5 or 7?? I can easily imagine much more things simultaneously: 1, 2: 2 cars are parked at the side of the road 3: a third car is driving and going to pass th

5 or 7?? I can easily imagine much more things simultaneously: 1, 2: 2 cars are parked at the side of the road 3: a third car is driving and going to pass the 2 parked cars. 4: a cat runs out from between the parked cars on the street 5: a dog chases the cat 6: with a pulled taut leash 7: pulling the dog's owner on the sidewalk out of balance, 8, 9: causing the owners hat to fly off, and her groceries to fall out of her free arm 10: a fourth car crashes into the surprised car 11: an elderly couple looking at the scene in pure horror ... Now if you meant we could only hold 5 or 7 scenes or complex thoughts at once, then yeah, that could be true depending on the complexity of those thoughts or scenes.