In search if an etiological model of pedophilia
Kurt Freund*
Abstract
Epidemiological and "quasi-developmental" research into pedophilia is
reviewed. Both types of inquiry were made possible only by the use of the
phallometric method which assesses erotic sex and age preferences by continuous
recording of penile volume changes. This method by itself, however, has
shortcomings, which are pointed out. It appears likely that pedophilia research
may acquire a firmer basis by further development of brain imaging.
Key words
Pedophilia; Phallometry; Brain Imaging.
Definition
Pedophilia belongs among the paraphilias, or pathological erotic preferences.
These can be crudely divided into two broader categories: paraphilic "target"
preferences and paraphilic activity preferences. In the former, the targets of
erotic or sexual cognition are not primarily (other) physically mature persons,
and the paraphilic activity preferences are characteristically highly atypical
for sexually normal persons. Pedophilia seems to be primarily a target
preference, however, it has been more recently demonstrated that there are
regular connections between paraphilic activity preferences and target
preferences (Freund, 1994).
Identification of the Disorder
The recognition of pedophilia as a specific disorder is attributable to
Krafft-Ebing (1886); however, some authors continue to use this term to denote a
variety of different clinical pictures. This was pointed out by Ames and Houston
(1990) and Araji and Finkelhor (1985). The revised third edition of the
Diagnostic and Statistical Manual of Mental Disorders (D.S.M. III-R, 1987) lists
the essential feature of pedophilia as "recurrent, intense sexual urges and
sexually arousing fantasies of at least six months’ duration, involving sexual
activity with a pre-pubescent child" (p. 284). For our purposes the period of
childhood is defined as ending at age 12, an age limit adopted from Gebhard et
al. (1965).
Diagnosis and Diagnostic Research
Fantasies focusing on children, as mentioned in D.S.M. III-R (1987), do
constitute one of the foremost characteristics of pedophilia, however, relying
on self-reports of fantasies is of little diagnostic value since pedophiles
rarely admit their true erotic fantasies. Because pedophilia is very rare in
females (Gebhard et al., 1965), all diagnostic research could be focused on
males only. Therefore, instead of relying on reports of such fantasies, we have
been diagnosing pedophilia by phallometry, which is a continuous recording of
penile volume changes during the presentation of pictures of nude female and
male children and adults. According to their phallometric responses, pedophiles
are those who erotically prefer children to adults. This is also the case when
the stimuli are verbal and depict sexual interaction between the tested
individual and a child versus such sexual interaction with an adult.
Phallometrically, about 80% of sex offenders who victimized two or more children
(unrelated to them) are diagnosed as pedophiles, whereas only about 5% of sex
offenders against women are mis-diagnosed as pedophiles (Freund and Watson,
1991). It must pointed out, however, this data was collected from labs using
volumetric phallometry, a computer diagnosis which included signals of faking,
and strong stimuli; hence our results may be more reliable than those of less
equipped labs.
Therapy and Therapy-Research
There are currently three therapeutic approaches. The first is psychotherapy,
derived from experiments with animals (Pavlovian and Skinnerian learning — Laws
and Marshall, 1990; Pithers, 1990). The second focuses on serotonergic
medication (see the critical review by Federoff, 1993). Lastly, the third is sex
drive reducing medication or sex drive reduction by testicular enucleation
(Berlin and Meinecke, 1981; Freund, 1980; Hucker, 1985, 1992; Wille and Beier,
1989).
The opportunistic offenders will probably profit from any kind of
psychotherapy or counseling and from punishment itself also. However, although
the phallometric method is fraught with insufficiencies, it still reliably
divides therapeutic candidates into true pedophiles and opportunistic sex
offenders against children. Once this division has been made, the assessment of
therapeutic effect could be carried out separately for each of these two
offender groups. For many reasons, the long-term use of the various medications
is not feasible and testicular enucleation as a therapy for the paraphilias is
socially unacceptable in most western countries.
Epidemiological Research
The following was an epidemiological study which also has etiological
implications. Epidemiological studies can currently be conducted only with
individuals accused of offenses against children, and not with pedophiles
proper. Only in rare cases are such sex offenders against children individually
assessed and differentiated into true pedophiles and opportunistic offenders. At
present, similar serious limitations hamper all systematic research on
pedophilia.
Two earlier studies on paraphilias (Gebhard et al., 1965; Mohr et al., 1964)
reported that the proportion of sex offenders against female children to that of
sex offenders against male children was about 2:1. In our own endeavors (Freund
et al., 1984; 1987)) we also found a similar proportion. A literature search
(Cameron, 1985) that involved 17 additional studies on sex offenders against
children, listed the ratio of victimized female to male children in the majority
of cases also as approximately 2:1. This differs substantially from the ratio of
gynephiles (men who erotically prefer physically mature females) vs. androphiles
(who erotically prefer adult members of their own sex) which is minimally 20:1 (Gebhard,
1972; Hirschfeld, 1920; Kinsey et al., 1948; Whitam, 1983).
The discrepancy between the proportions of heterosexual and homosexual
offenders against children, on the one hand, and of gynephiles and androphiles
on the other, was unexpectedly large. However, Abel et al. (1987; 1988) reported
that sexual offenders against male children have many more victims than such
offenders against female children. According to the data of these authors,
the mean number of victims of offenders against female children was 19.8, while
that of such offenders against male children was 150.2. Abel et al. (1987,1988)
pointed out that the much larger number of victims of offenders against male
children increases the risk of these offenders’ being caught. However, the rate
of increase for this risk and the number of victims remains unknown. Mohr et al.
(1964) also reported a higher recidivism rate in sex offenders against male
children, as contrasted with sex offenders against female children. Fitch (1962)
concurred; whereas Gebhard et al. (1965) reported only a marginal difference.
The tendency of the offenders against male children to have a greater number
of victims suggests that this group may contain a larger proportion of true
pedophiles than the group of offenders against female children. This conjecture
concurs with the results of two earlier studies. One of these studies, (Freund
et al., 1987), compared sex offenders against female minors and sex offenders
against male minors ("incest" offenders excluded). Among the offenders against
female children there were more individuals who had only one victim rather than
two or more victims, whereas among offenders against male children the opposite
was true.
Another earlier study calculated the sensitivity of the phallometric method
in diagnosing multi-victim offenders against girls, and used the ratio of those
diagnosed versus non-diagnosed as pedophiles with single-victim offenders, to
arrive at an estimate of the numbers of true pedophiles in this group. A similar
operation was carried out using other specified subgroups and analogously with
offenders against male children (Freund and Watson, 1991).
Using these estimates, we converted the "raw" proportions of specified
subgroups within the group of sex offenders against female children and within
the group of sex offenders against male children into estimates of the
proportions of "true" heterosexual and homosexual pedophiles. The result of this
conversion was a ratio of heterosexual versus homosexual pedophiles of 1.44:1.
However, the earlier cited finding of Abel et al. (1988) of a mean number of
victims 7.6 times larger for offenders against male children than the mean
number of victims for offenders against female children also has to be
considered. After recalculation of this increased risk of an offender’s being
caught, and under the supposition that this risk increases proportionally and
linearly with each victim, our estimate of the ratio of the offenders against
female children versus offenders against male children was recalculated to
approximately 11:1. For a number of reasons, this may be an upper limit or, more
likely, quite exaggerated. One reason is that this estimate did not take into
account that the low number of victims of offenders against female children,
found by Abel and co-workers, must have been strongly influenced by the fact
that there were substantially fewer pedophiles among the offenders against
female children than there were against male children. The ratio of heterosexual
to homosexual pedophiles was, however, still substantially smaller than the
ratio of heterosexual versus homosexual males who erotically preferred
physically mature persons. The most parsimonious interpretation of this result
is that the heterosexual and homosexual types of pedophilia are substantially
more closely related to each other than to the heterosexuality or homosexuality
of males who erotically prefer physically mature partners. Also, pedophilia has
little in common with homosexuality or heterosexuality in males who prefer
physically mature partners.
Differences in Self-Reported Masculinity and Femininity
The derived proportion of heterosexual and homosexual pedophiles given above,
appears to indicate that there may be differences other than sex-preference
between them.
Two earlier studies (Freund and Blanchard, 1987; Freund et al., 1984)
demonstrated that Part A of the Gender Identity scale (Freund et al., 1974;
1977) successfully differentiated between androphiles and offenders against male
children, but not between offenders against male children and offenders against
female children. On the other hand, the 1987 study (quoted above) seems to
indicate that Blanchard’s (1983) retrospective Physical Aggressiveness scale
differentiated between homosexual and heterosexual pedophiles. However, this
study was a comparison of sex offenders against female children and sex
offenders against male children, and not of phallometrically diagnosed
heterosexual and homosexual pedophiles. It may have been confounded by the
differing proportions of true pedophiles among the heterosexual and homosexual
offenders. This comparison has to be replicated with phallometrically diagnosed
pedophiles before it can be acknowledged as valid.
The Abused Abuser Theory
One of our two solely etiological studies was about the abused abuser theory
of pedophilia. The majority of professionals (and particularly of
semi-professionals) working in the area of pedophilia believes that this
propensity is due primarily, if not exclusively, to an individual’s
developmental experience rather than to a pre-experiential innate or
physiologically acquired condition. The prevailing version of this conjecture
supposes that pedophilia, or at least an individual’s proneness to sexually
offend in adulthood, is due to having been sexually abused in childhood by an
adult. The main problem with this conjecture is its dependence on
self-reports about childhood sexual abuse among accused or charged sex offenders
against children. It has been shown that a large proportion of such offenders
fabricate childhood sexual abuse as an excuse or form of exoneration for their
behavior (Hindman, 1988).
Two of our earlier publications on this topic (Freund et al., 1990; Freund
and Kuban, 1994), using various groups of males, investigated the connection
between the subject’s retrospective self-reports of having been sexually abused
in childhood, his erotically preferred age bracket, and type of offense. The
earlier of these two studies was only preliminary and will not be discussed in
detail. The second study included 83 pedophilic sex offenders against female
children, 52 sex offenders against female children who, however, erotically
preferred adult women, 34 sex offenders against adult women and 134 gynephilic
volunteer controls. The differentiation between pedophilic and non-pedophilic
sex offenders against children was determined by means of phallometry.
The main statistical procedure used in this study was logistic regression.
The result verified two significant predictors: erotic age preference
(pedophilia versus an erotic preference for adults), and sex offender status.
However, this latter predictor, was actually a combination of two predictors,
namely, status of a sex offender against children and status of a sex offender
against adult females. It derived its predictive potential mainly from the
status of being a sex offender against children. The described result seemed to
support the abused abuser theory. We must, however, not forget that this study
could only test the validity of the clinical observation of a higher frequency
of self-reports of (heterosexual) pedophiles having been sexually abused in
childhood and not whether the pedophiles were really sexually abused.
Finkelhor (1984) pointed out the presence of a large "error" of the abused
abuser theory. The present study specified this error: Only about one third
of the pedophiles indicated sexual abuse in their childhood. Under these
conditions it would be a mistake to conclude that an association between
pedophilia and a self-report indicating sexual abuse in childhood, settles the
problem of causation of pedophilia. Further etiological possibilities will
have to be investigated.
Because of the demonstrated possibility of a physiological disposition
towards pedophilia, the following discusses research into the physiological
aspects, which has been and is largely omitted, in particular by learning
theorists and "anthropological" ethologists (Feierman, 1990). First, however, a
reminder to avoid misunderstandings. The popular division of etiologies into
"innate" and learned (experiential) is misleading and should instead be replaced
by examining the nature of the involvement of each component. However, the
difference between females and males in regard to pedophilia (mentioned earlier)
makes it very likely that there is a strong physiological factor.
Retrospective Self-reports about Erotic Curiosity
The "Abused Abuser" study indicated that a majority of pedophilic sex
offenders did not report seduction in childhood. We tried to re-investigate
this incongruity. This additional research was an attempt to specify when the
first difference appeared between male children and pubescents who as adults
would prefer children and those who would prefer physically mature persons. We
approached this problem also by means of a self-report study (Freund and Kuban,
1993).
This study investigated three aspects of the development of erotic sex and
age preferences in males: (a) whether the supposition of a strong innate factor
or an early postnatally acquired factor (most likely physiological) in the
development of pedophilia can be supported by childhood memories, (b) whether
the experience of an almost abrupt decrease in the erotic appeal of children in
boys who later become gynephilic, can be supported by the retrospective
self-reports of a large group, (c) whether the establishment of erotic sex
preference precedes the establishment of erotic age preference.
This study made two initial suppositions: (a) that curiosity to see persons
in the nude during childhood can be viewed as an indicator of developing erotic
interest, and (b) that the retrospective self-reports used in the study
reflected reality sufficiently and could be employed in probing the development
of erotic curiosity in childhood. The subjects of the study were
phallometrically diagnosed pedophiles who admitted to having sexual fantasies
about children or pubescents, and control volunteers. The inquiry consisted of
the following eight questions incorporated in the Sexual Preferences Scheme (EPES,
Freund, 1965, unpublished): 1 Prior to age 7 were you curious to see female
children your age in the nude? 2 Prior to age 7 were you curious to see female
grown ups in the nude? 3 Between ages 7 and 11 were you curious to see female
children your age in the nude? 4 Between ages 7 and 11 were you curious to see
female grown ups in the nude? The four additional EPES questions (5 to 8) had
the same wording, with the difference being that the word "female" was replaced
by "male".
The retrospective reports about childhood curiosity differed substantially
from the earlier described retrospective self-reports concerning sexual abuse in
childhood, which, when answered in the positive, could to some degree exonerate
the offender and fault the earlier abuser. None of the possible answers to the
questions asked in this study was as obviously endowed with the potential to
bias an interviewer favorably towards the offender, and if occurring, the most
likely distortion resulting from offender bias would be a diminution of the true
number of pedophiles claiming a childhood curiosity to see nude children.
The results of the study suggested that a greater proportion of pedophiles
reported a childhood curiosity to see nude children and not adults than did the
other groups. This suggests that, in a substantial proportion of pedophiles
(possibly in all of them), this paraphilia may well have been present from early
childhood or infancy or may have developed from an innate disposition. The study
also suggested that throughout the developmental process of erotic sex and age
preferences in males, the establishment of erotic sex preference precedes that
of erotic age preference, and that the establishment of erotic sex preference in
gynephiles and heterosexual pedophiles occurs earlier than it does in
androphiles and homosexual pedophiles. Furthermore, according to the memories of
volunteer gynephiles, the almost abrupt decrease of the impact of the erotically
non-preferred age bracket, in this case of female children, occurred around the
onset of puberty.
The two initial suppositions, on which this study was based, were a, that
curiosity to see persons in the nude during childhood can be viewed as an
indicator of developing erotic interest, and b, that the retrospective
self-reports used in the study, reflected reality sufficiently and could be
employed in probing the development of erotic curiosity in childhood, were
proven adequate. The adequacy of our first supposition was made plausible by the
observed increase of curiosity to see persons in the nude during the latter
years of childhood, as contrasted with the period prior to age 7. The second
supposition was made plausible by the high proportion of individuals who
reported such a curiosity in regard to persons of the sex and age they preferred
in adulthood.
A study by Gaffney et al., (1984) appears to suggest that this physiological
factor is genetic. This study compared relevant information about the prevalence
of the various kinds of paraphilias in first degree relatives of 33 pedophiles
(defined according to DSM - III) hospitalized at Johns Hopkins for therapy, and
of 33 patients hospitalized for depression. There was a greater prevalence of
paraphilics in the families of the pedophilic probands and all were
characterized by the probands as pedophiles and as males. The various
paraphilics in the control group of depressives indicated a variety of
paraphilias in their families. Furthermore, in contrast to the pedophilic
sample, the morbidity risk in regard to paraphilias (calculated by means of a
shortened Weinberg method) among the relatives of the paraphilics in the control
sample was minimal. Our clinical experience does not correspond to these
findings but our questioning of patients in this regard was quite superficial.
There may exist a genetic form of pedophilia without this disturbance being
genetically transmitted in most cases. A patient whose pedophilia may have been
due to genetic transmission was described in an earlier study (Freund and
Blanchard, 1993, p. 560/561). He had four brothers, one of them, his twin, is
most likely also pedophilic (see original study). Among the three older
brothers, two started approaching him sexually when he was 10 years old. I saw
both in adulthood when they were charged for pedophilic offenses.
Another type of findings, relevant to a possible physiological disposition
towards pedophilia was reported by Langevin and his group. These investigators
reported crude structural anomalies of the brain of pedophiles, detected by CAT
(computer assisted tomography, — Langevin et al., 1985, 1988; Hucker et al.,
1988, 1992; Wright et al., 1990). These studies are still in their initial
phase.
Options for Further Research
The reviewed pedophilia studies were epidemiological and
"quasi-developmental". Both types involved phallometry.
Quasi-developmental research uses retrospective self-reports about childhood
experiences, behavior, or ideation, and may reveal promising directions for
later true developmental research. The main shortcoming of our epidemiological
pedophilia research is the lack of reliable methods of transforming assessments
of large numbers of sex offenders against children into such outcomes regarding
pedophiles.
The transformations used in the present epidemiological study compared the
ratios of heterosexual and homosexual pedophiles. However, the number of victims
of homosexual sex offenders against children appears exceptional; the increase
of the risk of being caught, with the increasing number of victims, was
arbitrary, and intentionally set to be rather too high than too low. This kind
of research can be improved by utilizing various combinations of a number of
types of subject selections. The phallometric assessments involved in both types
of research need improvement. In particular, they should specify offender groups
which are currently lumped together (e.g. homosexual pedophiles and hebephiles).
However, even such improved research in pedophilia can not be expected to
render substantially more certain results than individual clinical observation.
It also is to be expected that a majority of such research efforts will turn out
to be irrelevant. Would it not be better to devote the manpower and funds
available for research to more promising ("less risky") endeavors. Why should
the practical urgency of the problem of pedophilia take precedence over the lack
of scientific feasibility in this area?
On the other hand, for the systematic observer, this may not be a sufficient
reason to leave her or his own clinical impressions unexplored, or to cease
testing the clinical impressions of others. This pertains only if the methods
used in such explorations are of sufficient clarity and can be formulated
unambiguously enough to make replication possible by alternative methods.
The present writer’s impression is that the kind of research most promising
in this area, and possibly the most feasible in the not too remote future would
examine anomalies in brain structure. However, the possibilities of finding
connections between pedophilia and insufficiencies in neural structures provided
by CAT (computer assisted tomography) are very limited, and PET (positron
emission tomography) can not be used for repeated assessments within a
relatively short time period. MRI (magnetic resonance imaging) does have these
problems to a much lesser degree, however, the spatial resolution achieved may
still not be sufficient. The most recent development, the MSI (magnetic source
imaging) however, which is a combination of Supermagnet MRI with EEG scanning (Gallen
et al., 1993), appears promising in resolving this difficulty and may develop
enough in the not too distant future sufficiently, to make possible the
localization of brain structures relevant to paraphilia research.
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