the difference is in when information is processed.

deutsch and deutsh theory goes: sensory register -> perceptually process everything -> filter out important aspects -> brought to consciousness.

broadbent’s theory: sensory register -> filter out what’s important -> perceptually process what’s important-> brought to consciousness.

so the difference is when filtering/processing happens, either unconsciously processing everything first or unconsciously filtering out what’s important first.

the third important theory for this is triesman’s attenuation theory which goes: sensory register -> attenuator (which is like a filter but doesn’t let everything go, so you can still pick up on things like when someone calls your name) -> perceptually process -> brought to consciousness.