In this activity, you will investigate in detail one example showing how the sensory nervous system both dissects and integrates information before sending that information to the brain. By dividing a sensory field into small areas that can be monitored individually, sensory neurons extract detailed information that is then integrated by combining features within and between receptive fields to determine the relationships between stimuli. One of the general principles that you will apply is the concept that nerve cell depolarization opens calcium channels, and then the influx of calcium triggers exocytosis of synaptic vesicles and neurotransmitter release. Nerve cell hyperpolarization makes it less likely that calcium channels will open so that there will be less of a chance for calcium to signal neurotransmitter release. Your class photocopy handout includes more details on each cell type in the retina.
Web links provide additional explanations.
The retina - A simple description. Then look at a white wall in bright light. Look at the wall through a dark opaque tube with one eye, and compare that brightness to the brightness of the wall as seen through the other eye without the tube. Your textbook does not have enough detailed information to help you understand this process, so fill in the details be referring to the photocopy provided and to the recommended web-based Source materials. The same recommended web resources are listed within CourseInfo and as part of this CPR assignment.