The nature of evidence

Yes, be careful. The author of this article is careful to note that so far it's just an enhanced sensitivity:

http://phenomena.nationalgeographic...nherit-specific-memories-because-epigenetics/

Good article worth reading.

~~ Paul
Are you saying "yes, it can be called a memory?" Because as far as I can tell, they are showing that the mice react to the smell, but how would you make the leap to postulate that they do so because they have memories of being shocked when exposed to the smell? After all, automatic behaviour doesn't seem to use the same pathway which was used to learn the behaviour.

Linda
 
Offspring of odour/fear conditioned males appear to show increased behavioral sensitivity to the particular smell of either acetophenone, or propanol. That is very clear when the acetophenone, or propanol groups are compared with each other, as well as in comparison with offspring in the group who were not fear conditioned. I'd call that learning.

Anything which allows such a very particular change to appear over time must have been stored... to do so it must have been encoded... to show such specific behavioural effects in future offspring it must have been retrieved by in some way.

It's been my contention for some time, that spatial patterns store access to temporal processing. That's exactly what I think we're seeing here... and if they keep mucking around with these odour's to produce different results... the results they have got here, will probably fade away... as the processed fields begin to blur with each other and/or average themselves out.
 
Are you saying "yes, it can be called a memory?" Because as far as I can tell, they are showing that the mice react to the smell, but how would you make the leap to postulate that they do so because they have memories of being shocked when exposed to the smell? After all, automatic behaviour doesn't seem to use the same pathway which was used to learn the behaviour.
No, I'm suspicious that it is not a memory. But mostly I'm just standing by to see where this goes.

~~ Paul
 
No, I'm suspicious that it is not a memory. But mostly I'm just standing by to see where this goes.

~~ Paul
Ah, I see. Well, since the pathways used in learning can be different (and no longer necessary) from the pathways which generate the reaction to the stimuli, the presence of the reaction to the stimuli does not serve as evidence that the learning was also passed on to the mice. The two can be distinguished by the response to outcome devaluation. That is, when the shocks are attenuated or disappear, the fear reaction will decrease if learning is in use, but won't change if it is the automatic stimulus-response pathway which is in use. I think the experiment describes the latter - the F1 and F2 mice are not exposed to the outcome (shocks), yet respond to the stimulus anyways. If it was a matter of passing on the memory, they might learn faster, rather than continue to show a reaction to the stimulus in the absence of the outcome (shock). It may need a somewhat different experiment to look at whether memory can also be passed on.

Linda
 
Extinction training does not erase classically-conditioned fear memories (other than in very young rodents under 24 days old, or adult rodents if extinction occurs within a short period of time after learning, when fear memories are not yet permanent). One also needs to consider cortical mini-column spacing as even adult rodents with wide spacing appear to be unable to reverse fear memories, possibly due to the longer distance required to form new neuronal connections. This fits well with Casanova's work showing a bell shaped curve for minicolumn spacing, with dyslexics towards one end, and autistics towards the other

However in this study, the mechanism of epigenetic inheritance is completely new, and not understood, so we simply have no idea how things might work when its F0 rodents are doing the learning, and F1 and F2 rodents are being behaviorally tested.
 
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