Peer-Reviewed Studies on Sexuality Since 1990
(in reverse chronological order)
 |
DATE / PLACE
PUBLISHED |
DESCRIPTION |
Pro, Neutral, or
Con |
| 1. |
2006: June 28
Proceedings of the National Academy of Sciences
|
Anthony Bogaert, Ph.D., published an article on June 28, 2006, in Proceedings of the National Academy of Sciences:
"Only biological older brothers (reared with or not) and no other sibling characteristic, including nonbiological older brothers and the time reared with older biological or older nonbiological brothers, predicted men's sexual orientation. ...
These results
support a prenatal origin to sexual orientation development in
men...
A mother's body may have a memory for male (but not female) fetuses because she herself is female, and thus, her immune system may interpret and remember male ... fetuses as foreign. ...
...[T]he link between the mother's immune reaction
and the child's future sexual orientation would probably be some effect
of maternal anti-male antibodies on the sexual differentiation of the
brain."
06/28/06 Anthony Bogaert 
|
Pro |
| 2. |
2006: May 8
Proceedings of the National Academy of Sciences
(Vol. 84, No. 1, pp. 35-42) |
Ivanka Savic-Berglund, M.D., Ph.D. in an interview with New Scientist about her research team's May 8, 2006 paper "Brain Response To Putative Pheromones in Lesbian Women" published in the journal Proceedings of the National Academy of Sciences, stated:
"Our study can't answer questions of cause and effect. We can't say whether the differences are because of pre-existing differences in their brains, or if past sexual experiences have conditioned their brains to respond differently."
5/8/2006 Ivanka Savic-Berglund
New Scientist published an article on May 8, 2006 about Dr. Savic's findings:
"Lesbian and heterosexual women respond differently to specific human odours, a brain-scanning study has found. The homosexual women showed similar brain activity to heterosexual men when they inhaled certain chemicals, which may be pheromones, the researchers say.
When the heterosexual women smelled AND [a chemical produced by males] their brains showed activity in the anterior hypothalamus, a region of the brain thought to process sexual cues. But EST [a chemical produced by females] only produced activity in the olfactory region of their brains, the area that processes smells. The lesbians, however, only showed activity in the olfactory region whichever odour they smelled."
5/8/2006 New Scientist
|
Neutral |
| 3. |
2005: June 3
Cell
(Vol. 121, pp. 785-794) |
Researchers Ebu Demir and Barry J.
Dickson, Ph.D. of the Institute of Molecular Biotechnology of the Austrian
Academy of Sciences, in their 6/3/05 article in the journal Cell, "Fruitless Splicing Specifies Male Courtship Behavior in Drosophila," (Vol. 121, pp. 785-794) (see full article in PDF) stated:
"We show that male [gene] splicing is essential for male courtship
behavior and sexual orientation. More importantly, male [gene]
splicing is also sufficient to generate male behavior in otherwise normal
females. These females direct their courtship toward other females
(or males engineered to produce female pheromones).
The splicing of a single neuronal gene thus specifies essentially all aspects of a complex innate behavior."
6/3/05 Ebru Demir , Barry Dickson
|
Pro |
| 4. |
2005: May
Proceedings of the
National Academy of Sciences
(Vol. 102, No. 19) |
Ivanka Savic-Berglund, M.D., Ph.D. et al., in their May 2005 article in the journal Proceedings of the National Academy of Sciences "Brain Response To Putative Pheromones In Homosexual Men," (Vol. 102, No. 19) stated:
"These findings show that our brain
reacts differently to the two putative pheromones compared with common
odors, and suggest a link between sexual orientation and hypothalamic
neuronal processes."
5/05 Ivanka Savic-Berglund
A 5/10/05 article in the New York
Times, "For Gay Men, an Attraction to a
Different Kind of Scent," by Nicholas Wade, stated:
"Using a brain imaging technique, Swedish researchers have shown that
homosexual and heterosexual men respond differently to two odors that
may be involved in sexual arousal, and that the gay men respond in the
same way as women. The new research may open the way to studying human
pheromones, as well as the biological basis of sexual preference.
Pheromones, chemicals emitted by one individual to evoke some behavior
in another of the same species, are known to govern sexual activity in
animals, but experts differ as to what role, if any, they play in making
humans sexually attractive to one another."
5/10/05
New York Times
|
Neutral |
| 5. |
2003:
October
Behavioral Neuroscience
(Vol. 117, No. 5,
pp. 1096-1102) |
Qazi Rahman, Ph.D. et. al., in their October 2003
article in the journal Behavioral Neuroscience (Vol. 117, No. 5, pp. 1096-1102) stated:
"The present study examined the eyeblink startle
responses to acoustic stimuli of 59 healthy heterosexual and homosexual
men and women. Homosexual women showed significantly masculinized PPI
compared with heterosexual women, whereas no difference was observed in
PPI between homosexual and heterosexual men. These data provide the
first evidence for within-gender differences in basic sensorimotor
gating mechanisms and implicate the known neural substrates of PPI in
human sexual orientation."
10/03 Qazi Rahman
Lead researcher Qazi Rahman, Ph.D. said in a 2003 press
release:
"Because the startle response is known to be involuntary rather than learned,
this strongly indicates that sexual orientation is largely determined
before birth."
10/03 Qazi Rahman, Ph.D.
|
Pro |
| 6. |
2003:
October
Archives of Sexual Behavior
(Vol. 32, No. 5, pp.
403-417)
|
Robert L. Spitzer, M.D.
et. al., in
their October 2003 article in the journal Archives of Sexual
Behavior (Vol. 32, No. 5, pp. 403-417) stated:
"This
study tested the hypothesis that some individuals whose sexual
orientation is predominantly homosexual can, with some form of
reparative therapy, become predominantly heterosexual...
The majority of participants
gave reports of change from a predominantly or exclusively homosexual
orientation before therapy to a predominantly or exclusively
heterosexual orientation in the past year. Reports of complete change
were uncommon. Female participants reported significantly more change
than did male participants...
Thus, there is evidence that change in sexual
orientation following some form of reparative therapy does occur in some
gay men and lesbians."
10/03 Robert Spitzer
|
Con |
| 7. |
2003: June 30
Presented at the annual conference of the European Society of
Human Reproduction and Embryology, Madrid, Spain
|
Rina Agrawal, M.D., Ph.D., et al., in their
June 30, 2003 presentation at the
annual conference of the European Society of Human Reproduction and
Embryology, stated:
"Preliminary research suggests that 'Lesbians are more than twice
as likely to suffer from a hormone-related condition [polycystic ovary
syndrome], fueling theories that hormones play a role in developing
their sexuality.'
...while there was no evidence that polycystic
ovaries could be implicated as a cause of lesbianism, it was possible
that this hormone imbalance could be linked to both the medical
condition and sexuality."
6/30/03 Rina Agrawal
|
Pro |
| 8. |
2002:
Sept.
16
Proceedings of the National Academy of Sciences
Vol. 99, No. 20,
pp. 13232-13237 |
Toshihiro Kitamoto, Ph.D., et al., in their
Sept. 16, 2002 article in Proceedings of the National Academy of
Sciences, stated:
"Scientists say they have found a way to 'switch'
homosexual behavior on and off in male fruit flies.
The researchers were able to do
this by temporarily disrupting synaptic transmissions in the flies.
Previous research indicated that the sexual
orientation of fruit flies is genetically determined, but the brain
pathways for controlling sexual preference weren't clear."
9/16/02
Toshihiro Kitamoto
|
Pro |
| 9. |
2000:
June
16
Psychological Reports
Vol. 86, No. 3, Pt. 2, pp. 1071-1088 |
Joseph Nicolosi, Ph.D., et al., in a 2000 Psychological Reports study, stated:
"We present the results of a survey of 882 dissatisfied homosexual people whom we queried about their beliefs regarding conversion therapy and the possibility of change in sexual orientation...
Of the 882 participants, 726 of them reported that they had received conversion therapy from a professional therapist or a pastoral counselor...
Before treatment or change, only 2.2% of the participants perceived themselves as exclusively or almost entirely heterosexual, whereas after treatment or change, 34.3% perceived themselves as exclusively or almost entirely heterosexual...
As a group, the participants reported large and statistically significant reductions in the frequency of their homosexual thoughts and fantasies that they attributed to conversion therapy or self-help. They also reported large improvements in their psychological, interpersonal, and spiritual well-being."
2000 Joseph Nicolosi
|
Con |
| 10. |
1999:
June
Archives of Sexual Behavior
Vol. 28, No. 3, pp. 213-221 |
Anthony Bogaert, Ph.D., in a 1999 Archives of Sexual Behavior article, "The Relation Between Sexual Orienation and Penile Size," stated:
"The relation between sexual orientation and penile dimensions in a large sample of men was studied...
Penile dimensions were assessed using five measures of penile length and circumference from Kinsey's original protocol. On all five measures, homosexual men reported larger penises than did heterosexual men.
Alterations of typical levels of prenatal hormones in homosexual men may account for these findings."
1999 Anthony Bogaert
|
Pro |
| 11. |
1998:
March
Proceedings of the National Academy of
Sciences
Vol. 95, No. 5,
pp. 2709-2713 |
Dennis McFadden, Ph.D. et al., in
their March 1998 article in Proceedings of the National Academy of
Sciences, stated:
"Researchers say they have found the first strong evidence of a physical difference between lesbians and straight women -- a finding
that the inner ears of gay women work more like those of men.
The discovery adds new support to the theory that
sexual orientation may be predisposed at birth."
3/98 Dennis McFadden
|
Pro |
| 12. |
1993:
July
Science
Vol. 261, No. 5119, pp. 291-292 |
Dean H. Hamer, Ph.D., et. al, in their July 1993 article in Science (Vol. 261, No. 5119, pp. 291-292) stated:
"DNA
linkage analysis of a selected group of 40 families in which there were
two gay brothers and no indication of nonmaternal transmission revealed
a correlation between homosexual orientation and the inheritance of
polymorphic markers on the X chromosome in approximately 64 percent of
the sib-pairs tested.
The linkage to markers on Xq28, the subtelomeric
region of the long arm of the sex chromosome, had a multipoint lod score
of 4.0 (P = 10(-5), indicating a statistical confidence level of more
than 99 percent that at least one subtype of male sexual orientation is
genetically influenced."
7/93 Dean Hamer
|
Pro |
| 13. |
1991: December
Archives of General Psychiatry
Vol. 48, No. 12,
pp. 1089-1096 |
J. Michael Bailey, Ph.D., and Richard C.
Pillard et al., in their December 1991 article in Archives of General
Psychiatry (Vol. 48, No. 12, pp. 1089-1096) stated:
"Of the relatives whose sexual orientation could be
rated, 52% of monozygotic cotwins, 22% of dizygotic cotwins, and 11% of
adoptive brothers were homosexual. Heritabilities were substantial under
a wide range of assumptions about the population base rate of
homosexuality and ascertainment bias."
12/91 J. Michael Bailey, Ph.D. , Richard Pillard, M.D.
|
Pro |
| 14. |
1991:
June
Science,
Vol. 253,
pp. 1034-1037 |
Simon LeVay, Ph.D., et al., in their June 1991 article "A
Difference in Hypothalamic Structure Between Heterosexual and Homosexual
Men" in Science (Vol. 253, pp. 1034-1037) stated:
"The
discovery that the nucleus differs in size between heterosexual and
homosexual men illustrates that sexual orientation in humans is amenable
to study at the biological level, and this discovery opens the door to
studies of neurotransmitters or receptors that might be involved in
regulating this aspect of personality. Further interpretation of the
results of this study must be considered speculative."
6/91 Simon LeVay
Related Links: "Are there physical differences in the brain structure of heterosexual and homosexual people?" |
Pro |