Final answer:
The phrase 'Drink Cola' flashing too quickly for conscious perception on a screen constitutes a subliminal message. This is below the absolute threshold, which is the minimum intensity required for a stimulus to be detected 50% of the time.
Step-by-step explanation:
In the scenario where the words "Drink Cola" flash on a screen but are not perceived because the presentation is below the viewer's absolute threshold, the message is an example of a subliminal message. The absolute threshold is defined as the minimum intensity of a stimulus that is needed for it to be detected 50% of the time. In contrast, a stimulus that is not detectable either because it is too faint or because it is presented too quickly to be consciously perceived, as in this example, is operating in the realm of the subliminal.
Subliminal messages are thought to be perceived by the sensory system but do not enter conscious awareness. Although there's been interest in the effects of subliminal messaging in advertising and media, research suggests that such messages have minimal impact on behavior outside controlled settings. It's also relevant to mention Weber's law, which states that the just noticeable difference (jnd) for a stimulus change is proportional to the original stimulus intensity, although it doesn't apply directly in subliminal perception.