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Oneself as a Biological Entity. I. The Heart and its Control

Paul Grobstein's picture

This week we're beginning a set of labs on humans as biological entities ... and a set of labs in which you should use the skills and insights you've developed as a researcher in past labs to develop and carry out your own lines of investigation. 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?" - "the difference between animate and conscious"?), carry it out, and report your study (motivation, observations, interpretations) here in the lab forum area.

ED's picture

Emily & Kristel Heart rates

Emily & Kristel

Heart rates (BPM) without an effect (resting) rounded to 3s.f.:
Kristel: 63.5 , SD: 3.2
Emily: 100, SD: 40.6

Listening to Music (Daft Punk, heavy bass, fast speed):
Hypothesis: that listening to music with a fast tempo and heavy bass will increase Kristel's heart rate.
Kristel: 77.5, SD: 3.70

Listening to Music (Ukulele, soothing song):
Hypothesis: ukulele music will calm Emily down and slow her heart rate.
Emily: 103 SD: 7

Hypothesis: we thought eating would increase heart rate.
Emily: 109 SD: 11.2

Irregular Breating: 
Hypothesis: that irregular breathing would increase heart rate.
Kristel: 52.7 SD: 55.9

Yoga (after doing Yoga):
Hypothesis: that heart rate would be more stable-- or less variance.
Emily: 87.4 SD: 8.6

Talking (emotional issues):
Hypothesis: that it would calm Emily and lower her heart rate.
Emily: 109 SD: 16.7 (however, the graph showing beats/time looked more constant than any other graph for Emily; we believe the SD was actually lower)


We did not think about standard deviation in heart rate at all when we hypothesized for each condition. However, we found that in each experiment, SD that mattered/showed change more often than heart rate. Emily in general had a very high heart rate-- around 100 bpm-- though her variance changed (drastically reduced) when she did things that we hypothesized would calm her down. With Kristel, our hypthesis about music was true: her heart rate increased with techno music. But the other experiment done on Kristel disproved our hypothesis: when she breathed irregularly, her heart rate actually dropped from her resting heart rate-- however, the standard deviation sky rocketed. The only experiment that slowed Emily's heart rate was after having done yoga (87.4). Every experiment done on Emily slowed her SD. But the experiments she did that were more emotional (not so much to do with physically moving her whole body like yoga), her heart rate was still 100 bpm or above.

xhan's picture

Can we control our heart rate?


Everyday we experience random changes in our heart rate. Certain things get our  heart to race, such as.. drinking too much coffee, or listening to intensely moving music. Certain things get us feeling mellow and calm, such as.. watching a baby laugh, or practicing yoga. Why does this happen? Is it only because of external factors? Can an individual's body make-up/genetics/structure have any influence on heart rate? Can we consciously control how fast or frequent our heart beats?


Michelle Yashaswini
Initial 95.3 73.9
Hyper 100.5 102.9
Calm 50.6 82.1



Michelle: My pulse was initially very high(95.3).  In order to determine if i could change my hear rate, i tried to listen to "exciting"music, to test if my heart rate could increase, and tried to breathing techniques and listening to "calming" music to see if i could decrease my heart rate. Although listening to "exciting" music seemed to increase my heart rate-my heart-rate increased from 95.3 to 100.5 listening to "calming" music didnt seem to decrease my heart rate-my heart rate only decreased from 100.5 to 99.8 This however, was still higher than my initial heart rate.  However, when I tried breathing heavily, I noticed a significant decrease in heart rate-from 95.3 to 50.6. I think that breathing heavily decreased my heart rate more than listening to calm music because it was a more direct, "active" attempt to change my heart rate. Although listening to calm music may have decreased my heart rate, it was not significant enough to determine if there was any real change.

Yashaswini: My initial heart rate was relatively low, around 73.9. I consciously tried increasing my rate by thinking of a loved one for a minute. I could feel my veins pounding and on measuring the data recorded, I observed my heart rate had gone up to 102. 9!
In the second part of my experiment, I listened to classical music on my iPod with my eyes closed, while I consciously tried to control my breathing. I could initially feel my veins throbbing a lot, but after a while, my heart rate slowed down to 82.1! Even though this was still significantly higher than my initial heart rate of 73.9, it had gone down a lot compared to the rate it had reached on being stimulated by thought and intense emotion.

After observing the effects loud, bass music, deep breathing, calm music and emotion/thought had on the two of us, we can conclude that our heart rate can be altered, for a short duration, by external factors. We’re not sure if this alteration can be sustained for a long period of time, i.e. if our heart rates can be controlled over a large period of time. Also, we feel that listening to loud music with heavy bass and being over powered by intense emotions increased the tension in our.. muscles (?) and stimulated the release of adrenalin, the “fight or flight” hormone. This is probably what increased our heart rate.
Also, listening to calm music did not have the same effect on the two of us. While the change in Yashaswini’s heart rate was significantly noticeable, the change in Michelle’s was almost negligible. Thus, we also conclude that genetic factors and individual body make-up also affect what factors affect our heart rates and to what extent.



sophie b.'s picture

Sophie and Keshia Heart Rate Lab

In our lab we set out to find if emotions have an effect on heart rate, we believed that our emotions, and stress levels do effect our heart rate, and that videos that were scary would .  In order to find out more, we decided to watch videos that showed graphic violence that would make us scared, and stressed and to watch videos that were funny, or relaxing and would make us happy.

For the first part of the experiment, Sophie watched three trailers for scary movies. During the first movie (Mirrors), Sophie's heart rate spiked once during a particularly violent scene, and thereafter had a higher heart rate . During the second movie (Prom Night) Sophie's heart rate spiked two times. During the trailer for the third movie (Paranormal Activity), which Sophie did not find particularly scary, there was no abnormal activity.

For the second part of the experiment, Sophie's heart spiked two times during the first trailer (Lady and the Tramp)  but for the most part her heart rate was lower. During the second trailer (Arthur) Sophie's heart rate was higher, especially during a scene that had a baby crying and lots of commotion. During the third trailer (The Office) Sophie's heart rate was very consistent and appeared normal.  During the final clip (Christian the Lion) which Sophie was outwardly very excited about, her heart rate was constantly spiking and very erratic.


Not Scary Movies:

Not Scary Movies

Scary Movies:

Scary Movies

Our information has led us to believe that our hypothesis is correct, because Sophie's heart rate only spiked during scenes where she was either frightened, interested or annoyed by the content. Additionally in scenes that Sophie did not find scary or interesting her heart rate did not change. This makes us believe that when we are highly stressed, or very excited our heart rates go up.

lcorhan's picture

Heart Rates and Fear

For this lab our group decided that we wanted to look at the way stress level affects heart rate. From personal experience we felt that when we are anxious about or scared about something in particular our heart begins to beat faster. We believe that this may occur because of the fight or flight instinct in humans which releases adrenaline during "dangerous" situations, therefore when the person is afraid the heart begins to beat faster. In order to test this we decided to watch clips from scary movies and measure our heart rates. Our first few experiments we each took turns on watching a clip or trailer from a scary movie and then our data seemed to show spikes in the amplitud of the heart beat. At first we thought that this supported our hypothesis but then we realized that the spike occured because we moved  or jumped when we were scared. Then we attempted to do a more controlled version of our previous experiment ( person held down the experimentee hand while she was watching the clip). The data that we collected from this experiment did not differen greatly from the average resting heart rate measured in the beginning of class. Based on this evidence our hypothesis is incorrect, however there may have been flaws in the experiment or the technology that we used. 

Paoli, Claire, and Laura


Kalyn's picture

Heart Rate





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Pulse Rate
1.       Karina’s (Subject #1) Normal Pulse Rate: BPM (Beats per minute): 83 STD(Standard Deviation): 4
2.       Kalyn’s (Subject#2) Normal Pulse Rate: BPM (Beats per minute): 115 STD(Standard Deviation): 0
Data Categories
Experiments lasting 6-12 seconds each
1.       Consciously: Breathing rate (Rapid Vs Calm/Slow)-Subject #1
Calm Data: BPM: 82.9 STD:0
Rapid Data: BPM: 79.3  STD:3.1
2.       Thoughts (Scary Vs Peaceful) – Subject #2
Peaceful Thoughts: BPM: 97.9 STD:8.1
Scary Thoughts: 107.3 STD: 1.08
3.       Music (Soothing Vs Erratic/Rock) – Subject #1
Soothing Music: BPM 70.8         STD: 17.5
Erratic Music: BPM: 91.8          STD: 30.9
4.       Oxygen Amount – Subject #2
Normal – BPM: 93.6   STD: 3.4
(Less Oxygen) Held Breath: BPM: 90.8 STD: 1.8
More Oxygen: BPM: 101.5  STD:7.2
5.       Sitting down Vs standing – Subject#1
Standing: BPM: 79.1  STD:2.3
Sitting: BPM: 75.6   STD: 3.3
Calm Breathing Rate is faster because you’re consciously thinking about many things because you can not shut the brain off. Making yourself calm can have the opposite effect on your nerves and thereby directly effect’s your body’s pulse rate. For a rapid breathing rate the body is possibly responding to a single external stimulus causing your conscious to focus on a specific task. Therefore all the blood rushes to the heart out of fight or flight instinct. The body is prepping you for any needed action.
Peaceful thoughts created a slower heart rate compared to the scary thoughts.
Soothing music lowered the heart rate a lot. This is possible due to the subject’s familiarity with the soothing music. Her association with the song and her idea of “calm” could have triggered calm memories. Ex.) Babies and specific nursery rhymes, AOL voice, movie narrator.  Erratic music had the opposite effect and increased heart rate. This may have something to do with the music’s beat and rhythm. Ex.) Nightclub – Loud and fast music.
As you hold your breath the heart stops pumping blood to the body and this decreases the heart rate. When you breathe deeply you’re taking in more oxygen and this increases your heart rate.
Standing requires the blood to circulate throughout the body causing an increase in heart rate. When you sit down circulation is reduced as less blood is needed throughout the body.
Through our experiments we feel that pulse reacts and is triggered by both your unconscious and conscious. These factors are important because they are the starting point for the information that you feed to your body. For instance, if you experience fear (whether it is real with a life or death situation compared to an imagined fear such as watching a horror film) the body takes that response and acts on it. In certain situations the “fight or flight” tendency takes over in order for the body to respond appropriately to the situation at hand. But the mind has to understand the situation at hand in order to properly interpret the fear. In this way three main factors truly effect heart rate which include internal, external and body mechanisms.

jmstuart's picture

In an attempt to find some of

In an attempt to find some of the effects of music on the heart we choose two songs, one up-tempo and one relatively slow, and took our pulse while listening to each. Our first song was entirely instrumental with a slower tempo, utilizing piano, drums, and the acoustic bass. The other song had a faster beat and utilized drums, multiple synthesizers, voices, and electric guitar. We hypothesized that the change in bpm would correspond with the change in the tempo of music. We recorded the following results:


Song One- BPM: 60.4, Standard Deviation 3.8

Song Two- BPM: 62.9, Standard Deviation 4.3


Song One- BPM: 72.6, SD 5.5

Song Two- BPM: 70.0, SD 6.4

Professor Grobstein:

Song One- BPM: 82.4, SD 1.1

Song Two- BMP: 82.9, SD 1.8


Most basically, the data showed that the average bpms did not change much while listening to the two different types of music, but the standard deviation fluctuated more when listening to the uptempo music. We found this data more relevant because this showed not just the numbers themselves, but the changes and reactions while experiencing the music. These sounds might have been louder and more jarring, and therefore caused a greater reaction.


We acknowledge the presence of ambiguity in regard to how music effects the heart rate of an individual. Our reactions to music are often tied up in rhythmic and melodic schemas, as well memory associations. In other words, different people will react to the same song differently (as evidenced by varying tastes in music).


In addition, there are phsical variables to consider, such as height, weight, lifestyle, gender, age, and other pre-existing conditions. Given these variables, our results are just generalizations. Individuals will obviously not only react differently to something as complex as music, but may have innate differences in the body as well.

JPierre's picture

The Effect of Emotionally Based Images on the Heart Rate

We decided to test the effect of emotionally based images on one's heart rate. We chose three scenes from Youtube (sad, scary, and funny) to examine if this would increase or decrease one's heart rate per minute. We hypothesized that the sad images would decrease the initial resting heart rate, while the funny and scary images would increase the initial resting heart rate. We performed the tests twice on subjects Mariah and Anna.

Resting (BPM)
78.5 132.8
Sad (BPM)
74.1 119.0
Scary (BPM) 80.0 126.6
Funny (BPM) 97.0 131.5

Our data supported our story that some emotionally based images influence the heart rate of a person. From the experiences of Mariah and Anna, the sad images decreased their resting heart rates by about 4 BPM and 13 BPM respectively. However, the fear from scary images-which produced an adrenaline rush- increased Mariah's resting heart rate by about 2 BPM, while it decreased Anna's by about 7 BPM. Though Anna's data had the opposite of the presumed affect, this could have been because the "scary" test was done immediately after the "sad" test. When considering this, her heart rate did increase after this test. For the funny images, Mariah's heart rate increased about 18 BPM from her resting heart rate, while Anna's decreased about less than 1 BPM. Again, Anna's data contradicts our hypothesis, but if you consider that this test was performed following the scary test, and in this regard, her heart rate increased.

Thus, our data does not exactly support our story in some instances. We believe that this could be due to some of the limitations we experienced. Firstly, because we did not have access to headphones, we could not factor in the influence of the noise component in this experiment. The noise would have assuredly enhanced the raw emotion in the scenes. Also, the noise in class could have played a role in distracting our subjects from concentrating on the experiment. Furthermore, these scenes and the presumed emotions associated with them were subjective. For instance, Anna did not believe that our "scary" image was that scary, whereas Mariah believed differently.


JPierre (Jennifer Pierre), MCasias (Mariah Casias), Achiles (Anna Chiles)

JyL's picture

Heart Rate

Janice Lee, Debbi Chin, Herman Marcia

Hypothesis: Audio and Visual Stimuli affect heartbeat.

Resting State: Janice - 83.6865 BPM
                       Debbi - 96.0241 BPM
                       Herman - 90.9707 BPM

Different stimuli: Janice - (Sad music video) 85.48 BPM
                          Debbi - (Chill music video) 93.449 BPM
                           Herman - (Funny music video) 94.48 BPM

From the data, one could conclude that audio and visual stimuli does in fact affect the heart rate of an individual. The reactions that audio and visual stimuli evoke is also a crucial factor in the heart rate. If given more time, we would research whether the combination of audio and visual stimuli has more affect on an individual than exposing the individual to audio stimuli and visual stimuli separately.

Although we conducted this test, it does not appear to be a reliable one in measuring heartrate amongst an array of individuals when exposed to different stimuli. Each individual reacts differently to different stimuli and one person's definition of something sad differs from another person's definition of something sad.

Terrible2s's picture

Heart rate and youtube videos

We looked at the effect of emotions on heart rate. We did this by taking our resting heart rate with no stimulation, then taking our heart rate while watching scary, funny, and sad video clips.
Resting heart rates:


Mean BPM

Standard deviation

Scary video heart rates:


Mean BPM

Standard deviation

Funny video heart rates:


Mean BPM

Standard deviation

Sad video heart rates:


Mean BPM

Standard deviation

We found that our heart rates were lower while watching scary and funny movies, but that our heart rates didn't change much while watching the sad video. However, the standard deviations seemed to change drastically from the resting heart rate for every trial. It seemed to get higher during the funny and scary videos, especially the scary videos. During the sad video, it seemed closer to what it was during the resting trial, but was still higher.
Although we noticed trends, we can't fairly draw any conclusions from our data. This is partially due to our lack of trails, possible distractions, and our personal feelings toward the videos. We had trouble finding consistencies in the data, mostly due to individual variation.
-Terrible2s, Lili

Paul Grobstein's picture

Heart rate: a trick question about life

Resting heart beats, Wednesday lab

83.7, 90.9, 96.0, 72.8, 84.0, 80.9, 64.6, 132.8, 72.4, 114, 80.6, 78.5, 84.9 (avg 87)


Resting heart beats, Thursday lab

70, 86, 89, 94, 74, 77, 90, 78, 63, 100 (avg 82)


What is the normal heart rate?

There isn't one.

What is the average heart rate?