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Life Sciences => Physiology & Medicine => Topic started by: dgt20 on 13/02/2018 07:49:22

Title: factors affecting human reaction CNS experiments
Post by: dgt20 on 13/02/2018 07:49:22
What are some experiments that could be conducted that test on factors that affect human reaction like vision, hearing, touch, etc. Any more complex one other than the basic ruler drop one? I was thinking of testing human reaction at different sound levels but are there any other good ones with good research info on it?
Title: Re: factors affecting human reaction CNS experiments
Post by: evan_au on 13/02/2018 09:15:33
A simple visual test consists of an LED, a button, and a digital timer.

Instruct the person to press the button the instant they see the LED turn on. This starts an electronic counter that counts the milliseconds until they press the button.

To test hearing, you could do the same with a beeper instead of a LED - just select a beep sound that goes to maximum volume very quickly.
Title: Re: factors affecting human reaction CNS experiments
Post by: dgt20 on 13/02/2018 11:26:29
A simple visual test consists of an LED, a button, and a digital timer.

Instruct the person to press the button the instant they see the LED turn on. This starts an electronic counter that counts the milliseconds until they press the button.

To test hearing, you could do the same with a beeper instead of a LED - just select a beep sound that goes to maximum volume very quickly.

How about one where the rooms light is at different brightness (i.e: dark, normal, bright)  and the subject has to press a button when they see LED turn on? would that work?
Title: Re: factors affecting human reaction CNS experiments
Post by: Colin2B on 13/02/2018 11:49:01
Yes, tests the ability to see the light in various background lighting and pupil dilation. Worth testing angle relative to straight ahead. try different colours and intensities.
You can do similar with sound against a background noise level, different source directions, frequencies etc.
Title: Re: factors affecting human reaction CNS experiments
Post by: dgt20 on 13/02/2018 11:52:51
Yes, tests the ability to see the light in various background lighting and pupil dilation. Worth testing angle relative to straight ahead. try different colours and intensities.
You can do similar with sound against a background noise level, different source directions, frequencies etc.

What do you mean angle relative? Could you expand please sounds interesting.
Title: Re: factors affecting human reaction CNS experiments
Post by: Colin2B on 13/02/2018 13:06:39
You are probably aware there are two kinds of cells in the retina - rods and cones. The cones are better at high light levels and the rods are for low light levels. The cones are more concentrated in the center of your eye, while the rods are more spread out. So by looking straight ahead but allowing a dim object eg a star or dim light to be just off to one side, you rely more on your rods, which allows you to see dimmer objects better. This effect is called averted vision - a useful trick to help your night vision.

Exactly how far off-center you should look for max sensitivity varies from person to person. For most people, it's between 5 and 20 degrees away from looking straight ahead. The point is not to look directly at the object.

You will also notice colour sensitivity differences because the rods are black/white sensitive cones colour and greater acuity.