Today, we know how Hebb’s mechanism works at the molecular level.
This quote gives the impression that there is a unitary learning mechanism at work in the brain called “Hebbian learning,” and that how it works is well understood. It is my understanding that this is not accurate.
For example, spike-timing-dependent plasticity is a Hebbian learning rule which has been postulated to underlie at least some forms of long-term potentiation and long-term depression. However, there is ongoingdebate as to how accurate/useful this concept is, including one recent attempt at a re-formulation of classical STDP.
With regard to molecular mechanisms, it was my understanding that even fundamental issues like whether LTP/LTD primarily involve presynaptic or postsynaptic modifications (or both) have not yet been cleared up.
I think your statement should be changed to something like “Though there are likely a variety of Hebbian learning mechanisms at work in the brain, neuroscientists are beginning to understand the few of them that have been discovered so far.”
Apologies for the pedantry that follows.
This quote gives the impression that there is a unitary learning mechanism at work in the brain called “Hebbian learning,” and that how it works is well understood. It is my understanding that this is not accurate.
For example, spike-timing-dependent plasticity is a Hebbian learning rule which has been postulated to underlie at least some forms of long-term potentiation and long-term depression. However, there is ongoing debate as to how accurate/useful this concept is, including one recent attempt at a re-formulation of classical STDP.
With regard to molecular mechanisms, it was my understanding that even fundamental issues like whether LTP/LTD primarily involve presynaptic or postsynaptic modifications (or both) have not yet been cleared up.
I think your statement should be changed to something like “Though there are likely a variety of Hebbian learning mechanisms at work in the brain, neuroscientists are beginning to understand the few of them that have been discovered so far.”
Agreed. Fixed. Thanks.
(But this fix introduced a grammatical error; change ‘works’ to ‘work’.)