Which of the following is typically a result of physiological changes in the nervous system?

Short term memory loss can indeed be a result of physiological changes in the nervous system. These changes can occur due to various factors, such as age, neurodegenerative diseases, stress, or brain injury. As the brain undergoes alterations in its structure or function, it can affect the processes associated with memory formation and retention, leading to difficulties in remembering information over a short period.

In contrast, the other options involve different outcomes that are typically less associated with physiological changes in the nervous system. Improved reflexes, for example, usually indicate enhanced neural pathways and quicker response times, which are typically linked to training or conditioning rather than degeneration. Enhanced visual ability can stem from various factors, including environmental influences and experience, rather than physiological decline. Increased IQ, while influenced by cognitive development and learning, does not directly correlate with the kind of physiological changes that lead to short term memory loss. Thus, while those changes can enhance cognitive functions in some cases, they are not marked by the same degeneration seen in short term memory loss.