Tag Info

Hot answers tagged

31

The phenomenon you're talking about was a fad in the 60's, called 'interanimal memory transfer'. It started out when James McConnell performed a later-discredited experiment in which he found that if you chopped up flatworms which had been exposed to some stresses, and fed them to other unexposed flatworms, the unexposed worms became wary of the source of ...


23

Unfortunately, we are all still "confuzzled" by how memory works. We are far from a complete understanding of how memory is stored and recalled. Nonetheless, we do know a little, so read on. Your understanding of basic neural function is almost correct. First, an individual neuron will signal through its single axon onto the dendrites of many downstream ...


10

Answer The mechanism for salmon natal homing isn't exactly known, but there are really two good hypotheses out there. Salmon have an extremely good sense of smell. One hypothesis is that they retain an imprint of their birthplace's odor, and manage to recognize it again at a later time (as explained by this article). Another hypothesis: the Earth's ...


8

Surely a important question. But there are different kinds of memory (classified mainly as declarative and procedural) which you don't specify exactly in your question. Wikipedia and Scholarpedia list here many known facts. I will give you some short hints and links for introduction and overview instead of pasting that stuff here. You are probably ...


6

The idea that memories could be stored as RNA or proteins is an old one. It got a lot of attention decades ago when James McConnell did a number of experiments where he conditioned planarian flatworms to respond to certain stimuli, ground them up, fed them to worms that hadn't gone through the conditioning. He claimed to have observed that the worms fed ...


6

The current working theory (note this is still an open question, but there are many leads being followed): Sensory systems receive a combination of signals from an event, which are initially bound to the hippocampus (this is called episodic memory). Then, typically during sleep, the memories are consolidated. A simplified view is that consolidation ...


6

I would like to point out some ways your understanding is wrong. "Neural networks" are usually a computer science term, only very, very loosely based on actual neural networks. The idea of layers in a neural network is pretty much an invention of computer science, it doesn't really reflect the reality. Also, neurons are not binary switches. It isn't so much ...


6

Three possible mechanisms are mentioned in the first referenced article [1]: Attentional blink - the failure to detect a (visual) stimulus [2]. Visual short-term memory - non-permanent storage of visual information over an extended period of time [3]. Psychological refractory period - the period of time during which the response to a second stimulus is ...


5

It's very likely that memory is "lossy" and holographic, such that you can keep adding more information indefinitely, but retain it with less and less accuracy. Memory isn't a digital storage system with X gigabytes of capacity, and the inputs to memory aren't neat little packets. What we remember are a web of associations and patterns. Vastly ...


3

There are multiple levels of memory, some of which would die immediately, some of which would take some time. So the answer is: it depends; some immediately, some only very slowly. At the highest level, the current neuronal firing state of the brain encodes memory on a very short scale - working memory. The memory held on this level does not have a clear ...


3

Is there clear evidence that LTP is involved in long-term memory (not counting 1 hour as long-term...)? Has LTP/LTD been shown in vivo after long period of time (e.g. months). This Journal of Neuroscience paper shows LTP in vivo measured out to one year: Abraham WC, Logan B, Greenwood JM, Dragunow M. 2002. Induction and experience-dependent ...


3

This is somewhat unrelated, and for that, I apologize, but I find it truly fascinating, and I believe you will too. Zebra finches are a song bird that have become a popular model organism for behavioral research. They have a very stereotypical pattern for song learning: at about 70 days after hatching, the baby male song bird starts to listen to his ...


2

Really good questions. As the guy who brought up LTP/LTD in the question you referenced, I thought I would weigh in. There is the traditional definition of LTP/LTD as an increased/decreased synaptic efficacy at a single synapse or in a single cell. As you've noted, this is unlikely to be the only phenomena underlying memory and sometimes it's hard to see ...


2

Good questions. I don't think that LTP has been (or will be) shown to be THE mechanism for long term memory. It is one of many mechanisms, all with different time courses, that contribute to the modification of synaptic efficiencies. One mechanism not mentioned much anymore, but which I feel is absolutely crucial, is dendritic spine growth. Spines are ...


2

We don't have large memory capacities. If anything I would have asked the opposite, why is our memory so bad and unreliable considering how large our brains are. Even with this gigantic brain we struggle to remember a few phone numbers. Here's how our short term memory compares to monkeys: https://www.youtube.com/watch?v=zJAH4ZJBiN8. I have no explanation ...


2

Although there is clearly no feasible mechanism for such a phenomenon, there is good evidence that transplant patients can believe in some sort of transference of qualities from the donor. See for example (my emphasis): Inspector, Y. et al. (2004) Another Person's Heart: Magical and Rational Thinking in the Psychological Adaptation to Heart ...


2

There seems to be no effect of vitamins. This paper ("Preventing cognitive decline in healthy older adults." found no evidence for herbal supplements, vitamins or fatty acids improve cognitive functions. There seems to be some evidence ("Preventing Alzheimer's disease-related gray matter atrophy by B-vitamin treatment.") that a cocktail of hig dosed ...


2

This question is more of a medical question than one of the underlying mechanisms of biological function. The formation of long term memories is related to long-term potentiation. There are multiple neurotransmitters involved in this process. Ethanol primarily affects NMDA receptors. Drugs used to specifically induce anterograde amnesia, like propofol, ...


1

Forgetfulness is a common phenomenon that tends to increase with age. It usually affects short term memories but it can affect long term ones too. Here are some possible causes which I quote from Healthline (the full list available at that link): sleep deprivation use of alcohol or drugs and some prescription medications lack of oxygen to the ...


1

Once the thermodynamically irreversible processes we call brain-death have occurred both memories and the machinery to retrieve them are lost. This is not an answer but a cavil with the premise of the question. Challenges that do not destroy the brain itself are different from those that do. In particular there may be a big difference between hypoxia ...


1

Scents can make memory recalls. We experience this very often, like when we repeatedly smell a good perfume in ,say a shopping mall , and when some person uses it too, we recall the memory of the shopping mall. This hqppens especially when the smell is associated with a very good or very bad incident. For an experiment, you can expose yourself or someone to ...


1

My understanding is that there are two major reasons for not being able to recall where your socks are or when your anniversary is: The information was not committed to short term memory in the first place when you initially encountered it, so there was never anything to remember. The information is intact, but you are not able to effectively retrieve it, ...


1

Discrete data must be stored in low entropy structures in the brain that over time spontaneously shift to a higher entropy state How on Earth could you possibly know that? You are overextending physics to the workings of the brain and there is nothing that says this is necessarily so. Memory decay is not fully understood but it is known that the more ...


1

Interesting point, but I think there is a simpler and possibly more widespread reason for the decay of memories. Namely, as new memories need to be stored in the same neural networks, the weights, timings and other properties of the network links are constantly changed. In other words, there is competition for the limited amount of memory. This re-use of the ...


1

There have been quite a few studies on stimulating the brain with electrical pulses and it has been found to be successful too. Three papers of particular interest I found were: 1) In a study titled "Explaining How Brain Stimulation Can Evoke Memories", it was found that electrical stimulation in the temporal neocortex can cause neurosurgical patients to ...


1

Scientists say that people can have multiple dreams every night and the ones that are not very significant are easily forgotten. Only those experiences that elicit an emotional response (happy, frightened) seem to stick in memory. Suggestions have also been made that being anxious or depressed makes our dreams stick to memory too (reference). A study ...


1

I can make a rough analogy in terms of digital media storage. Our memories exist as a relationship between our perceptions and our sensations. Computers store input readily. However, humans store memories perceptually. This means who we are and how we remember an event permanently changes our recollection. If you look at the progression of lossy video ...



Only top voted, non community-wiki answers of a minimum length are eligible