Sex Differences

1. Sex Differences Authors By Lee Ellis, Scott L. Hershberger, Evelyn M. Field, Scott Wersinger, Sergio Pellis, Amir Hetsroni, David Geary, By: Sophie Loyd & Erin Rementer

2. Brain and Biochemistry Introduction • Brain Size Differences • - Male brains are generally larger then female brains. • - On average, a male adult brain is 11% larger than a female adult brain • - Corpus Callosum • o Women are said to have larger and more developed corpus callosums (connects the right and left hemispheres of the brain) • - Hypothalamus • o Protic Area: greater volume in men • This area involves mating behavior and only starts to show a clear difference around the age of four. • - Limbic System • o Women are shown to have larger limbic systems, which means they tend to be more in touch with their emotions. This can be both negative and positive. • Nurturing, but more susceptible to depression

3. Female vs. Male Brain abilities • - Memory- Female • o Studies show that women have a greater ability to remember events and specifics of those events than men do. • - Spatiality Male • o Males tend to have an advantage in the ability to generate and mentally manipulate spatial representations of geometric and other figures. • - Language Abilities Female • - Auditory Evoked Response (brain wave patterns that are developed from a performance of various auditory tasks)  Females • o Females exhibit greater AER’s than males under standard conditions. • o Female brains undergo more rapid development than male brains. • - ApoptosisNerve Cell Death/Neuronal Loss With Age • o More prevalent in females in several regions of the brain

4. Female Vs. Male in Behavioral Traits • - Males exceed Females in • o Aggressiveness • Linked to testosterone • Recall Homicide examples in G&M • o Assertiveness • Males are considerably more assertive than women with forcefulness and persistence in their attempts to obtain things that they desire or to persuade others of a particular point of view. • o Ambitiousness • - Females exceed Men in • o Curiosity • o Inquisitiveness • o Extroversion • o Delayed Gratification • - Inconsistent conclusions have been drawn about • o Dogmatism (opinionated differences) • o Introversion (shyness)

5. Video • http://www.youtube.com/watch?v=NoCPDvQBG5Y

6. Perceptual Factors Perceptual factors deal with hearing, seeing, tasting, smelling, and feeling. (Cognitive senses) Auditory Perceptions has to do with the ability to hear. According to Auditory Acuity there seems to be no difference in hearing during infancy in the sexes, but from childhood onward, auditory acuity is generally greater for females than for males. *Auditory Acuity is the sharpness/ acuteness in hearing. Pitch Discrimination Between 20 to20,000 Hertz is the normal range for majority of Human adults to be able to detect pitch. Test show that there may not be a difference in young adults, but fully developed female adults have a better ability at pitch discrimination. Pure Tone Detection is the detection of single frequency tone of sound without harmonic content, which harmonic refers to a sound of which the frequency is the multiple of a number of fundamental frequencies. Women were found to detect pure tone better than men. Perceptual Factors are mainly affected by age and the development of the male and female.

7. Thermal Sensitivity • Temperature sensations that mainly occur with the skin. • Studies alter temperatures near skin and require subjects to report what differences in sensations they feel or perceive as. • Sex doesn’t affect the sensations of thermal touch or changes, both men and women are equally sensitive to temperature change. Taste and Olfactory Perceptions -Is the study of the perceptions of taste and smell. Taste Acuity/Sensitivity - Relative to eating, deals with the sharpness of taste to a human. According to Human evolution there are five different basic qualities of taste. Bitter, sour, sweet, salty, and unami. In each category women have been proven to be more sensitive to what they eat and taste, except in the salty category where they are equal to men. Olfactory Acuity/Sensitivity • Smell is an extremely precise sense in most species. Especially, for the female gender of humans, smell seems to affect their keen sensitivity to odors more than men. A test that indicated sex difference had no significance in the detection of a musky substance called exaltolide, it was then determined that age had a lot to do with the to be aware of certain odors. It was found that after puberty, females were more likely to detect exaltolide than men were. Limbic System- emotions ↓ Discrimination Between Mothers and Strangers -Studies prove that female infants are better than male infants at determining their mothers face over a strangers. Estimating/Perceiving Environmental Hazards and Risks -When compared, females had a significantly higher awareness of hazards and environmental risks than that of males. Females demonstrated higher levels of caution. -Masculinity?

8. Motor Skill Factors Studies show that males are generally more skilled with basic reflexes and coordination. Basic Reflexes and Repetitive Motor Movements -Body Twitching and Jerking in infants has been proven that boys twitch and jerk more than girls do. Eye Blink (Eyelid) Startle Response -When a matured individual is startled or disrupted suddenly their eyelids tend to twitch shut. This is a involuntary action. Through research it shows that the eye blink startle response is more pronounced in females than in males. However, when a boy is young they tend to be the gender that startles more often. Motor Coordination Factors -This skill has to do with the ability for someone to execute a muscular movement in ways that accomplish one’s intended task. -Studies have showed men to be the stronger, more coordinated gender, however age takes it toll and as he grows older he loses his motor skills quicker than a female would. -Women have been proven to be more flexible than men…especially in the mouth -On average, it’s proven that women spoke more words per minute than men do.

9. 3 Arguments and 3 Points • 3 Interesting Points • 1. Event Related Potential • i. It is interesting how women can recall specifics of events better than men. There overall memory is stronger generally, but it is especially interesting to know that there is science to support the idea that women are more about details and men are more about general aspects. • 2. Studies have shown that females are more susceptible to pain and contracting diseases. They are also more likely to seek help for that injury or sickness. This is also true in emotional sickness because women have a larger limbic system; they are more susceptible to depression and emotional distress. • 3. Associating Odor with Mood. We found it really interesting that it is more likely for a female to associate her odor with her mood than a male. Ex: According to this study, if a female is in a bad mood, she is likely to not be as presentable (smelling, cleanliness, overall appearance) as she would be if she were in a good mood.

10. 3 Arguments • 1. Attention seeking.Studies show that Males are more attention seeking. A general concensus of female interaction with males, female interaction with other females, and extensive appearance concern would argue against this.We have compared a group of women talking with a group of men talking: women talk over each other, competing for each others attention whereas men talk less, and usually one at a time. • 2. Assertion, Aggressiveness, and Ambition • i. Are these obvious to you? • ii. These conclusions seem to represent our society pretty well.As we read through this we considered if the fact that men are generally more assertive, aggressive, and ambitious, is the reason for women being seen as lower than men for so long, and for some inequalities that are still happening. • 3. A lot of studies that were given in this book seemed logically inaccurate.One study showed that males are more accurate than females in reporting heart rates and stomach contractions.It doesn’t seem plausible to measure things like this on a small scale.

11. Test Questions • T/F • 1. Age has nothing to do with the abilities of male or females in their Motor, Emotional, or Perceptual Factors (F) • 2. Males generally experiece more Motor oriented factors than females (T) • 3. In general, females are more extroverted than males. Multiple choice • Which is not a trait that women seem to carry more than men? a) curiosity b) extrovertedess c) assertiveness d) Delayed gratification • What is larger in the male brain than female? a) Corpus Collasum b) Limbic system c) Protic Area • According to studies women are more perceptual than men at… a) Taste b) Sound (on many levels) c) Feel d) Both a & b e) All of the above