In his famous book, The Origin of Consciousness in the Breakdown of the Bicameral Mind, Julian Jaynes mentions his experiments on learning in mimosa plants. I found this fascinating and always wish he had provided more detail. Now a paper published in Nature points to evidence that plants are capable of associative learning. From the abstract:
Here we show that this type of learning occurs in the garden pea, Pisum sativum. By using a Y-maze task, we show that the position of a neutral cue, predicting the location of a light source, affected the direction of plant growth. This learned behaviour prevailed over innate phototropism. Notably, learning was successful only when it occurred during the subjective day, suggesting that behavioural performance is regulated by metabolic demands. Our results show that associative learning is an essential component of plant behaviour. We conclude that associative learning represents a universal adaptive mechanism shared by both animals and plants.
I just came across this review of my book. Many thanks to The Art of Memory.
There is also a lengthy summary in the comments.
Here is a first letter mnemonic for the potentially useful task of learning the Dewey Decimal System:
Generally, philosophical religionists see language scientifically to favor literary history.
|Philosophy and psychology
Adapted from Evans (2007)
Methylene blue is a chemical that has been used an antidote for cyanide poisoning. There have been suggestions over the years that it may have an effect on memory. A paper titled “Multimodal Randomized Functional MR Imaging of the Effects of Methylene Blue in the Human Brain,” was recently published in the journal Radiology. Unfortunately, I have not been able to locate a copy of the original paper, so I am forced to rely on this account in ScienceDaily:
“A single oral dose of methylene blue results in an increased MRI-based response in brain areas that control short-term memory and attention, according to a new study. Methylene blue was associated with a 7 percent increase in correct responses during memory retrieval.”
Several media outlets report that methylene blue was shown to improve short term memory. This is one of the reasons I need to see the original paper. The phrase “short term memory” is used differently by psychologists than the general public. Indeed, many psychologists have abandoned the phrase altogether and, instead, talk about working-memory. When non-academics talk about short term memory they mean things like forgetting a phone number or someone’s name. In fact, most of these are failures of attention or long term memory, not problems with short term memory. Thus, I worry that reporting on this research may be very misleading.
A paper in the journal Cell Metabolism offers another explanation for the postive effect of exercise on memory:
“Here, we show that a muscle secretory factor, cathepsin B (CTSB) protein, is important for the cognitive and neurogenic benefits of running.”
Here is a journalistic summary:
“Working out is good for the brain. Now, a team of scientists from the U.S. and Germany has a clearer idea why. A protein called cathepsin B, produced and secreted by muscle during exercise, is required for exercise-induced memory improvement and brain cell production in mice, the scientists reported in Cell Metabolism today (June 23). They also showed that levels of cathepsin B are positively correlated with fitness and memory in humans”
Science Daily has the details:
“Their research has shown that new brain cells, or neurons, can be formed by stimulating the front part of the brain which is involved in memory retention using minute amounts of electricity.
The increase in brain cells reduces anxiety and depression, and promotes improved learning, and boosts overall memory formation and retention.
The research findings open new opportunities for developing novel treatment solutions for patients suffering from memory loss due to dementia-related conditions such as Alzheimer’s and even Parkinson’s disease.”
You can find the original paper here. From the paper:
“Overall, these findings suggest that chronic ventromedial prefrontal cortex high-frequency stimulation may serve as a novel effective therapeutic target for dementia-related disorders.”
An interesting piece in Quanta Magazine on sharp-wave ripples, a pattern of brain wave activity that occurs during sleep.
“Over the past few decades, researchers have worked to uncover the details of how the brain organizes memories. Much remains a mystery, but scientists have identified a key event: the formation of an intense brain wave called a “sharp-wave ripple” (SWR). This process is the brain’s version of an instant replay — a sped-up version of the neural activity that occurred during a recent experience. These ripples are a strikingly synchronous neural symphony, the product of tens of thousands of cells firing over just 100 milliseconds. Any more activity than that could trigger a seizure.”
Here is report from the Society for Neuroscience meeting where sharp-wave ripples are explained: