What is “a thought”?
Can you define what a discrete “thought” is? This question was motivated by a persistent brain myth:
You have an estimated 70,000 thoughts per day.
Where did this number come from? How do you tally up 70,000 thoughts? Do some thoughts last 10 seconds, while others are finished in one tenth of a second?
Over 24 hours, one thought per second would yield 86,400 thoughts. If “thoughts” are restricted to 16 waking hours, the number would be 57,600. But we're almost certainly thinking while we're dreaming (for about two hours every night), so that would be 64,800 seconds, with an ultimate result of one thought every 0.9257 seconds, on average.
LONI®, the Laboratory of Neuroimaging at USC, included this claim on their Brain Trivia page, so perhaps it's all their fault.1
How many thoughts does the average person have per day?
*70,000
*This is still an open question (how many thoughts does the average human brain processes in 1 day). LONI faculty have done some very preliminary studies using undergraduate student volunteers and have estimated that one may expect around 60-70K thoughts per day. These results are not peer-reviewed/published. There is no generally accepted definition of what "thought" is or how it is created. In our study, we had assumed that a "thought" is a sporadic single-idea cognitive concept resulting from the act of thinking, or produced by spontaneous systems-level cognitive brain activations.
Neuroskeptic tried to find the origin of The 70,000 Thoughts Per Day Myth five years ago. He found a very bizarre post by Charlie Greer (“Helping Plumbing, HVAC, and Electrical service contractors Sell More at Higher Profits”):
Several years ago, the National Science Foundation put out some very interesting statistics. We think a thousand thoughts per hour. When we write, we think twenty-five hundred thoughts in an hour and a half. The average person thinks about twelve thousand thoughts per day. A deeper thinker, according to this report, puts forth fifty thousand thoughts daily.
If this “NSF report” exists, no one can find it (NSF is a funding agency, not a research lab). Were the LONI® researchers funded by NSF? No one knows...
via Aesthetic Machinery: The number of possible thoughts is determined by calculating
every possible pattern of brain activity.
Maybe we're approaching this in the wrong way. We shouldn't be relying on descriptions of mental events to define a thought, but rather discrete brain states.
Using this definition, “a thought” is what you can capture with your fancy new imaging technique. Therefore, a thought conveniently occupies the available temporal resolution of your method:
“A thought or a cognitive function usually lasts 30 seconds or a minute. That’s the range of what we’re hoping to be able to capture,” says Kay Tye, an assistant professor in the Department of Brain and Cognitive Sciences at MIT.
In this case, the method is FLARE, “an engineered transcription factor that drives expression of fluorescent proteins, opsins, and other genetically encoded tools only in the subset of neurons that experienced activity during a user-defined time window” (Wang et al., 2017).
But what if your method records EEG microstates, “short periods (100 ms) during which the EEG scalp topography remains quasi-stable” (Van De Ville et al., 2010). In this case, thoughts are assembled from EEG microstates:
One characteristic feature of EEG microstates is the rapid transition from one scalp field topography into another, leading to the hypothesis that they constitute the “basic building blocks of cognition” or “atoms of thought” that underlie spontaneous conscious cognitive activity.
And for good measure, studies of mind wandering, spontaneous thought, and the default mode network are flourishing. To learn more, a good place to start is Brain signatures of spontaneous thoughts, a blog post by Emilie Reas.
Source :- http://neurocritic.blogspot.in/2017/06/what-is-thought.html
