We will introduce you to some techniques for observing the pulse, and make a few observations on it together. It is then your task, in groups of three, to develop an interesting inquiry using those techniques to explore the regulation of the pulse ("who's in control?"), carry it out, and report your study (motivation, observations, interpretations) here in the lab forum area.
Over 12 seconds -
normal: 87.5 bpm
in 2, out 2: 70 bpm
in 4, out 4: 80 bpm
in 6, out 6: 85 bpm
Over 30 seconds -
normal: 86 bpm
in 2, out 2: 84 bpm
in 4, out 4: 78 bpm
in 6, out 6: 82 bpm
Analysis: Our first set of data was inconsistent with our hypothesis. There didn't appear to be a direct correlation between breathing and heart rate. Over a 30 second interval, the first three data points were consistent with our hypothesis, but the fourth was not, so we cannot draw any definite conclusions.
A possible reason for discrepancies is thats perhaps the body needs a specified amount of time for heart rate to change in accordance with breathing.
We took samples from two subjects: a smoker and a non smoker. Our samples consisted in 20 second intervals where we recorded heart rate before smoking one cigarrete, immediately after smoking a cigarrete and 10 minutes after smoking the cigarrete, to see how pulse was affected over time by smoking in both subjects.
Sarah (smoker) 81
La Toiya (non smoker) 78
La Toiya 90
After 10 minutes:
Sarah's pulse increased by 15 after the cigarrete. After 10 minutes it went by 9 (7 beats away from what it was before smoking).
LaToiya's pulse increased by 12 after the cigarrete. It decreased by 12 after 10 minutes (back to the initial heart rate).
Our observations did not confirm our hypothesis in these two subjects, since our non smoker's pulse increased less than our smoker's pulse, and "recovered" faster.
Hypothesis: Music Affects the Heart rate.
Everyone in the group had their heart rate taken four times. The first time was a control with no music. The second time was with the subject listening to Cuban rap. The third time was a control. And the fourth time was with the subject listening to funky jazz.
Our results were inconclusive. Different people had different results. For example, Shafiqah's highest was the 1st control and the lowest was in the second control. Romina's highest was funky jazz and the lowest was the second control. Paula's highest was the 1st control and the lowest was funky jazz. Vanessa's highest was funky jazz and the lowest was the 2nd control.
Some of the things that might have affected these results would be preferences in music, previous exposure to the songs. These two things appeared to result in lower heart rates for the people in the group. The second control resulted in lower heart rates which could be due to familiarity to the testing procedure as opposed to the first time when people might have been a little nervous or excited about the test.
Variables & Observations:
Coldplay (mellow): 93.19, 94.96, 89.71 --> 92.62
Techno Music: 91.63, 93.92, 97.27 --> 94.27
Sad Thoughts: 96.8, 95.57, 92.33 --> 94.9
Angry Thoughts: 98.06, 93.77, 94.66 --> 95.49
Smoking: 124.8, 113, 107.5 --> 115.1
Heart rate is sensitive to external variables.
External variables affect the heart rate.
Using our data collected from testing mental variables (ie. Sad Thoughts and Angry Thoughts), perhaps it is partially possible for humans to mentally control their heart rates. However, the heart rate seemed to adjust closer to the resting heart rate as time progressed.
Smoking is bad.
Hypothesis for breathing: The less oxygen you take in, the higher the heart rate. e think the heart has to work faster when there is less oxygen coming in, and we've observed that when you hold your breath your heart seems to be pounding.
Control (sitting without moving or talking, breathing normally)
1) 69 beats/min
2) 75 beats/min
3) 93 beats/min
1) 64.5 beats/min
2) 92 beats/min
3) 132 beats/min
1) 69 beats/min
2) 87 beats/min
3) 87 beats/min
Conclusion: some data increased with the lack of air, which would support our hypothesis, but not all the data followed the same pattern. Therefore, we are unable to support the hypothesis with this data.
hypothesis for activity: We think more activity would increase the heart rate. We used only one subject.
Control = 93 beats/min
Resting= 75 beats/min
After jogging in place = 150 beats/min
Conclusion: Our data supports our hypothesis.
We retrieved various pieces of art retrieved from different websites. We had one "dark" piece, one "light" piece, and one "scary/shocking" piece for each. We showed the images to each group member and recorded her reaction.
Light: small decrease in amplitude, no change in frequency
Shock: large decrease in amplitude, " "
Dark: medium decrease in amplitude, but an overall wave pattern, " "
Light: Amplitude falls, no change in frequency
Dark: increase in amplitude, no change in frequency
Shocking: decrease in amplitude w/a slight wave pattern, no change in frequency
Light: smaller decrease in amplitude, no change in frequency
Dark: huge decrease in amplitude, no change in frequency
Happy: increase in amplitude, increase in frequency
Methods: Each member of the group searched the web and found different websites that showed different pictures of art.
First off, the main thing we learned in this lab is that visual stimulus *does* affect heart rate. No matter what image we showed a given group member, she had *some* sort of reaction to it.
The observations support our hypothesis. However, we did not learn exactly how, as there were a number of factors we could not control. For example, the picture was *not* the only thing each group member saw, the art we used varied across different genres/styles/subjects, and we did not have a wide enough sample of different types of images to draw any conclusions about what type of image affects heartrate in what way. We also couldn't be 100% sure what changes were attributed to the visual stimuli themselves and what changes were attributed to the physical act of focusing on the images. Additionally, we had a huge number of technical difficulties, including slow internet, malfunctioning equipment, and difficulty in finding images. To determine with greater accuracy what types of visual stimuli affect heartrate in specific ways, we'd need more time, more subjects, and more images.
We hypothesize that physical activity will increase the heart rate of a person. In order to test this hypothesis we had each member of the group take their standing heart rate. Each member was then subject to a "rigorous" physical test (25 jumping jacks), a second reading was taken immediately following the physical activity.
Resting: 72 beats/minute
After exercise: 112 beats/minute
Increase in beats/minute: 40
Resting: 76 beats/minute
After exercise: 116 beats/minute
Increase in beats/minute: 40
Resting: 92 beats/minute
After exercise: 144 beats/minute
Increase in beats/minute: 52
Resting: 90 beats/minute
After exercise: 120 beats/minute
Increase in beats/minute: 30
Our data supports the hypothesis that exercise will increase a person's heart rate.
Therefore, from our observations, we may further hypothesize that other variables such as physical fitness, or pre-existing health conditions may also affect the number of beats per minute. Stefanie is an athlete who exercises seven days a week, and had both the lowest resting number of beats per minute and the lowest following the physical test. Julia, who lives in Brecon and exercises at the gym about once a week, had the second lowest standing number of beats per minute and the second lowest following the physical test. Mariya, who suffers from asthma which impedes her ability to exercise regularly, had a significantly higher resting heart rate and also a higher rate following the physical test. Alison, who would rather die than exercise, had the highest resting rate and the largest increase in beats per minute following the physical test.
Other variables might include: anxiety regarding the act of performing jumping jacks in front of laughing peers (Alison), the pace at which each subject performed their jumping jacks (Mariya). We suspect that Mariya, who was not as enthusiastic about the testing (and was wearing heels) performed her jacks less rigrously than the other subjects. This might explain why she had the lowest increase in beats between her standing and post-activity heart rate.
We decided to investigate the effects of proximity to another classmate, as well as physical contact with another classmate, on a student's heart rate. Specifically, we measured Patty's seated heart rate while looking at the wall (baseline rate), while looking at Megan from a comfortable distance of about 4 feet, while looking at Megan from a culturally uncomfortable distance of about 1 foot, as well as while Megan patted her shoulder gently and, lastly, gave her a forceful shoulder massage.
Our hypothesis: As compared to the base rate, increasing proximity to another and increasingly forceful touch will correspond with an increase in the seated person's heart rate. That is, a person at a comfortable distance will cause a slight increase in HR from the base rate (of sitting alone), a person at an uncomfortable distance will increase HR even more, a gentle touch will yield an HR that is higher still, and a forceful touch will cause the highest HR of all.
We hypothesize that all of the following things will increase our heart rates:
Holding our breath, Exercise, Smoking
Normal Resting Heart Rate:
Maggie: 60 bpm
Anna: 94 bpm
Adina: 63 bpm
Melissa: 93 bpm
Heart rate while holding breath:
Heart rate while performing abdominal exercise (which does not include Movement):
Heart rate immediately after smoking one cigarette:
From these observations, it appears that heart rate is affected by outside viariables as we have deduced from the above tests. True to our hypothesis, exercise greatly affected heart rate. Holding breath increased heart rate slightly as did smoking. However, there was not as dramatic a difference in these last two cases.
Had we more time, and funding for beds, we would have liked to have ruled out excess stimuli that could have had an affect on the resting heartbeats of our subjects. If we were to test them overnight, it would be interesting to see how dreams affect one's heartbeat. And had we male subjects to observe, how their heartbeat differs from females'.
We hypothesized that standing would increase our control heart rates (sitting down) and that jogging would increase it to an even greater extent.
1. Sitting Down:
Lindsay: 87 bpm
Alice: 99 bpm
Rochelle: 84 bpm
Christina: 84 bpm
Lindsay: 93 bpm
Alice: 102 bpm
Rochelle: 96 bpm
Christina: 102 bpm
3. After Jogging
Lindsay: 105 bpm
Alice: 180 bpm
Rochelle: 165 bpm
Everyone's heart rate increased somewhat while standing, and after jogging around the hall for about thirty seconds it increased significantly for some of us and very little for others. This may be due to the fact that some of us get more exercise on a regular basis. Also some people may have taken longer to run although we all ran the same distance.
We also tested holding our breath while taking our heart rates.
Lindsay: 93 bpm
Alice: 87 bpm
Rochelle: 87 bpm
Christina: 72 bpm
We did not notice a significant difference in the frequencies of heart rates while holding our breaths. However, amplitude was lower than for the other tests and seemed to increase while taking the heart rates for Rochelle and Christina. We inferred from this that after holding our breath for a few seconds, our hearts start to work harder to circulate blood.
From this data we can conclude that some factors that affect heart rate are sitting/standing position, exercise, and respiration.
Hypothesis: External factors will affect the heart rate and amplitude.
Normal Heart Rates
Lara: 88 beats per minute
Ramatu: 88 beats per minute
For the second part of our experiment we told the subject jokes (why was Helen Keller's ear red? Her iron rang. + What did the redneck boyfriend say to his redneck girlfriend when he wanted to break up? We can still be cousins) and read their affected heart rate after.
Lara: We may have miscalculated the heart rate since the bar should have probobly been lowered, however it read 72 beats per minute - The more noticable change was the amplitude. At the highest point - the amplitude increased by 10 millivolts.
Ramatu: again - this calculation may be wrong - 54 beats per minute
But the more noticable amplitude change 10 millivolts.
The third part of our experiment focused on what happens to your heart rate when you lie. Two questions were asked wherein the subject told the truth - then a third question was asked and a lie was told. The answered question for the third was an OBVIOUS lie.
Lara : When she told the truth the amplitude remained steady however, when she lied the amplitude fluctuated. Heart rate 88 beats per minute.
Ramatu: Same results as Lara
Our fourth experiment tested heart rate when pain was inflicted. The pain was in the form of flicks and pinches.
Lara: Amplitude increased by 20 mv when the first pinch occured. The second, more expected time, the amplitude increased by 5. The heart rate remained the same.
Ramatu: Before flick the amplitude was steady - after the flick the amplitude went crazy and remained this way until the end of the trial even though there were two more flicks coming.
We took measurements at 20 second intervals and multiplied the number of beats (number of graph peaks) by three to get beats/minute. These are the data we collected:
At Rest (Baseline): 69 beats/min
Comfortable distance: (about 4-5 feet) 69 beats/min
Uncomfortable distance: (about 1 foot) 69 beats/min
Light Touch: 78 beats/min
Forceful Touch: 81 beats/min
Our data are partially consistent with our hypothesis but partially inconsistent. The fact that Patty's heart rate remained the same regardless of whether Megan was absent, near her, or very very near her suggests that proximity of another person does NOT affect heart rate (we had hypothesized that it would cause an increase). However, the increase from 69 beats/min to 78 beats/min when Megan touched Patty, and the subsequent increase to 81 beats per minute when Megan gave her a forceful massage, suggests a clear trend: having someone touch you will increase your heart rate, and the harder a person touches you, the more your heart rate will increase. This piece of our data is consistent with our hypothesis. Our data suggest, in sum, that proximity has no effect on heart rate, but that heart rate increases proportionally with the forcefulness of touch.
Why? We think physical contact stimulates psychological responses associated with anxiety, which causes an increase in heart rate. With further investigation, we might test whether our findings are statistically significant (not due to chance) and, if so, why that might be so.
Hypotheses: Heart rate is increased by running, lying, and holding your breath.
Maria: heart rate when...
resting 114 beats/min
lying 114 beats/min
running 162 beats/min
holding breath 114 beats/min
Flicka's heart rate when....,
resting 90 beats/min
lying 114 beats/min
running 168 beats/min
holding breath 111 beats/min
Katy's heart rate when....
resting 84 beats/min
lying 84 beats/min
running 159 beats/min
holding breath 75 beats/min
Our observations showed that running had a big impact on one's heat rate, greatly increasing in each case. However, lying had almost no impact on heart rate, except for Flicka's case. Holding breath was more ambiguous because it increased in some cases and decreased in others.
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