Two major theories have fueled a now 1,500 year-long debate started by Saint Augustine: Is consciousness continuous, where we are conscious at each single point in time, or is it discrete, where we are conscious only at certain moments of time? In an Opinion published September 3 in the journal Trends in Cognitive Sciences, psychophysicists answer this centuries-old question with a new model, one that combines both continuous moments and discrete points of time.
“Consciousness is basically like a movie. We think we see the world as it is, there are no gaps, there is nothing in between, but that cannot really be true,” says first author Michael Herzog, a professor at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland. “Change cannot be perceived immediately. It can only be perceived after it has happened.”
Because of its abstract nature, scientists have struggled to define conscious and unconscious perception. What we do know is that a person moves from unconsciousness to consciousness when they wake up in the morning or awake from anesthesia. Herzog says that most philosophers subscribe to the idea of continuous conscious perception–because it follows basic human intuition–“we have the feeling that we’re conscious at each moment of time.”
On the other hand, the less-popular idea of discrete perception, which pushes the concept that humans are only conscious at certain moments in time, falls short in that there is no universal duration for how long these points in time last.
Herzog and co-authors Leila Drissi-Daoudi and Adrien Doerig take the benefits of both theories to create a new, two-stage model in which a discrete conscious percept is preceded by a long-lasting, unconscious processing period. “You need to process information continuously, but you cannot perceive it continuously.”
Imagine riding a bike. If you fell and waited every half-second to respond, there would be no way to catch yourself before hitting the ground. However, if you pair short conscious moments with longer periods of unconscious processing where the information is integrated, your mind tells you what you have perceived, and you catch yourself.
“It’s the zombie within us that drives your bike–an unconscious zombie that has excellent spatial/temporal resolution,” Herzog says. At each moment, you will not be saying to yourself, “move the bike another 5 feet.” The thoughts and surroundings are unconsciously updated, and your conscious self uses the updates to see if they make sense. If not, then you change your route.
“Conscious processing is overestimated,” he says. “You should give more weight to the dark, unconscious processing period. You just believe that you are conscious at each moment of time.”
The authors write that their two-stage model not only solves the 1,500-year-old philosophical problem but gives new freedom to scientists in different disciplines. “I think it helps people to completely fuel information processing for different prospects because they don’t need to translate it from when an object is presented directly to consciousness,” Herzog says. “Because we get this extra dimension of time to solve problems, if people take it seriously and if it is true, that could change models in neuroscience, psychology, and potentially also in computer vision.”
Though this two-stage model could add to the consciousness debate, it does leave unanswered questions such as: How are conscious moments integrated? What starts unconscious processing? And how do these periods depend on personality, stress, or disease, such as schizophrenia? “The question for what consciousness is needed and what can be done without conscious? We have no idea,” says Herzog.
Reference: “All in Good Time: Long-Lasting Postdictive Effects Reveal Discrete Perception” by Michael H. Herzog, Leila Drissi-Daoudi and Adrien Doerig, 3 September 2020, Trends in Cognitive Sciences.
This work was supported by the Swiss National Science Foundation.
Doesn’t this assume that conscious and unconscious processing can’t be happening at the same time in parallel? If so, why?
Isn’t this just a variation of what Kahneman and Tversky said with their S1/S2 model?
What then are we supposed to take from this whole idea? That this is the new “one truth”? Or is this more non-fact-based opinion that we imagine as the truth? Is this/these findings going to change perceptions for the better or worse?
It seriously adds more questions than answers.
I totally agreed with Michael Herzog. ❤❤
To me, this makes sense. And it makes sense that it might be binary. I’m stating this based on my own experiences, but all of us humans inevitably have such experiences.
Doesn’t time seem to slow down when you fall? And during that time, do you have time for any processing? No, it’s as if time moves moment by moment, like it’s sharpened to that single point. About all we can do is react after the initial thought of “I’m falling” is there. There’s no time for feelings much, either. We often end up stunned after, and only process our emotions and pain after.
And then on the flip side, during very long drives, time seems to move inconsistently. It feels so much longer going to a place, than going back. It indicates our brain is simply “skipping” some parts, replacing it with what we already know. When else does time skip? When we are asleep, passed out or under anesthesia.
If we define these time skips as unconsciousness, and the perception of every moment of consciousness, their theory makes a lot of sense, and it appears to be binary. You cannot be perceiving time moment by moment AND skipping time, after all.
I can understand from a different perspective why it seems like we may be able to do both. After all, during that car ride we are still talking to our passenger and they are responding, although we are both experiencing unconsciousness.
In such a case, I think the problem is how we define consciousness. We can say it’s awareness vs lack of awareness. But aren’t there different degrees of both? And different types. I think rather than there being one big consciousness and unconsciousness, that there are different types of being conscious and being unconscious. It, on some level, cannot be binary, because as long as we are alive, we still perceive something. Even if it is our dreams, which always seem to take place in a different time
Alternatively, I believe the authors are stating they believe it’s a off-on-off process, consciousness having many little gaps. But I don’t think that can be fully true. We tend to have emotions even when we’re not being fully conscious. Our thoughts seem to continue in a steady stream even as we’re aware of time passing. When you’re lost in thought, time passes at an accelerated speed, right? And we’re less conscious I. E. Aware.
I think this is an incomplete theory. The relationship between time and consciousness/awareness, and the lack thereof, should be studied. As well as the different types of things that cause our consciousness to be altered to different levels. Thoughts, emotions, seem to occur on a different level than process of the real world around us. That feeling of difference is, I’m certain, why many cultures believe that we have a spirit or soul that is separate from the body. I’d like to see other psychophysicists expand this theory.
A thought: in sleep our consciousness is at rest and not heightened; we are aware of our surroundings this is why we can be awakened at an unexpected sound. I am not conscious of the tree when it falls in the woods but I am aware that life in any form has movement.
Debate of 1500 years? Sounds like basic Buddhism and several other approaches to this little matter of consciousness. In many teachings the consciousness is just a 6th sense. Mostly an aggregator of news and opinion. More like a scrolling Huffington Post.
What is conciousness? Is it only when you are aware of the world or does it exist even when you are not aware. We are not aware of the world around us all the time, like when we are asleep. But when we wake up we are aware of the sleep experience. So are we conciousness during sleep? If not how do we know the sleep experience. We all look forward to a good sleep. So we must know something about that State.
This is not a 1500 year question. It has been researched by ancient sages way before 1500 years. Please look up the eastern philosophy to give you some direction and idea.Infact many eastern religions are formed on the basis of mind-conciousness relationship.
But question arises who has the experience of ” NOTHINGNESS” during the deep sleep or under anesthesia
Definitely that time something is conscious who knows there was just a void/ nothingness or “EXPERIENCE OF NO EXPERIENCE”
It’s called “subconscious”…
Conscious= when you are actively aware or things.
Unconscious= when your brain has gone into safety mode, like if you’ve just taken a severe head injury.
Subconscious= the technical processing that you don’t actively think about.
Literature geeks will flip out on you when you say someone has “unconsciously rubbed their hands, like a conniving villain”, instead of “subconsciously”.
I don’t understand how this is a scientific debate.
I’d love for the scientists and the writer of this article to talked with folks like Dr Joseph Murphy (the power of the subconscious mind) and Pete A Sanders Jr (you are psychic and free soul group, as well as worked at MIT and Caltech)
Both have fantastic views into what is conscious vs subconscious and how to tap into what we can do with the brain in either state
Both are also capable of speaking in scientific jargon as well as layman’s terms without losing or confusing the audience
I can follow either but find this article leaves too much unsaid, more like a summary to a full article…though I find that far more common in all articles over the past few years
@Ajane, this was such a well reasoned, and eloquently put response to an article about such a complex concept that I had to reply to say as much. As I read the article’s description of the study and conclusions, I found myself thinking similar things as you did, but would be hard pressed to put in such a complete way. I agree that the conscious and unconscious mind are on and off as needed, and if I had to guess as a layman in psychology, neuroscience, and evolutionary biology… it makes sense that our brains would have adapted over time to switch to unconscious processing at will in order to save energy. It is a fact that perception i.e., focus expends much more energy than normal, which is why people have a hard time doing it for long and have to train their brains to do it for extended periods.
I have no idea if this is right, but it sounds feasible to me based on my cumulative knowledge as a thinking, intellectually curious and introspective being.
[Agnosco: In a general sense I’m with Sarah on this. The subconscious ‘habit system’ controls almost all of our activities, with the conscious awareness only intervening where precedent fails to provide a ‘roadmap’, or the supervisory awareness wishes to alter conditioned habitual behavior. The incredible complexity of the functional management of a combination of the ‘simplest’ of tasks such as walking requires the application of ‘programmed sub-routines’ (learned behavior) as the conscious aspect of ourselves is quite incapable of the deliberate management of such complexity.]
Here’s an interview with Bernardo Kastrup, a scientist and philosopher (yes… 2x PhD) who has an interesting and indepth concept of what consciousness is. https://youtu.be/UPAsL0g_ydg
You would have the answers if you were ready for them. Its easy enough to find answers of any kind and yes the actual truth is here as well. You must be able to accept it and lets face it, in over 2000 years most brains haven’t changed much and that is why the answers elude you. Elevate your mind or go to church or just live rupee happy and you might find the way. Just remember to look in not go out looking.
Some comments on here are way off , it’s not easy to understand consciousness in its most basic form. If there is consciousness I don’t think it goes on and off, once conscious you remain conscious even when you’re not perceiving it. Nothingness is something, time can seem to pass at different rates but not because of consciousness. Time seems to speed up the older you get, every year is getting shorter but that’s because your not learning and seeing things for the first time, you know how things go when you’re older , when you’re young your brain is on overdrive taking everything in so time seems to slow. If anything consciousness is quantised, like tiny particles or electrons circling an atom are quantised. It is in discreet packages and we experience consciousness one pack at a time
Consciousness can only become aware of itself in the past tense. That is, consciousness must not only be able to experience reality, but it must also be able to retrieve previous experience to compare with the present experience. It is rather like having to look in a mirror to see what we look like. See: