Final answer:
In MRI, the k-space signals on the left are from early in the echo (center of k-space, contrast information), whereas those on the right are from later in the echo (peripheral areas of k-space, spatial resolution).
Step-by-step explanation:
The k-space on the left side of each row is signal that occurs early in the echo, while those on the right side are obtained later in the echo. In the context of magnetic resonance imaging (MRI), k-space is a term used to describe the data acquired by the MRI scanner before it is transformed into an image. The signals on the left side of k-space correspond to the initial part of the collected signal or echo, which is related to the center of k-space providing the image's contrast information. Those on the right side are later echoes contributing to the spatial resolution of the image, associated with the peripheral areas of k-space.