Dopamine is not the feel good molecule or the basis of pleasure. The idea that any molecule considered in isolation could be the basis of a subjective experience is basically nonsense.
For people who can’t really reason through this idea, there is plenty of experimental evidence showing the complexity of each and every “celebrity” neurochemical — dopamine, serotonin, oxytocin, and so on.
I was asked this question on Quora.
We don’t really know. But as one of my professors once said half-jokingly, “the brain is a bag of tricks”. There is no reason to assume that all brain regions use the same coding scheme.
Here are some basic concepts that guide how neuroscientists think about information in the brain:
I was asked this question on Quora:
Can you explain to a layman what neuroplasticity entails?
Neuroplasticity is the umbrella term for all of the brain’s mechanisms for learning and memory.
Since the average layperson already knows about learning and memory, I’m not sure whether there are any interesting implications.
Unless of course you are surprised that the brain is involved in learning and memory. Then the implications are vast. 🙂
I was asked the following question on Quora.
“Are specific memories just arrangements of atoms in our brains? Could you put certain molecules in someones head and give them an exact memory that you had?“
Short answer: No.
Modern science has shown that every thing is an arrangement of atoms: neurons, apples, tables, rockets, asteroids, aardvarks… they are all made up of atoms.
The question now is this: is a memory a thing?
This answer was written in response to the following Quora question:
New research has found no neurogenesis in human adults, could this mean there is none or could it mean that neural stem cells are undetectable with the used techniques? What are your thoughts on this?
It’s good that you’re thinking of such things, since that is exactly what researchers themselves have to do, and what reviewers do. In order to show that the method works, there have to be adequate controls as part of the experiment.
And this is in fact the case. The paper would not have been published without controls.
A new study suggests that new neurons are not born very often in human adults.
Birth of New Neurons in the Human Hippocampus Ends in Childhood
“The lab’s new research, based on careful analysis of 59 samples of human hippocampus from UCSF and collaborators around the world, suggests new neurons may not be born in the adult human brain at all. The findings present a challenge to a large body of research which has proposed that boosting the birth of new neurons could help to treat brain diseases such as Alzheimer’s disease and depression. But the authors said it also opens the door to exciting new questions about how the human brain learns and adapts without a supply of new neurons, as in seen in mice and other animals.”
My labmates are all monkey neuroanatomists, and for years they have been skeptical about the neurogenesis narrative, particularly in primates. Another famous dissenter is Pasko Rakic. Read about his complaints in this Guardian article from 2012:
Does your brain produce new cells?
I am currently reading an excellent paper that will be published in Behavioral and Brain Sciences soon. It raises some very important issues with popular conceptions of mental illness.
Brain disorders? Not really… Why network structures block reductionism in psychopathology research
These two figures capture some of the key points:
Here is the abstract:
“In the past decades, reductionism has dominated both research directions and funding policies in clinical psychology and psychiatry. However, the intense search for the biological basis of mental disorders has not resulted in conclusive reductionist explanations of psychopathology. Recently, network models have been proposed as an alternative framework for the analysis of mental disorders, in which mental disorders arise from the causal interplay between symptoms. In this paper, we show that this conceptualization can help understand why reductionist approaches in psychiatry and clinical psychology are on the wrong track. First, symptom networks preclude the identification of a common cause of symptomatology with a neurobiological condition, because in symptom networks there is no such common cause. Second, symptom network relations depend on the content of mental states and as such feature intentionality. Third, the strength of network relations is highly likely to partially depend on cultural and historical contexts as well as external mechanisms in the environment. Taken together, these properties suggest that, if mental disorders are indeed networks of causally related symptoms, reductionist accounts cannot achieve the level of success associated with reductionist disease models in modern medicine. As an alternative strategy, we propose to interpret network structures in terms of D. C. Dennett’s (1987) notion of real patterns, and suggest that, instead of being reducible to a biological basis, mental disorders feature biological and psychological factors that are deeply intertwined in feedback loops. This suggests that neither psychological nor biological levels can claim causal or explanatory priority, and that a holistic research strategy is necessary for progress in the study of mental disorders.”
Behavioral and Brain Sciences is one of the premier journals for “big thinking” in cognitive science and neuroscience, so it’s great to see these ideas there.
I was asked the following question on Quora:
Why can’t we see, touch, hear and smell on a cellular level? And what happens if we can?
Here’s what I wrote:
Essentially, we perceive the visible world in the way that we do because of our overall size, the shape of our eyes, and the sizes of objects in the world that are relevant to our voluntary behavior.
This question might seem silly, but a closely related question can serve as a springboard for us to think very deeply about physical scale, and how it relates to biological life and to the very concept of a scientific law.
But first lets deal with the basic question.
Just saw this on twitter:
Here’s the link to the (thus far unreviewed!) study:
How much does education improve intelligence? A meta-analysis
“… we found consistent evidence for beneficial effects of education on cognitive abilities, of approximately 1 to 5 IQ points for an additional year of education. Moderator analyses indicated that the effects persisted across the lifespan, and were present on all broad categories of cognitive ability studied. Education appears to be the most consistent, robust, and durable method yet to be identified for raising intelligence.”