NADD Bulletin Volume IV Number 2 Article 1

Complete listing

Sexual Disorders, Developmental Disorders, Developmental Delay, and Co-morbid Conditions

J. Paul Fedoroff, M.D., Beverley I. Fedoroff, B.Sc. (Hons), Kora Ilic


In the past century, conceptions about what constitutes “normal” sexuality have undergone dramatic changes. Masturbation and homosexuality are no longer considered psychiatric disorders. Wide variations in sex drive, sexual fantasies, and behaviors are acknowledged. The importance of assistance in dealing with sexual problems is now universally accepted (Reinish & Beasley 1991). However, for people with developmental delays and/or mental retardation, the pace of change has been slower.

There are several possible reasons for this: misconceptions about the nature of people with developmental delay or mental retardation (summarized in Table 1), care-taker or institutional responses to sexual concerns, and a failure of some therapists to take a truly “multi-dimensional” approach. The purpose of this paper is to review the many ways in which co-morbid or concurrent disorders and living situations can influence the ways in which sex problems are handled in this population.

Potential Effects of Co-morbid Conditions on Sexual Behaviors

To date, most reports conceptualize developmental delay or mental retardation merely as risk factors (vulnerabilities) predisposing sex offenders to relapse (Gilby, Wolf, & Goldberg, 1989; Murrey, Briggs, & Davis, 1992). However, the fact is that individuals with developmental delay or mental retardation are statistically more likely to have problems in many domains—sex is only one of them. Table 2 summarizes some of the conditions that need to be considered in any assessment of sexual disorders.

Autism and Asperger disorder are the two most well-known pervasive developmental disorders. Both are characterized by a deficit in ability to read social cues (Fein, Joy, Green, & Waterhouse, 1996). Since sex is very much a social activity, it is not surprising to find a higher incidence of sex problems in people with these two disorders. Problems in social interaction begin in childhood so that the usual development of gender identity, sexual orientation, and subsequent sexual behaviors typically follow a halting and circuitous course. It is important for experts to bear in mind that an inability to follow social conventions (i.e. asocial behavior) as seen in these two disorders, can easily be confused with antisocial behavior (as seen in criminal sex offenders) (Smolewska, Fedoroff, & Moran, 1999).

A third psychiatric disorder with childhood onset is Attention Deficit Disorder (ADD). Impulsivity, and poor concentration characterize this condition, often with hyperactivity (Barkley, 1997). As with autism and Asperger disorder, the symptoms of ADD interfere with children’s ability to enter into reciprocal social relationships. There is now considerable evidence that it is precisely the experience of learning how to form and maintain social relationships which is crucial to the later formation of healthy adult sexual relationships (Money & Lamacz, 1989).

In contrast, mood disorders, dementia and psychotic disorders all occur more commonly in adulthood (Robinson & Travella, 1996). These disorders cause a dramatic decrease in the previous level of functioning. Their effects are particularly disabling in people with developmental delay or mental retardation. Mood disorders can cause a decrease in sex drive (e.g. Major Depression) or a dramatic increase in sex drive (e.g. Mania). In people who have problems communicating abstract concepts like change in mood, changes in appetite behaviors (eating, sleeping, and/or sexual behaviors) are often the first signs of major depression or mania.

Dementia shares with mental retardation the pathognomonic symptom cluster of global cognitive impairment. However, unlike mental retardation, which is characterized by a failure to develop cognitive abilities, dementia is characterized by a loss of formerly acquired intellectual functioning. Like mental retardation, dementia has many causes and possible presentations. A useful sub-classification divides dementia into cortical and sub-cortical (McHugh & Folstein, 1975). The classic cortical dementia is Alzheimer disease (AD), characterized by aphasia, apraxia, anomia, and global amnesia (Brun & Gustafson, 1999). People with AD often run into sexual problems through mistaking strangers for spouses, making judgement errors (e.g. disrobing in public), and through acting impulsively (e.g. touching a care-taker’s breast). People with Down syndrome, a common cause of mental retardation, have very high risk of developing AD at an early age (Moore & Jefferson, 1996a; Ratey & Dymek, 1996).

In contrast, sub-cortical dementia is characterized by a triad of mood disorder, movement disorder, and cognitive impairment with relative sparing of declarative memory (Sano, Marder, & Dooneief, 1996). A classic disorder associated with sub-cortical dementia is the genetic condition, Huntington’s disease (HD). Some people with this disease have an increased prevalence of paraphilic sexual disorders. One preliminary report has suggested that the sub-group of HD patients more likely to show paraphilic behaviors may be those who first develop inhibited orgasm (Fedoroff, Peyser, Franz, & Folstein, 1994). While there is no association between HD and mental retardation, people with mental retardation are often treated with medications which cause inhibited orgasm. Research is needed on the possibility that the sub-group of people with mental retardation who show paraphilic behaviors have inhibited orgasm, particularly since inhibited orgasm in this population is treatable.

Although certainly not inevitable, psychotic disorders are more prevalent in people with developmental handicaps. The two delusional disorders most often associated with legal charges are erotomania and delusional jealousy. In the former, individuals become delusionally convinced that another person (usually a person outside the likely range of potential suitors) is in love with them (Menzies, Fedoroff, Green, & Isaacson, 1995). In the latter, individuals become delusionally convinced that their spouse is unfaithful (Benson & Gorman, 1996). While there is no evidence that either condition is more common in people with mental retardation or developmental delay, when these conditions do co-occur it can lead to particularly difficult situations.

For example, in one previously unpublished case of the first author, a man in his sixties with mild mental retardation and erotomania became convinced that he was being pursued by a nine year old girl. When he decided to return the girl’s affections, he was charged with sexual interference and referred for presumed pedophilia. On examination, he was found to harbor an additional delusion that he himself was ten years of age!

Much more common for individuals with psychotic disorders is the development of inhibited sexual desire, erectile dysfunction, and/or inhibited orgasm, secondary to the medications used to treat psychosis, especially neuroleptic medications (Segraves, 1996). Individuals with mental retardation or developmental delays are dually at risk, not only because they are more sensitive to medication side effects (Ratey & Dymek, 1996), but also because they have more difficulty communicating with their care takers about sexual problems.

Sexual problems of all sorts are well known to co-occur with anxiety disorders (Charney et al., 1996). This is particularly true for sexual problems involving difficulties in courting and in performing sexual activities. People with mental retardation and/or developmental disorders typically already have difficulties in meeting and approaching potential mates. If they are unfortunate enough to also have an anxiety disorder (e.g. social phobia) their difficulties can increase exponentially.

Paraphilic disorders can all be conceptualized as attempts (consciously or unconsciously) to “short-circuit” conventional courtship and sexual activities. In addition, many paraphilic disorders have been found to respond to medications traditionally used to treat anxiety-related conditions (e.g. social phobia, obsessive-compulsive disorders) (Fedoroff, 1994). Together, these observations raise the possibility that the increased incidence of some paraphilic disorders (e.g. transvestic fetishism) in men with mental retardation or developmental delay may represent an attempt to cope with the extra difficulties they face in having conventional sexual relations. To date, this possibility has not been investigated.

Seizure disorders are common in people with mental retardation or developmental delay (Fein et al., 1996). The stigmatizing effect of epilepsy is often unappreciated. If the person is also forbidden from driving (as is frequently the case in intellectually disabled people) due to mental retardation and/or epilepsy, their social isolation is increased even more. Anti-seizure medications are virtually all known to have side-effects that can cause sexual dysfunctions (Trimble, Ring, & Schmitz, 1996). In addition, there is a sparse but consistent literature suggesting that partial-complex seizures (formerly known as “temporal-lobe epilepsy”) may be associated with unconventional sexual interests, particularly sexual fetishes (Epstein, 1961).

Endocrine disorders are also frequent in people with mental retardation or developmental delay. For example, up to 30% of people with Down syndrome develop anti-thyroid antibodies and hypothyroidism (Moore & Jefferson, 1996a). Hypothyroidism is in turn associated with inhibited sexual desire. Prader-Willi syndrome, associated with mild mental retardation and hypogonadism, is characterized by an insatiable appetite for food but little if any sexual interest (Moore & Jefferson, 1996b). Klinefelter’s syndrome, another genetic condition characterized by hypogonadism, has paradoxically been associated with a higher incidence of paraphilic disorders (although it has a much lower association with mental retardation) (Wakeling, 1972).

Sleep disorders and their association with people who have intellectual impairment is a completely new field. Given that sleep disorders are themselves associated with problems in concentration, irritability, memory impairment, and neuropsychiatric and endocrine disorders, closer investigation of sleep problems in people with mental retardation or developmental delay is long over-due. As an example, a new sleep disorder now known as sleep sex syndrome has recently been identified (Fedoroff et al., 1997). In this syndrome, individuals attempt to engage in sexual behaviors while in slow-wave sleep. The syndrome is readily identifiable with a careful history and sleep study. It also appears to be treatable by correcting the underlying parasomnic sleep disorder. This syndrome has been identified as occurring in people with and without mental retardation or developmental delay. However, given that people with mental retardation or developmental delay have a higher incidence of neuropsychiatric disorders, it is reasonable to hypothesize that there may be a higher incidence in this population. Further studies on this and other treatable sleep problems in people with mental retardation or developmental delay are clearly needed.

Substance misuse (especially alcohol) is frequently associated with both sexual dysfunction and with sex crimes. People with mental retardation or developmental delay are sometimes reported as being less likely than the general population to have substance abuse problems (Ling, Compton, Rawson, & Wesson, 1996). However, this is likely due to the fact that people with mental retardation or developmental delays are more likely to be institutionalized. As more people with mental retardation or developmental delay remain in or return to the community, the incidence of substance abuse can be expected to increase. Given that people with mental retardation or developmental delay are more sensitive to intoxicating substances, attention needs to be devoted to this emerging problem.

Potential Institutional Effects on Sexual Behavior

The preceding section ended with a concern about the increased vulnerability of people with mental retardation or developmental delay who are de-institutionalized. However, institutionalization also carries risks. People with mental retardation or developmental delay, who live in or who spend the majority of their time in supervision, give up privacy. This fact needs to be borne in mind whenever statistics are presented about the prevalence of sexual problems in people with mental retardation or developmental delay. The reason is, unlike psychiatric disorders, the prevalence of which we know a great deal due to epidemiologic surveys, sexual disorders are not among them. None of the major psychiatric epidemiologic surveys (which included non-institutionalized people with mental retardation or developmental delay) have included questions about sexual behaviors or interests. As a result, a great deal of what we know about unconventional sex comes only from studies conducted on institutionalized people (prisoners and/or people with mental retardation or developmental delay living in institutional settings) (Fedoroff & Moran, 1997).

A second problem is that people with mental retardation or developmental delay may be kept in facilities that segregate on the basis of sex (Galton, 1909; Goddard, 1920). This will inevitably alter the sexual behaviors of the “inmates” in ways that may not reflect their natural predispositions. The practice may also interfere with the social learning in this population, which is already challenged. Further, it may increase the likelihood of impulsive acts since opportunities to interact with the opposite sex will be perceived as “fleeting”. If this theory is correct, incidents in which people with mental retardation or developmental delay are caught attempting to have sex in the stairwell or bathroom would be more likely in institutions that do not allow for private meetings.

Recently, there has been growing concern about the possibility that some of the people with the job of caring for people with mental retardation or developmental delay, may taking sexual advantage of them. In Canada, the problem has had sufficient salience to cause a new section of the Criminal Code to be written dealing with “Sexual Exploitation of Person with Disability” (Canada 1998). A corollary of the increased risk of unwanted sexual attention from a person caring for a person who is dependent is the increased risk that the people with mental retardation or developmental delay will develop affectionate feelings toward the caretaker which are not returned. While issues of transference and counter-transference occurring in psychotherapy have received extraordinary attention in the psychoanalytic literature, very little attention has been paid to the potential for these issues to arise between care-takers and their charges.

Institutions or agencies by definition, have regulations. Typically, institutions that care for people with psychiatric disorders avoid putting on paper explicit regulations about sex. However, the unspoken regulation is “the less sex the better.” People with mental retardation or developmental delay quickly get the message. This can result in one of three responses: 1) the message is ignored; 2) the message is obeyed; 3) the message is disobeyed. All three responses eventually lead to problems. In the first case, there will be some random breach of the rules. In the second, attempts to suppress sexual interests will themselves cause their own sexual issues. In the third, sexual activities will occur—this time not only motivated by sexual interest but also by a wish to assert independence. This last situation can be particularly perplexing to agencies, since it can lead to bizarre sexual behavior engaged in by people whom the staff would least expect. A common event is for an individual who is presumed to be heterosexual to begin making sexual comments or overtures toward same-sexed care-takers. This is often extremely upsetting or puzzling to the agency, which fails to recognize that the motivation is not sexual but rather to upset the regulators.

This is not to imply that institutes and agencies necessarily want to be regulating sex. The problem is that the obligation appears to go with the territory. This is because institutes and agencies typically are held fully responsible for the activities (sexual and otherwise) of the people for whom they care. Strategies for dealing with this responsibility need to be developed.

A consequence of the proceeding problems is that people with mental retardation or developmental delay are often isolated to some extent from their care takers, from the community, and from each other. This would be a problem for anyone, but for people who already are challenged in terms of their ability to socialize, read social cues, and express themselves, the difficulties become much greater (Sellings, 1939; Radzinowicz, 1957). Again, individual responses to these hurdles vary: some simply withdraw, some resort to unconventional behaviors, and some rebel.

Finally, it is important to recognize that less than perfect situations can arise in agencies even though no one intends them to do so. Sexual development normally occurs in stages. Children are extremely vulnerable and dependent on their parents to protect them and to provide models of normal social interactions (Perske, 1973). People with mental retardation or developmental delay are more likely to be separated from their parents as children, to find themselves in unusual or age-inappropriate situations, and to be confused by social rules. Adults require independence and privacy in order to come to terms with their sexual interests. They also require the opportunity to meet and socialize with peers and potential mates. Finally, they require privacy with their chosen mate to negotiate, practice, and become comfortable with their sexual behaviors. People with mental retardation or developmental delay often do not get these opportunities and have difficulties managing events when they occur (Goodman, Budmer, & Lesh, 1971; Katz, 1970). The challenge for institutes and agencies is to balance the need to protect and guide with the need to withdraw as the situation demands.


People with mental retardation or developmental delay have more than their fair share of sexual problems. There is no question that people who have difficulties communicating and understanding social cues will have more problems with sex than those who don’t. However, the literature clearly suggests that it is not mental retardation or developmental delay itself which is the problem. Rather, it is the fact that people with mental retardation or developmental delay are more likely to have co-morbid or concurrent problems.

A second point is that not all problems faced by people with mental retardation or developmental delay are medical or psychiatric in nature. In fact, it is arguable that the main problems faced result from the (necessary) interference of natural processes imposed by institutes and agencies (see Table 3).

Modern care of people with mental retardation or developmental delay involves the coordinated efforts of a team of professionals. The process of focussing the attentions of multiple, varied experts on a single problem seem like a very good idea. What could go wrong? The answer is that there is a natural tendency for highly trained professionals to see everything from the angle in which they are most expert—“If the tool in your hand is a hammer, everything tends to look like a nail”. The key is for each expert to recognize that his/her own perspective has strengths as well as weaknesses. McHugh and Slavney (1998) have addressed this issue and suggest four complimentary perspectives. The “disease perspective” pre-supposes that all problems result from a pathophysiologic defect that causes predictable signs and symptoms. Treatment involves fixing the broken part. The “behavioral perspective” presupposes that all problems result from faulty learning. Treatment involves re-training. The “dimensional perspective” pre-supposes that all problems are simply the result of “variance from the (statistical) norm”. Treatment involves either re-framing the problem to include the variance or “pushing” the problem back into the “area under the curve” which is acceptable. Finally, the “life-story” perspective views problems in terms of the meaning it has for the person who has the problem. Treatment involves psychotherapy aimed at making sense of what has happened so those past problems are not repeated.

Each of these perspectives is powerful and useful. However, each has its own limitations. The important point is that none of these four perspectives is mutually exclusive. To the contrary, they are complimentary. For example, a person with mental retardation may score two standard deviations below the norm on an I.Q. Test (dimensional perspective), he may develop Alzheimer disease which impairs his executive functions (disease perspective), he may then discover that he becomes sexually aroused when his nurse rubs his back (learning perspective), he concludes she must be his wife (life-story perspective), and touches her.

The problem can be understood from each perspective and each perspective suggests unique but complimentary interventions. Unfortunately, professionals often lose sight of this fact and “case-conferences” turn into competitions in which the “right” solution is championed by warring experts. People with mental retardation or developmental delay, far from being “simple”, tend to be among the most challenging, interesting, and rewarding people with which health care workers have the privilege of working. The challenge is to remember that the “best” solution will be the one that respects the dignity and uniqueness of the individual while respecting the complementary needs of the people affected by the “solution” (Griffiths, Hingsburger, & Quinsey, 1989).


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For further information:

J. Paul Fedoroff, M.D.
Staff Psychiatrist, Forensic Program &
Assistant Professor of Psychiatry
Centre for Addiction and Mental Health
250 College Street
Toronto, ON, Canada M5T 1R8