Final answer:
The readout portion of a pulse sequence in medical imaging encodes signal data through frequency, which is essential for creating spatial maps in MRI scans.
Step-by-step explanation:
The readout portion of the pulse sequence reads or encodes the signal data through frequency encoding. This process is a fundamental aspect of medical imaging techniques such as Magnetic Resonance Imaging (MRI). Frequency encoding involves applying a gradient magnetic field during the signal acquisition phase; this allows the MRI machine to assign specific frequencies to signals coming from different spatial locations within the body. As a result, the MRI is able to construct a spatial map of the body tissue's response to the magnetic field, enabling the formation of detailed cross-sectional images.