hypothesis: When standing, your tactile reaction time will be slower than when you're sitting. And, furthermore, different parts of the body (i.e. arm v. leg) would yield different reactions times.

Conclusions: However, we discovered that neither criteria made any difference. Our results remained the same, despite the location of the hit and the difference between sitting and standing.

Sitting:

Jodie: arm-.161
leg- .172

Carrie: arm-.187
leg-.227

Lauren: arm-.146
leg- .213

Lawral: arm- .326
leg- .213

Standing:

Jodie: arm-.189
leg- .172

Carrie: arm- .187
leg- .247

Lauren: arm-.130
leg- .194

Lawral: arm-.198
leg- .223


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