Sexology

Gender

the roles of cis and trans (any gender constructed in society)

Sexuality

sexual feelings, thoughts, attractions and behaviours towards others

Sexual behaviour

behaviour that produces arousal and increases chances of orgasms

Sexual identity

how one defines themselves with regard to sexual/romantic interests

Sexual orientation

what one actually does and likes

Sexual health

the ability to sexually adapt and self-manage in the face of life’s physical, psychological and social challenges

Sexual rights

basic inalienable rights regarding sexuality

Sexology

scientific study of human sexuality from bio-psycho-social perspective

Purpose of sex

→ progeny

→ please (bonding)

→ money/business

Sources of knowledge regarding sex

→ innate/own experience

→ family and friends

→ school, religion, government

→ media

→ health care professionals

Consequences of bias sex source

→ heteronormativity

→ norms in orgasms

→ shame and stigma

→ women tend to report lower numbers of sexual partners

Gametic union

union of sperm and egg

Sex (lit)

sexual anatomy and behaviour

Gender

male/female/trans - often gender binary

Communication theorists: 3 types of media influence

1. Cultivation Theory

2. Framing Theory/Agenda Setting

3. Social Cognitive Theory

Cohabitation

if you finish university, you’re more likely to marry the first romantic partner you live

longevity and sex

sexual activity inversely related to mortality and intimacy

Psycho-neuro-endo-hemo (vascular) dynamics

Desire

• hormones

• nerve/neurotransmitters

• clitoris and penis have the same arousal

Excitement arousal

• circulation

• nerves/neurotransmitters

Orgasm

• nerves/neurotransmitter

• women can have only one, multiple, or no orgasm

Most important organs in sex

skin and brain

Gonads

primary reproductive organs

women: ovaries

men: testes

Development of Gonds

→ female development is the default

→ development depends on the presence of SRY gene (always on Y chromosome)

→ present SRY (sex-determining region) gene = testes

Sex development of gonads

• in males @ 7th week, outer portions of gonads degenerate and inner portions develop into testes

• in females @ 11th week, inner portions of gonads degenerate and outer portions develop into ovaries

Puberty

Development of Secondary sex characteristics

→ occurs when hypothalamus begins to secrete gonadotropin-releasing hormones (GnRH) causing pituitary to release

→ LH and FSH

Sexuality and 3 brain system

1. limbic system

2. hypothalamus

3. genital reaction

Limbic system and sexuality

important for controlling behaviour for survival

Hypothalamus and sexuality

hunger and thirst, circadian rhythm and sex (controller autonomic and endocrine output with different core regions)

Genital reaction and sexuality

Core regions in the hypothalamus project directly or via core regions in the brainstem into autonomous neurons in the spinal cord

Neurobiology of sexual drive and function

1) software - role of hormones, neurotransmitters and neuromodulator

2) hardware - how neural network process and modulate sexual responses

Dual control model

→ whether sexual desire increases from hormones or not, the mental state plays a part

→ as well as psychosocial, cultural and behavioural

Relevant innervation/vascularisation of penis

dorsal nerve → sensitivity

pudendal artery → function

Male sexual response stages

1. excitement phase

2. plateau phase

3. orgasmic phase

4. resolution phase

Erection types

1. psychogenic erections

2. reflexogenic erections

3. nocturnal erections

Psychogenic erections

→ the cortex which influences sacral centres and through hypogastric center creating of erection

Reflexogenic erection

→ signals from penis to pudenda nerve and to sacral region through reflex hypogastric plexus to the corpora of penis

Nocturnal erection

→ reflexogenic during REM sleep

Mechanism of erection

1. erotic stimuli: key neurotransmitter for erection: dopamine

2. neural initiation: parasympathetic oxytocinergic nerve fibres

3. cellular activated: activation of NO-L-Arginine cGMP pathway

   • PDE 5 releasing NO

4. relaxation of cavernous smooth musculature

5. erection

Role of Nitric Oxide

Stimuli → NO released → cGMP formation → vascular smooth muscle relaxation → influx of blood into sinusoids

Veno-occlusive mechanism in penile erection

→ penis and clitoris is the only organ in the body that moves from flaccid to erection

→ more blood goes in (arterial influx) and less blood comes out (venous efflux)

Erection enemies

• Smoking - atherosclerosis, build-up of plaque and fatty materials in arteries

• Alcohol - affects blood vessels and nerves responsiveness

• Drugs - heart problems, irregular blood pressure, mental health

• Stress - effects of cortisol and adrenaline

• Obesity - atherosclerosis, build-up in arteries

Deadly Quartet

1. diabetes

2. obesity

3. hypertension

4. dyslipidemia (high cholesterol)

→ endothelial dysfunction (blood) → cardio vascular diseases and erectile dysfunction

Ejaculation

→ outcome of sexual arousal

→ often occurs simultaneously with orgasm

→ induced by nerve stimulation

→ expulsion of semen from outer urethral orifice

Anatomy involved in ejaculation

Brain - Spinal cord - Peripheral nerves (dorsal/pudendal nerve)

Composition of ejaculation

Volume (1.5-5 ml) = seminal vesicle (50-70%) + prostate (15-30%) + ampula vas deferens, cowper glands, urethral glands (<5%)

Cerebral control of ejaculation: key supraspinal centres

thalamus → hypothalamus (paraventricular nucleus + medial preoptic area) → midbrain (periaqueductal grey) → pons (nucleus paragigantocellularis)

Neurotransmitters and ejaculation

• serotonin (5-HT)!!!

• dopamine (DA)

• gamma-aminobutyric acid (GABA)

• noradrenalin

  → sympathetic process

Average time of ejaculation

5 minutes - from penetration to ejaculation

Pelvic floor: 3 function

1. supports bladder

2. part of sphincters mechanism

3. birth process

“complex web of muscle, fascia and fibrous tissue”

Pelvic floor: so much more

→ support

→ passage

→ mobility/stability

→ sex (respond to arousal and enhance enjoyment)

→ emotion

PF: hammock analogy

Involvement of pelvic floor

→ Enhancement of blood flow - ischiocavernosus muscle facilitates erection, bulbocavernosus maintaining the erection

→ inhibit ejaculation relaxation of bulbocavernosus and ischiocavernosus muscles

PF overactivity

• dyspareunia

• genital pain (vulvodynia, orchialgia, prostatodynia, radiating pain penis)

• orgasmic pain, obstructive ejaculation

• non-disappearing swollen feeling in the genitals (PGAD)

Sexual differentiation

Conditions for healthy sexual development

• matching gender identity

• women pedagogical climate

• positive examples/messages of relations and sexuality

• possibility to age-specific consensual sexual practice behaviour

• skin contact

Puberty: secondary sexual characteristics

Onset:

• men - first ejaculation

• women - first period, breast

• hair in pubic area

Hormones and sex

hypothalamus → GnRH

anterior lobe of pituitary → LH and FSH

gonads → estrogen, testosterone, progesterone

Fertility timeline

born - 1 million

puberty - 400,000

every ovulation - 1-2

menstruation - 400

Normal female organs variation

glans clitoris - 0.5-3.5 cm

vagina - 6.5-12.5 cm

hymen - 1-2.5 cm

labia minora - 0.7-5 cm

Labia

width: 7-50 mm

→ different lip sizes

→ congenital abnormal inner labia

• NVOG guideline

• mot interventions are cosmetic

Clitoris

8-10cm

→ only organ for sexual pleasure purpose

→ clitoris can act as pads during intercourse

Vaginaal vestibulum

→ sensitive lubrication (protection)

Internal genitals

Uterus - womb 6-7 cm length

Ovarium - ovary 1.5×2.5 cm

Tuba - fallopian tube max 5 cm

Genital arousal

→ increase in genital blood flow

• transudate: lubrication from vagina wall

→ swelling of vulva and clitoris

→ erection and retraction of glans clitoris

→ elongation of vagina and ballooning

→ transudate: lubrication

→ rise of uterus

Physiology of sexuality

Peripheral responses

→ cardiovascular: heart beat increase

→ respiratory tract: frequency increase

→ skin: sex blush??

→ stiffness of nipples

Physiology of sexuality: orgasm

→ intense feeling of pleasure

→ some degree of altered consciousness

→ specific sensations in genital region and pelvis

→ muscle contraction in PF and uterus

→ other reactions: rhythmic movement, vocalisation

Congenital abnormal external genitals: hymen

intercourse not possible = primary vaginismus

→ hymen string

→ imperforate hymen

Other clinical problems: female genital

→ ovarian cyst

→ myoma/fibroid

→ vulvar carcinoma

Female genital mutilation (FGM)

→ >200 million girls

→ age 4-12 years

→ 30 countries in Africa, ME and Asia

→ mix of sociocultural factors within families and communities

→ nor religion association

→ views on clean, purity, beauty, femininity

4 types of FGM

1. clitoridectomy

2. excision

3. infibulation

4. all other harmful procedures

Congenital disorder of development: MRKH syndrome

Mayer-Rokitansky Kuster Hauser Syndrome

→ 46xx

→ no menstruation

→ infertile

→ intercourse not possible

Disorder of sexual development: AIS

Androgen Insensitivity Syndrome

→ 46XY

→ no hair (armpit/pubic)

→ external genitals are female

→ vaginal and uterus agenesis

→ no menstruation

→ infertile

Disorder of sexual development: AGS

Adrenogenital syndrome in women

→ 46xx

→ enzyme defect 21-hydroxylase

→ internal genitals female

→ clitoral hyperplasia

→ high testosterone levels

→ autosomal recessive

→ adrenal hyperplasia

Rate of penetrative orgasm

30%

→ due ot clitoris anatomy

Early sexual development

0-4: discovering your body (touching)

4-6: learning about social rules, first friendship

7-9: shame, fantasies and first infatuation

10-15: puberty

16-18: adolescence

18+: adulthood

Sexuality education

much more than sexual intercourse:

→ biological: body, reproduction, health

→ psychological: emotions, experience, thoughts, mental wellbeing

→ social: gender, education, expectation, culture, peer group

Principles comprehensive sexuality education

based on…

• age

• human rights

• scientific facts

• needs

• positive approach

• gender equality

• view humans as sexual beings?

• culturally sensitive

• bio-psycho-social approach

Measuring sex

→ questionnaire

→ psychophysiological studies

Specific physiological sexual responses

Men

→ increase in volume of corpora cavernosa, erection

Women

→ increase in volume of corpora cavernosa, increase in blood flow to vaginal wall thus lubrication

Barlow strain gauge

→ assess different circumferences of the penis

Photoplethysmograph

→ assess changes in vaginal blood flow

Erotic stimuli

• fantasy

• tactile

• photography

• erotic film

Issues in psychophysiological sex research

• objective assessment

• small samples (selection bias)

• ethics (private, intimate subject)

Automatic response to sex?

→ after an erotic film, the response is fast (increase in vaginal blood flow)

→ regardless of whether they are feeling aroused or not (and age)

Ledoux and Damasio

Emotional stimulus → sensory thalamus …..

"quick and dirty pathway →> amygdala

“neat and slow” pathway → sensory cortex +hippocampus → amygdala

fMRI study:sexual stimuli activate emotion motivation system?

→ is it influenced by dopamine?

→ 53 healthy young men

→ 3 groups: levodopa (high dopamine), haloperidol (low dopamine), placebo

→ unconscious sex stimuli

fMRI study: sexual stimuli activate emotion motivation system? - results

recognition task:

• percentage of correct classification was below chance level

• target picture was not consciously perceived

brain activity:

• activation in ACC and nucleus accumbens

• this was stronger with more dopamine

genital x sexual arousal correlations

men: high

women: low

hypothesis: womens sexual feelings are determine by evaluation of context rather genital response

Meaning of stimulus: study by Laan

• meaning of sexual stimulus: regular vs women-oriented

• film excerpt matched in terms of nature duration of portrayed sexual activities

• measure genital and sexual arousal response in men and women

Meaning of stimulus: study by Laan - result

genital response:

• no significant difference in genital response between films (for both genders)

subjective sexual response

• men: sexual feelings equally strong

• Iwomen: stronger for women-oriented film

Unconscious activation: implications

1. motivation process has been activated before the individual is conscious

   • helps understand why sexual response can be difficult to control

   • pharmacological regulation?

2. research on relationship between genital - subjective

   • automatic genital response is not evidence of positive sexual experience

   • reduced sexual arousal does not indicate disturbed genital response

   • meaning of stimulus is important (women)

   • viagra for women does not work

Criteria for diagnosing sexual disorder

• must cause significant distress

• must occur on 75-100% of occasions

• minimum duration of 6 months

Presentation of sexual complaints (women)

Female sexual arousal disorder

lack of:

• interest

• sexual thoughts/fantasy

• initiation of sexual activity

• sexual excitement

• arousal to erotic cue

• genital sensation

Gender difference in sex

• men masturbate more

• they fantasise more often about sex

• experience sexual desire more often

• report less often problems in lack of desire

Prevalence of problems in women

• lack of sexual desire: 20-30%

• sexual arousal problems: 11-31%

• sexual distress as a criterion: decrease of 50%

• high co-morbidity of desire and arousal problem

Orgasmic disorder

• delay in, infrequency of, or absence of orgasm

• reduced intensity of orgasmic reactions

Prevalence of female orgasmic problems

• problems reaching orgasm: 3.5-35%

• only 25-30% reach orgasm during intercourse

Etiology: Incentive motivation model (Toates)

Stimulus → (memory→sexual motivation←physical state) → behaviour and genital response/feelings

*regulation and inhibition plays a part

Arousability and effect

Hormone levels → cancer ovaries, surgical menopause

Somatic diseases → neurological and endocrine disorder

Medication → SSRI, anti-psychotics, anti-androgens

Arousability of healthy women with disorder (Laan)

• laboratory study with healthy control vs sexual arousal disorder

• genital and subjective sexual response to film

• using photoplethysmography

Arousability of healthy women with disorder (Laan) - results

• no difference in genital response

• report lower subjective sexual response

• but no difference in negative response