Reflexes Lab

In this lab we tested different reflexes of the the body. In class, we learnt that reflexes are involuntary responses due to stimuli. We tested the autonomic reflex (pupil size), knee jerk reflex, the blink reflex, and the plantar reflex. We also tested reflexes in accordance to response time, to see how texting while driving affects our response time.

1. Photopupillary Reflex
This reflex makes the pupil contract when bright light is shone into it. When light was shone into my eye, my pupil rapidly decreased in size. My other pupil was still dilated. After the light was removed, my pupil dilated once more. I think this reflex happens to protect our eyes from bright lights, and in contrast, I think pupils dilate to let more light in and help us see better in dark environments.

Change in pupil size

2. Knee Jerk Reflex (Patellar Reflex)
This reflex makes the lower leg swing out and kick when the spot just below the knee cap is hit. This one is quite odd. I tried telling myself not to kick out, but I genuinely couldn't do anything to stop my leg kicking out. I wonder if this reflex was to move out of harm's way -  before we could think about it, our bodies would have our muscles in our legs moving.

3. Blink Reflex
The blink reflex makes a person blink when something is thrown at them. This one happened, every time a cotton ball was thrown at my face, even through a glass window, I blinked. This reflex is clearly to protect our eyes when things come flying towards our faces.

4. Plantar Reflex
The plantar reflex showed whether a person's toes curled over when the foot was stimulated or if they spread apart. For me, my toes curled over, but if they spread apart, it is a sign of Babinski's, a sign of nerve damage if the test is not being done on a newborn. I think this happens to protect the sole of the foot, the curling of the toes is very characteristic of protecting.

5. Reaction Time Reflex
This reflex is about how fast we react to something we see. We also tested how speed when we were texting. The majority of people slowed right down when they were texting, which teaches us an invaluable lesson about how dangerous texting and driving is. The bar chart below displays the change in reaction time of our class. Our brains react to the images our eyes capture, but while texting, we can't focus solely on paying attention to our surroundings. We can only see our surroundings out of the corner of our eye due to the focus on our phones. Multi-tasking when driving is not safe.