Why Gender Matters


What Parents and Teachers Need to Know about the Emerging Science of Sex Differences

My main motivation for writing Why Gender Matters was to make sense of what I had been seeing in my own clinical practice, as a board-certified family doctor – and as a PhD psychologist – among the children who I had come to known, practicing for many years in the same town in Montgomery County, Maryland. I tried to make sense of these observations by linking them to emerging research in psychology and neuroscience. Some of those efforts were more successful than others. On this Web page, I would like to provide updates and corrections for those points where my discussion in Why Gender Matters is now clearly out-of-date or inaccurate.

  • “Until recently, there have been two groups of people: those who argue sex differences are innate and should be embraced and those who insist that they are learned and should be eliminated by changing the environment. Sax is one of the few in the middle — convinced that boys and girls are innately different and that we must change the environment so differences don’t become limitations.”

    – TIME Magazine, cover story (view article)

  • “… a lucid guide to male and female brain differences…”

    – The New York Times (view article)

  • Using studies as well as anecdotes from his practice and visits to classrooms, [Sax] offers advice on such topics as preventing drug abuse and motivating students. . . . The book is thought-provoking, and Sax explains well the science behind his assertions”

    — Scientific American Mind (view article)

Chapter Updates

Chapter 2: female/male differences in VISION. The reality I was trying to understand in this section of chapter 2 is the fact that when you give young children a blank sheet of paper and a box of crayons, most girls draw people, pets, flowers and/or trees. Most boys try to draw a scene of action at a moment of dynamic change. That’s a robust empirical finding, valid across race, ethnicity, and socioeconomic status. That doesn’t mean that ALL boys try to draw a scene of action; some boys draw exactly what the girls draw. But boys are more likely to draw a scene of action, such as a monster attacking an alien; girls are more likely to draw people, pets, flowers, or trees, with lots of colors. The people in the girls’ pictures usually have faces, eyes, hair, and clothes; the people in the boys’ pictures (if there are any people) often are lacking hair, clothes, often the boys draw mere stick figures in one color. How come? The usual answer “Because that’s what we teach them to do” is unpersuasive, as I explain in Why Gender Matters. On the contrary, many of these boys insist on drawing these pictures not because teachers tell them to draw such pictures, but in spite of the teacher’s repeated pleas, “Why do you have to draw such violent pictures? Why can’t you draw something nice – like what Emily drew?”

But my discussion here falters when I try to link this research to female/male differences in the retina of the rat. For a much better discussion of this topic — female/male differences in VISION — please see chapter 5 of my third book, Girls on the Edge, especially the sections “All our girls love physics” beginning on p. 132, “Would you rather play with a truck or a doll?” on p. 134, and “Monkeys, girls, boys, and toys” on p. 136, where I share Professor Gerianne Alexander’s hypothesis regarding female/male differences in the “P system” and the “M system” in the human visual system. You will also find much stronger scholarly support provided in chapter 5 of Girls on the Edge than I provided in chapter 2 of Why Gender Matters. In my defense, many of the key articles I cited in 2010 in Girls on the Edge – such as Kim Wallen’s work on female/male differences in the toy preferences of monkeys, or Katrin Amunt’s work on female/male differences in human visual cortex – had not been published when Why Gender Matters was published in 2005.

Chapter 2: female/male differences in HEARING. The reality I was trying to understand in this section of chapter 2 was my own repeated observation, over many years of clinical practice, that some young boys who had been diagnosed by other practitioners as having ADHD, suddenly did much better in the classroom, and no longer needed to be on medication, simply by moving them to a classroom with a teacher who spoke more loudly – about 8 decibels more loudly. It was much less common to find a same-age girl who did much better in a classroom where the teacher spoke more loudly. So far so good. I tried to explain this observation with reference to female/male differences in threshold auditory acuity. That was simply a mistake on my part. Female/male differences in threshold auditory acuity 1) are pretty much irrelevant to any observation regarding supra-threshold stimuli, and 2) are much too small to account for the observation that these boys benefited when teachers spoke about 8 to 10 dB more loudly. Female/male differences in threshold auditory acuity – comparing girls and boys the same age – are only on the order of 3 dB or less, usually less.

In my defense, two of the key papers which lead to the correct explanation of this phenomenon – by Professor Ken Norwich and his colleagues at the University of Toronto – were only published in 2007 and 2009, respectively. Why Gender Matterswas published in February 2005. For an updated and far more accurate explanation of why SOME boys need teachers to speak more loudly in the classroom, please read my October 2010 article entitled Sex differences in hearing, which you can download in full as a PDF, along with two scholarly supplements not found in the print edition. My October 2010 article greatly expands, updates, and corrects my discussion of this topic in chapter 2 of Why Gender Matters.

Chapter 5: female/male differences in mathematics instruction. The reality I was trying to understand in this section of chapter 5 is the fact that many middle-school boys seem to learn algebra better when you start with numbers, whereas many same-age girls seem to be more engaged if you start with a word problem. For example, if you are teaching equations in multiple variables, the typical 7th-grade boy will do better if you begin by asking “If x + 2y = 60, and 2x + y = 90, how do we solve for x and y?” But the typical 7th-grade girl will be more engaged if you begin by asking “If a sweater and two blouses cost 0, and two sweaters and a blouse cost $90, how much does each blouse and each sweater cost?” That is true even if the girl happens to hate shopping. This finding is equally valid whether you are in Pittsburgh PA or Perth WA (Western Australia); it is valid whether the students are affluent or low-income; it is valid whether the students are Black or White, etc. Again, I’m not suggesting that EVERY boy does better with equations than with word problems; that is certainly not true. But the TYPICAL boy does better with equations than with word problems, whereas many girls are more engaged if you begin with the word problem and then work your way back to the equation. So far so good. The problem is that I tried to ‘explain’ that finding by referring to a study of spatial navigation in German college students. That study isn’t really relevant, 1) because spatial navigation is not the same task as algebraic problem-solving, and 2) because students at university are many years older than students in middle school. The problem is that we didn’t have a functional MRI study of middle-school-age girls and boys doing algebra problems – and we still have no such study. We do now have one study, by Katherine Keller and Vinod Menon of Stanford University, published in the journal Neuroimage, which shows striking female/male differences in brain regions activated during arithmetic computation – but the subjects are adults (mean age 24 years), not adolescents, and one of the major points I emphasize in Why Gender Matters and elsewhere is that what’s true for adults may not be true for 13-year-olds. You may download the full text of the Keller/Menon study, at no charge, by clicking on “Gender Differences in the Functional and Structural Neuroanatomy of Mathematical Cognition“.

[/cbp_widget_element][/cbp_widget_box][/cbp_widget_row][/cbp]0, and two sweaters and a blouse cost $90, how much does each blouse and each sweater cost?” That is true even if the girl happens to hate shopping. This finding is equally valid whether you are in Pittsburgh PA or Perth WA (Western Australia); it is valid whether the students are affluent or low-income; it is valid whether the students are Black or White, etc. Again, I’m not suggesting that EVERY boy does better with equations than with word problems; that is certainly not true. But the TYPICAL boy does better with equations than with word problems, whereas many girls are more engaged if you begin with the word problem and then work your way back to the equation. So far so good. The problem is that I tried to ‘explain’ that finding by referring to a study of spatial navigation in German college students. That study isn’t really relevant, 1) because spatial navigation is not the same task as algebraic problem-solving, and 2) because students at university are many years older than students in middle school. The problem is that we didn’t have a functional MRI study of middle-school-age girls and boys doing algebra problems – and we still have no such study. We do now have one study, by Katherine Keller and Vinod Menon of Stanford University, published in the journal Neuroimage, which shows striking female/male differences in brain regions activated during arithmetic computation – but the subjects are adults (mean age 24 years), not adolescents, and one of the major points I emphasize in Why Gender Matters and elsewhere is that what’s true for adults may not be true for 13-year-olds. You may download the full text of the Keller/Menon study, at no charge, by clicking on “Gender Differences in the Functional and Structural Neuroanatomy of Mathematical Cognition“.

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