William L Matzner

Bioeconomics, Behavioural Economics, Neuroeconomics

MD, PhD
24.63

Publications

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    ABSTRACT: How do human beings decide when to be selfish or selfless? In this study, we gave testosterone to 25 men to establish its impact on prosocial behaviors in a double-blind within-subjects design. We also confirmed participants' testosterone levels before and after treatment through blood draws. Using the Ultimatum Game from behavioral economics, we find that men with artificially raised T, compared to themselves on placebo, were 27% less generous towards strangers with money they controlled (95% CI placebo: (1.70, 2.72); 95% CI T: (.98, 2.30)). This effect scales with a man's level of total-, free-, and dihydro-testosterone (DHT). Men in the lowest decile of DHT were 560% more generous than men in the highest decile of DHT. We also found that men with elevated testosterone were more likely to use their own money punish those who were ungenerous toward them. Our results continue to hold after controlling for altruism. We conclude that elevated testosterone causes men to behave antisocially.
    Full-text · Article · Dec 2009 · PLoS ONE
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    Paul J Zak · Robert Kurzban · William T Matzner
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    ABSTRACT: Human beings exhibit substantial interpersonal trust-even with strangers. The neuroactive hormone oxytocin facilitates social recognition in animals, and we examine if oxytocin is related to trustworthiness between humans. This paper reports the results of an experiment to test this hypothesis, where trust and trustworthiness are measured using the sequential anonymous "trust game" with monetary payoffs. We find that oxytocin levels are higher in subjects who receive a monetary transfer that reflects an intention of trust relative to an unintentional monetary transfer of the same amount. In addition, higher oxytocin levels are associated with trustworthy behavior (the reciprocation of trust). Absent intentionality, both the oxytocin and behavioral responses are extinguished. We conclude that perceptions of intentions of trust affect levels of circulating oxytocin.
    Full-text · Article · Jan 2006 · Hormones and Behavior
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    Paul J. Zak · Karla Borja · William T. Matzner · Robert Kurzban
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    ABSTRACT: Trust is an essential component of transactions that occur over time. The amount of trust accorded to others is typically conditioned on multiple factors, including knowledge of the other party, the history of interactions, and the context of exchange. Determining who to trust and who to distrust is especially important in modern societies with largely impersonal exchange (Vernon L. Smith, 2003). In fact, trust is among the strongest predictors of whether a country will successfully develop: poor countries are by-and-large low-trust countries. This occurs because low trust inhibits investment and thereby the creation of wealth (Zak and Stephen Knack, 2001). Unfortunately, subjects in laboratory settings are unable to articulate clearly why they decide to trust or distrust a trading partner. In order to discover why human beings trust or distrust others, economists have begun obtaining physiologic measurements during trust experiments (Zak, 2005). This new transdisciplinary field is called neuroeconomics (Kevin McCabe et al.
    Full-text · Article · Feb 2005 · American Economic Review
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    Paul J Zak · Robert Kurzban · William T Matzner
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    ABSTRACT: This is the first report that endogenous oxytocin in humans is related to social behaviors, which is consistent with a large animal literature. Subjects are put into a social dilemma in which absent communication, cooperative behavior can benefit both parties randomly assigned to a dyad. The dilemma arises because one participant must make a monetary sacrifice to signal the degree of trust in the other before the other's behavioral response is known. We show that receipt of a signal of trust is associated with a higher level of peripheral oxytocin than that in subjects receiving a random monetary transfer of the same average amount. Oxytocin levels were also related to trustworthy behavior (sharing a greater proportion of the monetary gains). We conclude that oxytocin may be part of the human physiology that motivates cooperation.
    Full-text · Article · Jan 2005 · Annals of the New York Academy of Sciences
  • Geoffrey Sher · William Matzner · Penny Chong · Wendell Ching

    No preview · Article · Oct 2000 · Fertility and Sterility
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    ABSTRACT: Antiphospholipid antibodies (APA) have been identified in patients with recurrent pregnancy loss and IVF failure. Of these, antiphosphatidylethanolamine (aPE) and antiphosphatidylserine (aPS) may have special significance. A link between increased natural killer cell activity (NKa+) and trophoblast cell apoptosis has also been reported. This study was undertaken to determine how the APA profile was associated with peripheral NK cell activity. We evaluated 197 female IVF candidates for APA and NKa. Eighty-nine patients (45%) were APA+ and of these, 51 (57%) were aPE/aPS+. Fifty-four patients (27%) had increased NK cell activity. Some 51% of APA+ and 78% of aPE/aPS+ patients had increased NK cell activity compared with 8% and 13% when APA and aPE/aPS tested negative respectively (P < 0.0001). Non-male factor infertility patients were APA+ and NKa+ in 57% and 34% of cases respectively, compared with 19% and 13% if a pure male factor was present. Some 88% of aPE/aPS+, non-male factor patients had increased NK cell activity, compared with 12% who tested aPE/aPS negative (P < 0.0001) and 25% of aPE/aPS+, isolated male factor patients (P < 0.0001). These findings establish a direct relationship between APA (specifically aPE/aPS) and increased peripheral NK cell activity among non-male factor infertility patients. It is possible that APA do not directly cause reproductive failure but rather function as markers or intermediaries for an underlying, abnormal activation of cellular immunity.
    Full-text · Article · Sep 2000 · Human Reproduction
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    Penny Chong · William Matzner · Wendell Ching
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    ABSTRACT: Antiphospholipid antibodies (APAs) are important in the etiology of reproductive failure. Studies have shown that binding proteins are necessary for the detection of APAs. One of these, beta 2-glycoprotein, has been shown to be necessary for detection of anticardiolipin antibodies. It is felt that some APAs may be directed to the binding protein itself, or to a combination of the binding protein and phospholipid. In this study, a comparison of APAs vs. anti beta 2-glycoprotein antibodies was performed on the sera of 123 women younger than 40 years of age with a history of reproductive failure. Antibodies to six phospholipid epitopes, cardiolipin, phosphatidyle-thanolamine, phosphatidylserine, phosphatidylinositol, phosphatidic acid, phosphatidylglycerol, and phosphatidylserine, were measured. Of the 123 women tested, 33 had one or more positive immunoglobulin (Ig)G antibodies to phospholipids, of which 9 were to cardiolipin. However, only 1 of 123 women had IgG antibodies to beta 2-glycoprotein and she was APA negative. Thirty-eight of 123 women had one or more IgM antibodies to phospholipids, with none directed to cardiolipin IgM. In contrast, only 8 of the 123 women had IgM antibodies to beta 2-glycoprotein. Five of the eight patients had IgM APA; 4 of 5 had IgM antibodies to PE, 1 to PI. There is no correlation between beta 2-glycoprotein antibodies and APA status in this population. To date, our most sensitive test for detecting phospholipid autoimmune-mediated in vitro fertilization failure still appears to be the ELISA assay for APA.
    Full-text · Article · Jan 1999 · American journal of reproductive immunology (New York, N.Y.: 1989)
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    ABSTRACT: RESULTS: In phase I, 687 women who tested APA+ to one or more PL epitopes underwent two or fewer IVF attempts for a total of 1050 IVF cycles. Four hundred seventy-seven (46%) births occurred in 923 IVF cycles in which H/A alone was administered. Twenty-two (17%) births occurred after 127 IVF cycles in which H/A was not administered. In phase II, 322 of 687 women tested positive for a single APA subtype. These subjects underwent up to two consecutive IVF attempts for a total of 521 IVF cycles while receiving H/A alone. The birthrate was significantly lower for women whose APAs were directed toward phosphatidylethanolamine (PE) or phosphatidylserine (PS) involving IgG or IgM isotypes than for women who had any other APA (17% vs. 43%). In phase III, 121 women who did not achieve live births after two consecutive IVF attempts in which H/A alone was administered received IVIg in combination with H/A during their third consecutive IVF cycle. The birth rate was 41% after these IVF cycles when anti-PS or anti-PE involving IgG or IgM isotypes were present, as compared with 17% when H/A alone was administered. The IVF outcome did not improve when IVIg was administered in association with any other single APA.
    Full-text · Article · Sep 1998 · American journal of reproductive immunology (New York, N.Y.: 1989)
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    ABSTRACT: 1) Does the administration of heparin and aspirin (H/A) in combination with intravenous immunoglobulin G (IVIG) improve in vitro fertilization (IVF) implantation and birth rates in patients with recurrent IVF failure? 2) Is the effect of such treatment related to the antiphospholipid antibody (APA) status of the patients concerned? Subjects consisted of 89 women younger than 36 years of age whose infertility was a result of causes other than male infertility and who had experienced four or more failed IVF/embryo transfer procedures. Fifty-two women were APA+ (group A), and 37 were APA- (group B). All patients, regardless of their APA status, received H/A (5000 U sq bid), aspirin (81 mg po qd) from the inception of menotropin therapy along with IVIG (20 g) through a single infusion 3 to 10 days before egg retrieval. Twenty-two (42%) of group A and 7 (19%) of group B patients achieved live births (P = 0.020). IVF outcome is significantly improved when H/A and IVIG are administered to APA+ women with repeat IVF failures. APA- women do not seem to benefit from such treatment.
    Full-text · Article · Jul 1998 · American journal of reproductive immunology (New York, N.Y.: 1989)
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    ABSTRACT: To compare the effect of heparin/aspirin therapy alone vs. heparin/aspirin in combination with intravenous immuno-globulin (IVIg) immunotherapy on in vitro fertilization (IVF) outcome of patients who test positive for antithyroid antibodies (ATAs). Eighty-two women younger than 40 years of age whose infertility was related exclusively to female causes were evaluated. All tested positive for organ-specific antithyroid antibodies (antimicrosomal and/or antithyroglobulin antibodies), but negative for antiphospholipid antibodies. Thirty-seven of these women (group A) received H/A alone, whereas 45 (group B) received heparin/aspirin in combination with IVIg. Ten (27%) of women in group A and 23 (51%) of women in group B achieved live births after completion of a single IVF/embryo transfer cycle (P = 0.027). We conclude that IVIg therapy significantly improves IVF success rates in ATA+ women.
    No preview · Article · Apr 1998 · American journal of reproductive immunology (New York, N.Y.: 1989)
  • W Matzner · P Chong · W Ching

    No preview · Article · Feb 1998 · Fertility and Sterility

  • No preview · Article · Jan 1998
  • Geoffrey Sher · William Matzner · Penny Chong · Wendel Ching

    No preview · Article · Nov 1995
  • G Sher · M Feinman · C Zouves · G Maasarani · R Salem · W Matzner · W Ching · P Chong

    No preview · Article · Jun 1995 · Human Reproduction
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    W Matzner · P Chong · G Xu · W Ching
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    ABSTRACT: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (< 10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (> 50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment.
    Full-text · Article · Feb 1995 · American journal of reproductive immunology (New York, N.Y.: 1989)
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    Penny J. Chong · William L. Matzner · Wendell T. W. Ching
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    ABSTRACT: Traditionally, four main causes are considered in evaluating patients with a history of recurrent spontaneous abortion: infection, chromosome abnormalities, low progesterone levels, and anatomic abnormalities. However, the majority of such losses are mediated by immune dysfunction, including inadequate maternal antipaternal leukocyte antibodies and the presence of antiphospholipid antibodies and antinuclear antibodies. Immunologic problems are easily identified and treated using modalities such as paternal leukocyte immunization, prophylactic heparin, baby aspirin, and low-dose prednisone. With appropriate and timely treatment, the success rate is approximately 80%.
    Full-text · Article · Jan 1995
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    ABSTRACT: This study was undertaken to explore whether intervention with heparin and aspirin (H/A) in selected patients undergoing in-vitro fertilization (IVF) and embryo transfer could improve fecundity rates. Specifically, it explored the possibility that women diagnosed with organic pelvic disease who demonstrated antiphospholipid antibodies (APA) could benefit from H/A administration in a similar manner to that used in patients with recurrent pregnancy loss. We used an enzyme-linked immunosorbent assay for six different phospholipids to identify patients who expressed APA before they underwent IVF/embryo transfer. This study was confined to the first IVF/embryo transfer cycle that followed assessment of APA status and accordingly, the number of IVF/embryo transfer cycles corresponds with the number of patients treated. APA seropositive patients were treated with aspirin, 81 mg orally q.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 of controlled ovarian stimulation. The endpoint for success was a live birth or an ultrasound confirming fetal cardiac activity (a viable pregnancy). The prevalence of APA in patients diagnosed with organic pelvic disease (53%) was much higher than in those without female pathology (14%). The administration of H/A to APA seropositive patients significantly (P < 0.05) improved the viable pregnancy rate (49%) compared to the untreated APA seropositive group (16%). The viable pregnancy rate for APA seropositive women treated with H/A was also significantly (P < 0.001) higher than for untreated APA seronegative patients (27%). We conclude that all women undergoing IVF/embryo transfer should be tested for APA prior to initiating ovarian stimulation and those with APA seropositivity should be treated with H/A.
    Full-text · Article · Jan 1995 · Human Reproduction
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    W Matzner · P Chong · G Xu · W Ching
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    ABSTRACT: Antiphospholipid antibodies are important in the etiology of recurrent pregnancy loss. To date, most studies have concentrated on antibodies to cardiolipin specifically. In this study, the serum of 352 women with recurrent pregnancy loss was studied by enzyme-linked immunosorbent assay for antibodies to six phospholipid epitopes: cardiolipin, phosphoserine, phosphoglycerol, phosphoethanolamine, phosphatidic acid and phosphoinositol. Of these women, 59.1% had either an IgG or IgM antibody to one of the six phospholipids. This compared to only 4.6% in the control group. Approximately 75% of the isotypes were IgM. The most common phospholipid epitope was phosphoserine. However, in patients with antibodies to only one phospholipid, phosphoethanolamine was the most common. These findings support recent evidence that antiphospholipid antibodies may interfere with the formation of syncytiotrophoblasts in the placenta. In addition, antiphospholipid antibodies occur more frequently in patients who suffer recurrent miscarriages than was previously thought.
    Full-text · Article · Feb 1994 · The Journal of reproductive medicine
  • P J Chong · W L Matzner · W.T.W. Ching

    No preview · Article · Jun 1993 · Fertility and Sterility
  • P J Chong · W L Matzner · W T Ching

    No preview · Article · Feb 1993 · Fertility and Sterility

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