The Number of Neurons in the Brain: How We Report What We Do Not Know

Abstract

binations of actions and consequences that could not be described by the consequence grid. None exist. The four quadrants of the matrix can then be labeled by students, with each quadrant having a unique label. Students realize that the quadrant labeled negative reinforcement cannot, at the same time, be labeled punishment.A second remedy is to present several examples to illustrate that trying to distinguish instances of punishment and negative reinforcement sometimes results in ambiguous situations. For instance, "Because you talked back, you will have to stay after school," and "You will have to stay after school until you clean your desk," represent ~unishment and negative reinforcement statements, respectively. In the first statement, an aversive stimulus (staying after school) is being applied in order to decrease an unwanted behavior. In the second statement, an aversive stimulus (staying after school) is being removed in order to increase a desired behavior.As a third remedy, distribute teacher-prepared examples of each consequence. Ask students to label each consequence by identifying whether something desired or dreaded is being applied or removed. After students have mastered this activity, have them create their own examples, exchange them, and then evaluate each other's work.The remaining three remedies do not deal directly with teaching the concept of negative reinforcement. However, they do call attention to problems that interfere with learning the concept of negative reinforcement.As a fourth remedy, indicate that part of the confusion over negative reinforcement concerns the connotative meaning of the word negative. Too often people forget that the word negative in negative reinforcement simply indicates an action, not a value judgment. Positive refers to supplying something; negative refers to removing something. Students overlook the fact that both positive reinforcement and negative reinforcement contain the key word reinforcementsomething to which most people look forward.How far we go to avoid dealing with anything negative, including negative numbers, is highlighted in the familiar example of Scholastic Aptitude Test (SAT) scores. In reality, SAT scores are simply 9-scores with a mean of zero, a standard deviation of 1, and a range from -3 to +3. Imagine the panic if students earned SAT scores of -.3, -.5, or -1.6. Of course, when the negative sign and the decimal are removed by multiplying by 100 and then adding 500, one obtains the more recognizable and less threatening scores of 470, 450, and 340, respectively.Mention to students the relatively infrequent appearance of negative reinforcement in the literature as the basis for a fifth remedy. T o demonstrate that they have fewer opportunities to learn about this concept, you might have students review three common indexes, Psychological Abstracts, the Educational Resources Information Center's (ERIC) Resources in Education (RIE), and Current Index to Journals in Education (CIJE). Have them count the number of citations for negative reinf...

How many neurons do you have? Some dogmas of quantitative neuroscience under revision

“…Second dogma -the human brain has one hundred billion neurons and 10 times more glial cells 'The mature brain is composed of 100 billion to 200 billion neurons and perhaps 10 times as many glial cells' (Hubel, 1979) The 'magic number' of 100 billion neurons in the human brain has been widely sustained in papers (Hubel, 1979;Fischbach, 1992;Noctor et al, 2007) and textbooks (Kandel et al, 2000;Bear et al, 2007;Purves et al, 2008), although a broad range is arbitrarily adopted, from 10 billion to 1 trillion (reviewed by Soper & Rosenthal, 1988). However, little direct evidence for it has been produced.…”

“…For glial cells, the prevalent dogma poses that the glia ⁄ neuron ratio is approximately 10 : 1 in the brain (Hubel, 1979;Nauta & Feirtag, 1986;Soper & Rosenthal, 1988;Nishiyama et al, 2005;reviewed by Hilgetag & Barbas, 2009). However, with the isotropic fractionator, the actual glia ⁄ neuron ratio for the whole human brain was shown to be close to 1 (Fig.…”

“…, 2007; Purves et al. , 2008), although a broad range is arbitrarily adopted, from 10 billion to 1 trillion (reviewed by Soper & Rosenthal, 1988). However, little direct evidence for it has been produced.…”

The search for true numbers of neurons and glial cells in the human brain: A review of 150 years of cell counting

“…There was a disconnect between published reports on actual counts of cells in the human brain, and how such numbers were reported in review articles and text books. Inconsistencies in reports of neuron content in the human brain were first documented for psychology textbooks and reviews in the 1980s (Soper and Rosenthal, ). We here provide a similar analysis for neuroscience reviews and textbooks, but we compile, besides neuron counts, also reports about glia counts and the GNR, and add trends and insights from a more longitudinal, long‐term perspective over several decades.…”

Belief when evidence does not support theory

“…Or, perhaps, because Maslow's theory makes so much sense and is so attractive, empirical evidence is not needed? Is Maslow's theory an example of what some have called the lore of a discipline, something handed down from one writer to another without adequate scientific confirmation (Soper & Rosenthal, 1988)?…”