This is even looser and 'softer' than conditioning. Learning is relatively more voluntary than conditioning. An imprint is a type of software that has become built in hardware, termed 'firmware' in computer jargon, being impressed upon tender neurons before they were fully developed, or modified at some point when they are singularly vulnerable. Imprinting is extremely difficult to change once the imprint has been made. Some think that imprinting is impossible to change, period.
Imprints are the non-negotiable aspects of our individuality.
Out of the infinite possibilities of programs existing as potential brainware, the imprint establishes the limits, parameters, perimeters within which all subsequent conditioning and learning must occur. Before imprinting the consciousness of the infant is a clean slate, it's 'formless and void'. Another analogue is the exploded or unconditioned consciousness the mystics call enlightenment. When the first imprint is made structure begins to take form. And in a sense it becomes the structure.