 This psychological conception of mental imagery is neutral about some seemingly important features of mental imagery. If mental imagery is perceptual representation not triggered directly by sensory input, then mental imagery may or may not be voluntarily triggered (see more on this distinction in Section 1.3 below). Further, it may or may not be conscious – even if you experience nothing, as long as there is a triangle in your primary visual cortex, but no triangle on your retina, you have mental imagery (see more on unconscious mental imagery in Section 1.2 below).