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Bio 103, Lab 7: Oneself as a Biological Entity. II. Reacting

Paul Grobstein's picture

In last week's lab, we noticed that a part of oneself (the heart) was influenced by but not fully under the control of other parts of oneself. In this lab, we want to further develop the idea that oneself consists of an array of parts that interact with one another to give what we observe as behavior.


A touch starts signals moving in sensory neurons which eventually cause signals to move in motor neurons which eventually cause muscle contractions and movement. How long does it take to move when one is touched, and why? How much of that time is the time it takes for signals to move from the endings of sensory neurons to the endings of motor neurons? How much of that time is the time it takes muscles to contract and cause movement? That's what we'll be looking at in the first part of the lab, and studying further in the second part


Following the demonstration, you and your team should develop your own questions and observation protocols to explore some interesting aspect of what is going on in reacting. For example, would you expect the time taken to be different if the stimulus occurred at a more distant location on the body? On the same side as the response as opposed to the opposite side? If the response was with your dominant or your non-dominant hand? Would you expect the time to change if you were tired? preoccupied? had recently had coffee? Is it the time that signals take within the nervous system that changes or is it the time for muscles to contract and cause movement? Or both?


Don't try and answer ALL the questions. Pick one (or think up one) that you're interested in and have a guess about. And collect enough data so you have some confidence in your conclusions about that situation. And write up your question/hypothesis, observations, conclusions in the lab forum.

LuisanaT's picture

mind vs matter

Its interesting how important anticipation can be in life. Because being aware of astimulus not only causes alertness in the individual, but can also evoke certain emotions that are associated with certain actions. If you are see a needle getting closer to your arm to draw blood you might go stiff, catch your breath, or jerk your hands unnecessarily. The same could have happened in this last experiment we all participated in, making conciousness another factor to take into consideration. Because of this, it is hard to interpret our reactions to certain stimuli properly This may all boil down to the idea of nature vs nuture. There seems to be a fine line between a relex and a reaction that is done quickly. It isn't easy to distinguish between that which has become a habit, subconcious behavior and innate.
LuisanaT's picture

Luisana, Crystal, Eri

Hypothesis:

The fact that each hemisphere of the brain corresponds to the opposite side of the body has lead our group to believe that there will be a deay in reaction time depending on the position of the body that is being stimulated and the side of the body that is reacting to it. The reponse time should be longer when the side of the body that is being stimulated, hit with the hammer, is also the side of the body that is the reaction to it, the hand that presses the button.

Conclusion:

We found that the whole theory of the alternative hemisphere that we initially predicted was partially correct. When we stimulated the left leg and had the right arm react to it it did so much more quickly than if this occured on the same side of the body. We only had some information that supported this idea but if this experiment were repeated with more trials, the outcome would be more accurate and render a more conclusive result.

 

 

             
             
             
             
             
             
             
             
             
           
T1 T2 T3 ND MD RT  
11.597 11.913 11.991 0.316 0.078 0.394 Right arm (s) Right
6.518 6.789 6.853 0.271 0.074 0.374 Left arm (s) Left
4.631 4.789 4.852 0.158 0.073 0.231 Left leg (s) Left
4.791 5.006 5.058 0.215 0.052 0.267 Right leg (s) Left
20.631 20.781 20.839 0.15 0.058 0.208 Right arm (s) Left Arm
4.085 4.322 4.367 0.237 0.045 0.282 Left arm (s) Right Arm
11.804 11.993 12.042 0.189 0.049 0.238 Left leg (s) Right Arm
5.683 5.843 5.912 0.16 0.069 0.229 Right arm Spinal Cord 
8.676 9.068 9.108 0.392 0.04 0.432 Left arm Spinal Cord
Sharhea's picture

Shanika, Sharhea, LaKesha

We decided to test the relationship between the distance and the response. We think that the distance from the brain, actually makes a difference from when we responded. We measured the Neutral Delay(ND), the Muscle Delay (MD), and the Response Time (RT). First, Sharhea was hit along the arm, from the bottom going up. The table below illustrates when she was looking and when she was not looking at the trigger.

 

T1 T2 T3 ND MD RT  
1.263 1.619 1.694 0.356 0.075 0.431 Sharhea not looking - going up the arm
9.316 9.714 9.774 0.398 0.06 0.458  
14.461 15.105 15.16 0.644 0.055 0.699  
20.191 20.607 20.68 0.416 0.073 0.489  
      0 0 0  
0.235 0.251 0.32 0.016 0.069 0.085 Sharhea looking - going up the arm
2.366 2.435 2.561 0.069 0.126 0.195  
6.005 6.139 6.216 0.134 0.077 0.211  
9.022 9.047 9.117 0.025 0.07 0.095  

 

Then we did Shanika, a set of times on the bottom of her arm and the top of the arm. We also did it for her looking and not looking.

 

0.658 0.849 0.88 0.191 0.031 0.222 Shanika - bottom arm
3.273 3.397 3.407 0.124 0.01 0.134  
7.39 7.497 7.521 0.107 0.024 0.131  
             
11.46 11.594 11.642 0.134 0.048 0.182 Shanika - top arm
14.641 14.755 14.795 0.114 0.04 0.154  
18.037 18.127 18.145 0.09 0.018 0.108  
             
0.913 0.998 1.033 0.085 0.035 0.12 shanika - bottom arm looking
2.69 2.52 2.542 -0.17 0.022 -0.148  
5.498 5.518 5.56 0.02 0.042 0.062  
             
9.211 8.882 8.912 -0.329 0.03 -0.299 shanika - top arm looking
11.456 11.307 11.431 -0.149 0.124 -0.025  
13.476 13.634 13.736 0.158 0.102 0.26  

We ended up with a lot of mixed data. For Shanika, this experiment was a lot of fun. When Shanika was looking, she actually pressed the trigger before we hit her, she anticipated the hit before it actually occured. Sharhea first set of data (looking) actually proved our hypothesis wrong. As we got closer to the brain the time did increase, rather than decrease. Our second hypothesis, we assumed that when we are looking our ND, MD and RT will decreased. It actually happened for myself and Shanika

kcough's picture

Neuron Behavior

Kaitlin Cough, Elizabeth Harnett

Our hypothesis was that reaction time would be slower if you were distracted, and it did not matter how far the stimulus was from the brain: it would still react at the same time. We did four different experiments testing neuron behavior. Kaitlin and Elizabeth were both tested. Constant: we always poked on the hand, with exception of the foot trial.

Experiment 1: Poking the hand without any distraction.

Elizabeth

 

t1

t2

t3

ND

MD

RT

 

1.106

1.233

1.278

0.127

0.045

0.172

 

1.955

2.103

2.151

0.148

0.048

0.196

 

2.812

2.913

2.964

0.101

0.051

0.152

 

Kaitlin

 

t1

t2

t3

ND

MD

RT

4.37

4.508

4.561

0.138

0.053

0.191

6.494

6.6

6.65

0.138

0.05

0.188

10.214

10.34

10.392

0.126

0.052

0.178

Experiment 2: Poking on the foot without distraction.

Elizabeth

2.467

2.661

2.708

0.194

0.047

0.241

4.04

4.167

4.199

0.127

0.032

0.159

7.301

7.459

7.501

0.158

0.042

0.2

Kaitlin

 

6.982

7.114

7.156

0.132

0.042

0.174

8.931

8.995

9.092

0.064

0.097

0.161

13.418

13.573

13.636

0.155

0.063

0.218

Experiment 3: Poking on the hand while talking on the phone.

Elizabeth

 

1.005

1.224

1.289

0.219

0.065

0.284

19.684

20.073

20.121

0.389

0.048

0.437

27.064

27.374

27.408

0.31

0.034

0.344

Kaitlin

 

15.281

15.532

15.592

0.251

0.06

0.311

16.794

16.97

17.051

0.176

0.081

0.257

20.596

20.842

20.902

0.246

0.06

0.306

 

Experiment 4: Poking on the hand while reading.

Elizabeth

10.874

11.19

11.247

0.316

0.057

0.373

26.534

26.817

26.854

0.283

0.037

0.32

39.302

39.518

39.575

0.216

0.057

0.273

Kaitlin

10.865

10.956

10.996

0.091

0.04

0.131

13.912

13.993

14.058

0.081

0.065

0.146

7.462

7.627

7.684

0.165

0.057

0.22

 

We discovered that our first hypothesis was correct: if you were distracted, then the reaction time was much longer. This could especially be seen while we were talking on the phone. However, our second hypothesis was slightly disproven. We found that distance from the brain did have an effect on reaction time, even though the reaction time was not as slow as when we were distracted.

Our story: Don't talk on your cell phone when your driving!

Distance from the brain has a slight effect on reaction time, though nothing as drastic as distractions (reading, talking, etc.) Maybe a next step could have been to test the effect of music on reaction time, because usually when you are driving you are listening to music.

 

ekim's picture

on stimuli & response.

Vivian Cruz, Saskia Guerrier, Eurie Kim

Hypothesis
Distance affects response time: the farther away the stimuli, the slower the response.

Observations
Vivian

T1 T2 T3 ND MD RT    
1.52 1.588 1.645 0.068 0.057 0.125 same-side arm
               
10.696 11.055 11.114 0.359 0.059 0.418 same-side stomach
               
15.508 15.658 15.766 0.15 0.108 0.258 same-side thigh
               
10.696 10.739 10.815 0.043 0.076 0.119 other-side arm
               
9.592 9.672 9.739 0.08 0.067 0.147 other-side stomach
               
8.651 8.761 8.841 0.11 0.08 0.19 other-side thigh

Saskia

T1 T2 T3 ND MD RT    
8.886 9.06 9.131 0.174 0.071 0.245 same-side arm
               
5.936 5.991 6.063 0.055 0.072 0.127 same-side stomach
               
4.095 4.191 4.257 0.096 0.066 0.162 same-side thigh
               
10.478 10.565 10.656 0.087 0.091 0.178 other-side arm
               
12.102 12.387 12.483 0.285 0.096 0.381 other-side stomach
               
12.125 12.318 12.449 0.193 0.131 0.324 other-side thigh


Our story
There seems to be no correlation between the distance of the stimuli and the response time (nor in neural delay, nor in muscle delay).
However, we did discover that the neural delay times correspond to the response times because the neural (neurons being transmitted to the brain and back) process directly affects the physical reaction of the person.
Therefore, the faster the neural process, the faster the reaction.
The muscle delay did not correspond to the speeds of neural delays nor response times. Since muscle delay reflects the muscle movement, any muscle movement could have been picked up in the process of the person's thumb pressing the button (for instance, one could've just moved the thumb one time, but the next time one may have moved her wrist and thumb).
Thus, there is no correlation in distance of stimuli versus response time because regardless of where the stimuli is, the person will respond, BUT that response time will depend on CONCENTRATION more than distance.

This could mean that response and reflex is fundamentally different because response is controlled depending on one's concentration, while reflex is more an automatic response.

So what does the automatic-ness of one's reflex depend on?

Rachel Tashjian's picture

Hit Me Baby, One More Time.

We decided to test the difference in response time between genders (male and female). We hypothesized that there is indeed a difference, and that male response time would be quicker. We tested this by hitting the stimulator on the back of the subject's left hand. Here is our data:

 

T1 T2 T3 ND MD RT
Average
2.514 2.709 2.757 0.195 0.048 0.243  
2.93 3.115 3.239 0.185 0.124 0.309  
4.19 4.407 4.457 0.217 0.05 0.267 0.214
13.686 13.747 13.793 0.061 0.046 0.107  
17.122 17.184 17.291 0.062 0.107 0.169  
6.979 7.089 7.129 0.11 0.04 0.15 0.135
6.732 6.841 6.901 0.109 0.06 0.169  
4.23 4.329 4.43 0.099 0.101 0.2  
6.712 6.86 6.921 0.148 0.061 0.209 0.193
20.192 20.307 20.374 0.115 0.067 0.182  
15.65 15.77 15.812 0.12 0.042 0.162  
11.395 11.524 11.593 0.129 0.069 0.198 0.181

 

The first average (first three sets of data) is Rachel's, the second is Andy's, the third is Kate, and the fourth is THA PROFESSAH Wil Franklin.

Therefore, we believe that our story that men have faster reaction times than women is a good one. However, we do not think it's as simple as that. While creating our hypothesis, we also considered the length of the nerve endings (height). While it seems that the reaction time does not differ because of height regardless of gender, we believe that within gender the height difference has an effect. For example, Wil Franklin (6'3'') had a slower reaction time than Andy (5'8''), and Rachel (5'8'') had a slower reaction time than Kate (5'4'').

Kate, Andy, & Rachel

Jen's picture

MARIE HAS SUPERPOWERS O.O

We hooked electrodes up to Paige and Marie and poked them with the poker tool beginning with the foot, then the leg, then the arm, and then the head.

 

TRIAL 1 – Marie

 

Foot:

Neural delay: .11 seconds

Muscle delay: .06 seconds

Response time: .17 seconds

 

Leg:           

            Neural delay: .10 second

            Muscle delay: .03 seconds

            Response time: .13 seconds

Arm:

            Neural delay: FLAWED ATTEMPT

            Muscle delay:

            Response time:

Head:

            Neural delay: .02 seconds 

            Muscle delay: .04 seconds 

            Response time: .06

 

TRIAL 2 – Marie

 

Foot:

            Neural delay: 0.28 seconds 

            Muscle delay: 0.04 seconds 

            Response time: 0.32 seconds

 

Leg:

            Neural delay: 0.15 seconds 

            Muscle delay: 0.05 seconds 

            Response time: 0.2

 

Arm:            

Neural delay: FLAWED ATTEMPT

            Muscle delay:

            Response time:

 

Head:

            Neural delay: FLAWED ATTEMPT

            Muscle delay:

            Response time:

 

 

 

 

 

TRIAL 1 – Paige

 

Foot:

Neural delay: 0.23 seconds 

Muscle delay: 0.1 seconds

Response time: 0.33 seconds

 

Leg:           

            Neural delay: 0.19 seconds 

            Muscle delay: 0.06 seconds 

            Response time: 0.25 seconds

Arm:

            Neural delay: 0.17 seconds

            Muscle delay: 0.05 seconds

            Response time: 0.22 seconds

Head:

            Neural delay: 0.15 seconds

            Muscle delay: 0.33 seconds 

            Response time: 0.48 seconds

 

TRIAL 2 – Paige

 

Foot:

Neural delay: 0.15 seconds 

Muscle delay: 0.04 seconds 

Response time: 0.19 seconds

 

Leg:           

            Neural delay: 0.3 seconds 

            Muscle delay: 0.08 seconds

            Response time: 0.38 seconds

Arm:

            Neural delay: 0.19 seconds

            Muscle delay: 0.07 seconds 

            Response time: 0.28 seconds

Head:

Neural delay: 0.02 seconds

            Muscle delay: 0.06 seconds 

            Response time: 0.08 seconds

 

Our hypothesis was that the closer we poked the test subject to their arm (the place where the electrodes were), the faster their response time would be. Based on our current observations, this appears to be correct.

Marie also has superpowers because in these results and in subsequent tests (data not published here), Marie responded at almost the exact same time as poked, leading to almost zero reaction time.. This leads us to belive that she could possibly have extrasensory perception, as there is no other explanation; she did not hear anybody coming and we did not give her the opporunity to anticipate it. 

Catrina Mueller's picture

For our experiment, we were

For our experiment, we were testing to see if caffine had any effect on a person's reaction time. We first tested all of our base scores. Here are the averages.

Samar: ND- 0.169 seconds, MD- 0.0383, RT- 0.2057

Catrina: ND- .1255, MD- 0.0475, RT- 0.173

Ruth: ND-0.188, MD- 0.333, RT- 0.245

 

Then we tested the caffeinated Samar after she chugged one can of normal Red Bull. Her new average times were

Samar (caffeinated): ND- 0.065, MD- 0.036, RT- 0.1013

As you can see, Samar's times were decreased after taking the caffine, especially the neural delay. We think that caffine has some effect on the central nervous system, which decreases the reaction time. Our observations support the story, found in Samar's first webpaper, that caffeine binds to neural receptors.

A further question we could explore is how caffeine withdrawal effects reaction time. We could test one of us (probably Ruth, who is an addict) after not having had any caffeine, and see what kind of effect it has.

Kendra's picture

Oneself as a Biological Entity: Reacting

Kyree Harmon

Kerlyne Jean

Kendra Sykes

We began our experiment hoping to determine whether the distance of the stimulus from the response button affected the response time. We hypothesized that the farther away the touch was from the button, the longer the response time would be. We performed one trial for a touch to the head, the arm, the knee, and the toe for each member of our group. We were sure to always touch on the left side for control purposes.

The results of our experiment were such: ND stands for Neural Delay, MD for Muscle Delay, and RT for response time.

Head ND MD
RT
KH .04s
.16s
.2s
KS .207s
.054s
.261s
KJ .109s
.064s
.173s

 

Arm(standard) ND MD
RT
KH
.23s
.11s
.34s
KS
.114s
.091s
.205s
KJ
.239s
.078s
.317s

 

Knee ND
MD
RT
KH .30s
.06s
.36s
KS
.35s
.019s
.37s
KJ
.13s
.06s
.19s

 

Toe ND
MD
RT
KH
.17s
.14s
.31s
KS
.28s
.028s
.316s
KJ
.19s
.05s
.24s

 

According to our observations, the further away the touch, the longer the reaction time was generally. HOWEVER, our times were not the slowest for the touch that was farthest away. Though the times for the toe test were slower than those of the arm test, they were not the slowest of all though the toe was the farthest of all. These findings do not support our initial hypothesis, but we were still able to make several other interesting observations.

Firstly, KJ had the fastest reaction time for every test except the arm which happened to be the first test and the test that we were the most preoccupied during. KS had the slowest reaction time for every test except the arm also. We believe that this may have something to do with the fact that KJ is an athlete and athletes frequently are trained and drilled to improve response time. We also noticed that KH had one of her slowest response times during the arm test where she was barely awake. This suggests a connection between mental state and reaction time, and we would like to run further tests including on tired students, preoccupied students, and caffeine stimulated students.