If Spaun as it is now really does work “just like a human”, then building a human-level AI is just a matter of speeding it up.
As I explained in this comment, Spaun can only perform tasks that are specifically and manually programmed into it. It is very, very far from working just like a human. It’s definitely incapable of learning new skills or concepts, for example. What the original article said was:
They say Spaun can shift from task to task, “just like the human brain,” recognizing an object one moment and memorizing a list of numbers the next.
Well gosh, my desktop computer can also shift from task to task, just like the human brain, mining bitcoins one moment and decoding MPEGs the next. This is either PR or (perhaps unintentional) hype by the reporter, saying something that is literally true but gives the impression of much greater accomplishment.
(Which isn’t to say that Spaun might not continue with or inspire further more interesting developments, but a lot of people seem to be overly impressed with it in its current state.)
Hi, it’s Terry again (one of the researchers on the project)
The interesting thing (for me) isn’t that it can shift from task to task, but that it can shift from task to task just like the human brain. In other words, we’re showing how a realistic neural system can shift between tasks. That’s something that’s not found in other neural models, where you tend to either have it do one task or you have external (non-neural) systems modify the model for different tasks. We’re showing a way of doing that selecting routing and control in an entirely neural way that maps nicely onto the cortex-basal ganglia-thalamus loop.
Oh, and, since we constrain the model with a bunch of physical parameters influencing the timing of the system (reabsorption of neurotransmitter, mostly), we can also look at how long it takes the system to switch tasks, and compare that to human brains. It’s these sorts of comparisons that let us use this sort of model to test hypotheses about what different parts of the brain are doing.
According to my understanding, Spaun is only able to shift between a fixed set of tasks, and according to a fixed algorithm (if the first two inputs are “A1”, route the information one way so that it ends up doing one task, and if the first inputs are “A2“, route the information another way, etc.) that was manually designed. You haven’t explained yet (or emulated) how human brains are able to switch fluidly between an ever changing set of possibe tasks, and without having to be prompted by specific codes such as “A1” and “A2”.
If my understanding is correct, I think a clearer and fairer description of your accomplishment might be that you’ve demonstrated task shifting “on a (simulated) neural substrate that is structually similar to the human brain”, rather than task shifting “just like the human brain”.
Yup, I’d say that’s a fair way of expressing it, although I think we take “neural substrate that is structurally similar to the human brain” much more seriously than other people that use phrases like that. It’s a similar enough substrate that if fixes a lot of our parameter values for us, leaving us less open to “fiddle with parameters until it works”.
We’ve also tried to make sure to highlight that it can’t learn new tasks, so it’s not able to work in the fluid domains people do. It also doesn’t have any intrinsic motivation to do that switching.
Interestingly, there are starting to be good non-neural theories of human task switching (e.g. [http://act-r.psy.cmu.edu/publications/pubinfo.php?id=831] ). These are exactly the sorts of theories we want to take a close look at and see how they could be realistically implemented in spiking neurons.
As I explained in this comment, Spaun can only perform tasks that are specifically and manually programmed into it. It is very, very far from working just like a human. It’s definitely incapable of learning new skills or concepts, for example. What the original article said was:
Well gosh, my desktop computer can also shift from task to task, just like the human brain, mining bitcoins one moment and decoding MPEGs the next. This is either PR or (perhaps unintentional) hype by the reporter, saying something that is literally true but gives the impression of much greater accomplishment.
(Which isn’t to say that Spaun might not continue with or inspire further more interesting developments, but a lot of people seem to be overly impressed with it in its current state.)
Hi, it’s Terry again (one of the researchers on the project)
The interesting thing (for me) isn’t that it can shift from task to task, but that it can shift from task to task just like the human brain. In other words, we’re showing how a realistic neural system can shift between tasks. That’s something that’s not found in other neural models, where you tend to either have it do one task or you have external (non-neural) systems modify the model for different tasks. We’re showing a way of doing that selecting routing and control in an entirely neural way that maps nicely onto the cortex-basal ganglia-thalamus loop.
Oh, and, since we constrain the model with a bunch of physical parameters influencing the timing of the system (reabsorption of neurotransmitter, mostly), we can also look at how long it takes the system to switch tasks, and compare that to human brains. It’s these sorts of comparisons that let us use this sort of model to test hypotheses about what different parts of the brain are doing.
According to my understanding, Spaun is only able to shift between a fixed set of tasks, and according to a fixed algorithm (if the first two inputs are “A1”, route the information one way so that it ends up doing one task, and if the first inputs are “A2“, route the information another way, etc.) that was manually designed. You haven’t explained yet (or emulated) how human brains are able to switch fluidly between an ever changing set of possibe tasks, and without having to be prompted by specific codes such as “A1” and “A2”.
If my understanding is correct, I think a clearer and fairer description of your accomplishment might be that you’ve demonstrated task shifting “on a (simulated) neural substrate that is structually similar to the human brain”, rather than task shifting “just like the human brain”.
Yup, I’d say that’s a fair way of expressing it, although I think we take “neural substrate that is structurally similar to the human brain” much more seriously than other people that use phrases like that. It’s a similar enough substrate that if fixes a lot of our parameter values for us, leaving us less open to “fiddle with parameters until it works”.
We’ve also tried to make sure to highlight that it can’t learn new tasks, so it’s not able to work in the fluid domains people do. It also doesn’t have any intrinsic motivation to do that switching.
Interestingly, there are starting to be good non-neural theories of human task switching (e.g. [http://act-r.psy.cmu.edu/publications/pubinfo.php?id=831] ). These are exactly the sorts of theories we want to take a close look at and see how they could be realistically implemented in spiking neurons.