It is impossible to exactly define what intelligence would be in a molecule or complex molecular system. The Turing test is used to determine if a machine can match the intelligence of humans, but is inexact. Can we think of a version of a Turing test to consider if hepatitis D virus, the smallest human virus, is intelligent. For the details of hepatitis D virus' very complex lifestyle please refer to the previous post Smallest Human Virus – Very Dangerous, Very Intelligent

In 1972, a British pharmacologist named Geoffrey Burnstock published a paper proposing that ATP is released from nerve terminals and acts as a neurotransmitter. The scientific establishment's response was a dismissal. The objections were that as the universal energy currency of all living cells, ATP was too ubiquitous to serve as a signal among neurons––it was everywhere, inside everything. That skepticism delayed a medical revolution by two decades. Burnstock continued wor

For more than a century, neuroscience has been built around a neuron-centered worldview. The heroes of this story are familiar neurotransmitters: dopamine, serotonin, norepinephrine, acetylcholine, glutamate, and GABA. Textbooks describe neurons communicating across synapses in brain circuits using these specialized chemical messengers. The vast ‘connectome’ network of axons and dendrites was believed to determine mental events. Neurons were viewed as the only true informatio

Infants born without a cerebral cortex demonstrate that they still have a variety of conscious experiences.

Alternative splicing of messenger RNA has been shown to be critical for the development of the human brain. The ability to make many new and complex proteins allowed the development of the enormous molecular complexity in different neurons and in different regions. For some reason, in evolution humans developed the ability to use alternative splicing much more than other species. This ability is most prominent in the brain. This post updates the most recent understanding of h

With each mental event, dramatic structural changes occur inside large numbers of neurons, outside of neurons in the extracellular space, at the synapses between neurons and in glial brain cells. Remarkably, these molecular changes occur instantaneously all over the brain in specific circuits using many different mechanisms (some have been described in previous posts). For each different momentary event, the same neuron can be used in completely different circuits. Signals in

A thought ……. Suddenly, new synapses Learning a fact ……. Suddenly, a new brain cell in the hippocampus…. … Axons are built, axons are pruned. How does the brain know how to do this? How does neuroplasticity work? Learning stimulates new brain cells. Mental events instantly affect changes in dendrites and synapses. The brain noticeably changes shape with attention, meditation, exercise, diet, and habits of life.The active brain does much more. It changes its function when it

The regulation of DNA is fantastically complex with many different layers: changing 3D shapes of the chromatin and loops of DNA; regional differences in nuclear DNA; large numbers of different epigenetic tags on DNA nucleotides and protective protein histone molecules; complex DNA repair mechanisms and alternative messenger RNA splicing; hundreds of thousands of transcription factors; and many different kinds of small and large RNAs that influence every aspect of the process.

As more animals are found to have advanced cognitive ability, it is clear that the human brain is not the model for all advanced abilities. There are animals that have greater capacities; and those with similar capacities can use very different brain structures. Intelligence evolved a number of different ways. Last week 28 studies revealed unprecedented detail about the songbird’s brain. They, for the first time, compared vocal learning similarities in songbirds and humans. T