Final answer:
Increasing slice thickness decreases the detail (spatial resolution) as more tissue is grouped into one slice, causing fine details to merge and become less distinct.
Step-by-step explanation:
Detail, or spatial resolution, is the capacity of an imaging system to distinguish small objects as being separate from each other. When the slice thickness is increased in an imaging system, spatial resolution is compromised. Thicker slices mean that more tissue is captured in one slice, which can cause fine details to be lost, as separate structures may now appear to be part of the same slice. Conversely, thinner slices improve spatial resolution by capturing less tissue per slice, allowing for a more precise separation of structures and features within the tissue.
Understanding the principles of optical systems, especially in regards to microscopes, helps us appreciate this concept. Microscopes use light or electrons to magnify small objects, and factors such as wavelength and numerical aperture influence the resolution. A shorter wavelength and higher numerical aperture both lead to better resolution, so similarly, slice thickness inversely affects detail; the thinner the slice, the greater the detail and sharpness of the image produced.