Jarrod Bourke
Coloured Stimuli and the effect on Reaction Time
Abstract:
This experiment details the effect that coloured stimuli has on the reaction time of a human being. By conducting this experiment it was proven that colour does affect the human reaction time. By analysing the results many inferences were made. It has been determined that darker colours such as brown influence a human to react slower, where as vibrant colours; such as red result with a much quicker reaction time. These results were obtained by completing a series of reaction time tests with different coloured stimuli. This experiment explores these concepts into further detail and outline colours affected on reaction time.
Introduction:
Reaction time is the measurement of the time elapsed between the stimulus being presented and the following behavioural response.This response could either be pressing a button, eye movement, speaking or another obvious behavioural movement. Therefore reaction time can be expressed as the speed of processing or the efficiency of processing.[2]
The average human reaction time is 0.215s, where the average range is 0.15-0.33s. The mean reaction times for sprinters at the Beijing Olympics were 0.166s for males and 0.189s for females. This form of reaction is tested through sound as the stimulus and then the behavioural response being movement. [2]Reaction time is used in many different human activities. It plays a crucial role in a numerous amount of sports, driving or riding bikes and everyday human life. The main point of interest for this experiment is how reaction time has a key correlation to colours.
Different coloured stimuli play key roles in the reaction time of the human body. Colour is most technically defined as; "Colour is the visual effect that is caused by the spectral composition of the light emitted, transmitted, or reflected by objects."[15]
The human eye has different types of cones with pigments that sense three different portions of the spectrum. Primarily long wavelengths (known as red), middle length wavelengths (sometimes green) and short wavelengths (known as blue). [5]
During this experiment the term “vibrant” will be continually referred to. It means, “(of colour) bright and striking”. As well its opposite “pale”, which means, “light in colour or shade; containing little colour or pigment.”[18-19]
The reason this experiment is being conducted is to determine whether road signs and traffic lights are using the most effective colours to indicate certain instructions. For example if humans react the quickest to a red stimulus, then traffic lights and stop signs, are using the most effective colour. But if not, then maybe the colours of these important indicators need to be revised. This is important because it affects the safety of all human beings. If the indicators aren’t using the most effective colour, and this colour is then changed, the amount of car accidents and incidents on the road could be reduced.
Aim:
The aim of this experiment is to determine how different coloursaffect the human reaction time.
Hypothesis:
The human reaction time is affected by the colour of the stimulus.
Variables:
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Jarrod Bourke
Independent –
- Colour of the stimulus
Dependent –
- The reaction time data/results
Control –
- Continuous subjects – i.e. Use the same people for each individual testing stage
- Environment – i.e. Silent, on your own, indoors
- Preferred hand – i.e. The test subject should use their preferred hand and index finger
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Jarrod Bourke
Risk Assessment:
Risk / PreventionSore Eyes / Space out the time between each test. Don’t do them consecutively.
Materials:
- Laptop
- Range of subjects
Method:
- We went to
- We completed the reaction time tests according to the following stimuli colour options, in a silent environment with the subjects preferred hand and index finger:
Colour of Stimulus
Crimson (Red)
Cornflowerblue (Blue)
Limegreen (Green)
Darkorchid (Purple)
Coral (Orange)
Deeppink (Pink)
Darkslategrey (Greenish Grey)
Darkkhaki (Greenish Brown)
Chocolate (Brown)
- We completed the reaction time tests by following the prompts on the website provided. Plus an additional 5 times for each colour of stimulus.
- We setup the results table as below for each subject:
Subject Name / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
- We recorded results into a result table and made conclusions.
- We repeated steps 1-5 at least 5 times for each subject for more reliable and valid results.
- We repeated step 6 with at least 3 or more subjects.
- Once all data was recorded we made graphs.
Results:
Subject Name:Jarrod / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
Jarrod / Red / 0.249 / 0.229 / 0.216 / 0.282 / 0.253 / 0.246
Jarrod / Blue / 0.241 / 0.245 / 0.288 / 0.243 / 0.249 / 0.253
Jarrod / Green / 0.294 / 0.222 / 0.266 / 0.258 / 0.284 / 0.265
Jarrod / Purple / 0.237 / 0.293 / 0.300 / 0.248 / 0.261 / 0.268
Jarrod / Orange / 0.253 / 0.245 / 0.253 / 0.270 / 0.268 / 0.258
Jarrod / Pink / 0.247 / 0.246 / 0.263 / 0.309 / 0.277 / 0.268
Jarrod / Greenish grey / 0.332 / 0.331 / 0.254 / 0.259 / 0.267 / 0.289
Jarrod / Greenish brown / 0.312 / 0.244 / 0.289 / 0.252 / 0.316 / 0.283
Jarrod / Brown / 0.271 / 0.284 / 0.281 / 0.308 / 0.322 / 0.293
Subject Name / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
Ollie / Red / 0.216 / 0.277 / 0.216 / 0.260 / 0.251 / 0.244
Ollie / Blue / 0.274 / 0.269 / 0.247 / 0.246 / 0.251 / 0.257
Ollie / Green / 0.238 / 0.263 / 0.239 / 0.237 / 0.234 / 0.242
Ollie / Purple / 0.218 / 0.245 / 0.246 / 0.228 / 0.250 / 0.237
Ollie / Orange / 0.258 / 0.262 / 0.236 / 0.275 / 0.247 / 0.256
Ollie / Pink / 0.276 / 0.294 / 0.229 / 0.238 / 0.236 / 0.255
Ollie / Greenish grey / 0.259 / 0.274 / 0.252 / 0.257 / 0.295 / 0.267
Ollie / Greenish brown / 0.321 / 0.251 / 0.306 / 0.271 / 0.296 / 0.289
Ollie / Brown / 0.271 / 0.253 / 0.255 / 0.244 / 0.344 / 0.273
Subject Name / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
Lachlan / Red / 0.273 / 0.249 / 0.241 / 0.239 / 0.213 / 0.243
Lachlan / Blue / 0.241 / 0.261 / 0.244 / 0.259 / 0.142 / 0.229
Lachlan / Green / 0.265 / 0.240 / 0.233 / 0.230 / 0.235 / 0.241
Lachlan / Purple / 0.220 / 0.245 / 0.226 / 0.251 / 0.234 / 0.235
Lachlan / Orange / 0.259 / 0.261 / 0.234 / 0.274 / 0.238 / 0.253
Lachlan / Pink / 0.275 / 0.291 / 0.229 / 0.240 / 0.233 / 0.254
Lachlan / Greenish grey / 0.271 / 0.249 / 0.253 / 0.251 / 0.294 / 0.264
Lachlan / Greenish brown / 0.324 / 0.231 / 0.305 / 0.272 / 0.354 / 0.297
Lachlan / Brown / 0.285 / 0.291 / 0.321 / 0.344 / 0.237 / 0.296
Subject Name / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
Euan / Red / 0.232 / 0.244 / 0.248 / 0.247 / 0.236 / 0.241
Euan / Blue / 0.240 / 0.300 / 0.273 / 0.250 / 0.233 / 0.259
Euan / Green / 0.264 / 0.240 / 0.261 / 0.231 / 0.212 / 0.242
Euan / Purple / 0.258 / 0.221 / 0.236 / 0.259 / 0.278 / 0.250
Euan / Orange / 0.264 / 0.238 / 0.273 / 0.251 / 0.259 / 0.257
Euan / Pink / 0.251 / 0.243 / 0.222 / 0.265 / 0.289 / 0.254
Euan / Greenish grey / 0.235 / 0.293 / 0.270 / 0.268 / 0.284 / 0.270
Euan / Greenish brown / 0.245 / 0.284 / 0.275 / 0.251 / 0.299 / 0.271
Euan / Brown / 0.301 / 0.293 / 0.272 / 0.255 / 0.263 / 0.277
Subject Name / Colour of Stimuli / Test 1 Time (seconds) / Test 2 Time (seconds) / Test 3 Time (seconds) / Test 4 Time (seconds) / Test 5 Time (seconds) / Avg. Time (seconds)
Angus / Red / 0.257 / 0.210 / 0.251 / 0.236 / 0.199 / 0.231
Angus / Blue / 0.259 / 0.271 / 0.222 / 0.215 / 0.231 / 0.240
Angus / Green / 0.234 / 0.210 / 0.283 / 0.272 / 0.261 / 0.252
Angus / Purple / 0.240 / 0.231 / 0.250 / 0.228 / 0.257 / 0.241
Angus / Orange / 0.275 / 0.221 / 0.247 / 0.219 / 0.259 / 0.244
Angus / Pink / 0.263 / 0.242 / 0.221 / 0.257 / 0.241 / 0.245
Angus / Greenish grey / 0.253 / 0.237 / 0.279 / 0.254 / 0.283 / 0.261
Angus / Greenish brown / 0.237 / 0.273 / 0.245 / 0.241 / 0.306 / 0.260
Angus / Brown / 0.248 / 0.283 / 0.316 / 0.251 / 0.259 / 0.272
Subject Name / Colour of Stimuli / Averaged Reaction Time (seconds)
Jarrod / Red / 0.246
Jarrod / Blue / 0.253
Jarrod / Green / 0.265
Jarrod / Purple / 0.268
Jarrod / Orange / 0.258
Jarrod / Pink / 0.268
Jarrod / Greenish grey / 0.289
Jarrod / Greenish brown / 0.283
Jarrod / Brown / 0.293
Subject Name / Colour of Stimuli / Averaged Reaction Time (seconds)
Ollie / Red / 0.244
Ollie / Blue / 0.257
Ollie / Green / 0.242
Ollie / Purple / 0.237
Ollie / Orange / 0.256
Ollie / Pink / 0.255
Ollie / Greenish grey / 0.267
Ollie / Greenish brown / 0.289
Ollie / Brown / 0.273
Subject Name / Colour of Stimuli / Averaged Reaction Time (seconds)
Lachlan / Red / 0.243
Lachlan / Blue / 0.229
Lachlan / Green / 0.241
Lachlan / Purple / 0.235
Lachlan / Orange / 0.253
Lachlan / Pink / 0.254
Lachlan / Greenish grey / 0.264
Lachlan / Greenish brown / 0.297
Lachlan / Brown / 0.296
Subject Name / Colour of Stimuli / Averaged Reaction Time (seconds)
Euan / Red / 0.241
Euan / Blue / 0.259
Euan / Green / 0.242
Euan / Purple / 0.25
Euan / Orange / 0.257
Euan / Pink / 0.254
Euan / Greenish grey / 0.27
Euan / Greenish brown / 0.271
Euan / Brown / 0.277
Subject Name / Colour of Stimuli / Averaged Reaction Time (seconds)
Angus / Red / 0.231
Angus / Blue / 0.24
Angus / Green / 0.252
Angus / Purple / 0.241
Angus / Orange / 0.244
Angus / Pink / 0.245
Angus / Greenish grey / 0.261
Angus / Greenish brown / 0.26
Angus / Brown / 0.272
Colour of Stimuli / Overall Averaged Reaction Time (seconds)
Red / 0.241
Blue / 0.2476
Green / 0.2484
Purple / 0.2462
Orange / 0.2536
Pink / 0.2552
Greenish grey / 0.2702
Greenish brown / 0.28
Brown / 0.2822
Conclusion/Discussion:
The hypothesis that “The human reaction time is affected by the colour of the stimulus” has been supported throughout the entire investigation.
By conducting this experiment many inferences were made which support the hypothesis. With analysis of the results obtained the following inferences support the hypothesis.
- When red was the stimulus colour,it resulted with the quickest averaged reaction time compared to the other colours, with 60% of the subjects. This allows the inference; that red is the colour the human being reacts to quickestto be made.
- The human being reacts to pale colours slowly. This inference is supported in the results as, “greenish grey”, “greenish brown” and “brown”, gave the slowest averaged reaction time as the stimulus across 100% of the subjects.
- The colours “red”, “blue”, “green” and “purple” were continuously in the top 5 quickest averaged reaction times across every subject. With the addition of “orange” it can be inferred that the human being reacts quickly to vibrant colours.
The results include an averaged graph of all the scores obtained. The data provided supports the inferences above. The graph continues to support that when red is the stimulus the reaction time is quicker and shows the “pale” colours to give slower reaction times. The averaged graph shows a trend that is visible in all of the result graphs above.
These inferences each support the idea that “The human reaction time is affected by the colour of the stimulus”.
As the investigation took place, in the results it is seen that as the colour of stimulus (independent variable) changed the reaction time (dependent variable) also changes. The experiment was effective in proving that “The human reaction time is affected by the colour of the stimulus”. The procedure to gather the results needed to make this claim was reliable and valid. By changing the colour of the stimulus, a variety of data was collected and this successfully reinforces the hypothesis.
In future if this experiment was to be conducted again, there are some minor changes that would be made. Firstly, a wider variety of colours could be used in the experimental phase. These colours should then be described in more depth. For more reliability a larger range of subjects could be used. Overall completing this experiment was a pleasure and the results obtained were fascinating and support the inferences that were made.
Science IRP – Second Hand Research
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Author: Kiley Bielecki-Mooney, Caitlin Ascher, Meagan Brozovich
Date Created: Fall 2008
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Date Created:18th of February 2008
Date Accessed:06/03/14
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Date Created:2004
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18. Vibrant – Definition
- (Of colour) bright and striking
19. Pale – Definition
- Light in colour or shade; containing little colour or pigment
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