iPad Notebook export for Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts

November 3, 2018

Some quick quotes from
Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts Dehaene, Stanislas
Citation (MLA): Dehaene, Stanislas. Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts. Penguin Publishing Group, 2014. Kindle file.
that I really liked

Each short quote below is in order as it appears in book

These two anecdotes are reported by Jacques Hadamard, a world-class mathematician who dedicated a fascinating book to the mathematician’s mind.75 Hadamard deconstructed the process of mathematical discovery into four successive stages: initiation, incubation, illumination, and verification.

It is crucial to understand that, in this sort of coding scheme, the silent neurons, which do not fire, also encode information. Their muteness implicitly signals to others that their preferred feature is not present or is irrelevant to the current mental scene. A conscious content is defined just as much by its silent neurons as by its active ones.

As we discussed in Chapter 5, the prefrontal cortex, a pivotal hub of the conscious workspace, occupies a sizable portion of any primate’s brain—but in the human species, it is vastly expanded.45 Among all primates, human prefrontal neurons are the ones with the largest dendritic trees.46

One of these regions, called the frontopolar cortex, or Brodmann’s area 10, is larger in Homo sapiens than in any other ape.

Another special region is Broca’s area, the left inferior frontal region that plays a critical role in human language.

At a more microscopic level, the huge pyramidal cells in the dorsolateral prefrontal cortex (layers 2 and 3), with their extensive dendrites capable of receiving thousands of synaptic connections, are much smaller in schizophrenic patients. They exhibit fewer spines, the terminal sites of excitatory synapses whose enormous density is characteristic of the human brain. This loss of connectivity may well play a major causal role in schizophrenia. Indeed, many of the genes that are disrupted in schizophrenia affect either or both of two major molecular neurotransmission systems, the dopamine D2 and glutamate NMDA receptors,

Most interesting, perhaps, is that normal adults experience a transient schizophrenia-like psychosis when taking drugs such as phencyclidine (better known as PCP, or angel dust) and ketamine. These agents act by blocking neuronal transmission, quite specifically, at excitatory synapses of the NMDA