El cerebro erótico: rutas neurales de amor y sexo

Adolf Tobeña

Departamento de Psiquiatria y Medicina Legal. Instituto de Neurociencias.

08193 Bellaterra Campus. Universidad Autónoma de Barcelona.

¿EL SEXO MUEVE EL MUNDO?...

“Más tira pelo de concha que yunta de bueyes”, (Popular hispana).

¿EL MOTOR PRINCIPAL DE LOS AFANES Y DESVELOS

HUMANOS?...

- Biólogos = Sexo

- Economistas = Dinero

- Politólogos = Poder

- Publicistas = Notoriedad

- Periodistas = Curiosidad

- Sociólogos = Fútbol

- Religiosos = Esperanza

- Literatos = Mitos

- Filósofos = Sabiduría

- Físicos = Azar

- Artistas = Originalidad

- Cultura popular = Envidia

- Psicólogos, Psiquiatras= (?)…, Perplejos!…

“El cerebro es mi segundo órgano preferido”, (Woody Allen).

SEX IS PLEASANT

…..BUT SOCIALLY

CHALLENGING DUE,

MAINLY, TO ITS

INTERPERSONAL POWER

LINKS…

Georgiadis JR and Kringelbach ML (2012) , Progress in Neurobiology, 98, 49-81

Georgiadis JR, Kringelbach LM and Pfaus JG (2012)

Nature Reviews Urology, 9, 486-498.

Neuroimaging of love: fMRI meta-analysis evidence toward

new perspectives in sexual medicine

Ortigue S, Bianchi-Demicheli F, Patel N, Frum C and Lewis JW (2010), Journal of Sexual Medicine, 7, 11, 3541-3552.

Passion love system

The erotic brain

Sexual Attraction

Desire, impulse

Sexual Orientation

Sexual pleasures

Clímax responses

Romantic Infatuation

Jealousies, Heartbreaks

Maternal/Paternal loves

Friendship attachments

Platonic devotions

Sentimental exploitations …

Mind/brain states subserved by

specific neuroendocrine (complex)

mechanisms

Social affiliation system:

imperfect monogamy, in

humans

SocioSexual rules in Apes

HUMANS:

- Imperfect monogamy

(Serial monogamy,

moderate polyginia..…)

- Preference for a partner +

frequent scanning for

alternatives + collateral

matings

- High behavioural/social

flexibility

monogamous bird‘s mating systems

Meeting with strangers and sex: David Buss (1994)

classical Hawai City study

Questions on casual/brief “spontaneous” encounter:

1. Would you go out on a date with me tonight?

2. Would you go back to my apartment with me tonight?

3. Would you have sex with me tonight?

WOMEN MEN

1. (50%) (50%)

2. ( 6%) ANSWER YES!!! (68%)

3. (0%) (75%)

Prudent vs. Impulsive!!

HUMAN IMPERFECT MONOGAMY/MODERATE POLIGYNIA

1. BIPARENTAL INVESTMENTS (Differences women vs. men)

- Neotenic infants (large period of brain maturation off

utero)

- Extended learning period in childhood

2. BATTLE OF THE SEXES:

- Concealed ovulation in women

- Concealed estrus (heat)

- Extended sexuality (nonrestricted receptivity)

- Feminine/masculine ornaments (attractive signals)

- Mate guarding

- Extrapair copulations (cuckoldry)

CHROMOSOMAL SEX

GONADAL SEX

EXTERNAL GENITALIA SEX

BODY MORPHOLOGY SEX

VOICE SEX

BRAIN SEX

MIND-IDENTITY SEX (Gender)

INTERNAL GENITALIA SEX

MIND-PREFERENCES SEX (Orientation)

Continuities

pathways…,

vs. Variability,

Disparities and

Ambiguities….,

Biological vs.

Environmental vs.

Sociocultural

influences???...

Scatterplot of men (top) and women (down) in

the 2-dimensional space defined by their

attraction to men (x axis) and women (y axis)

Lippa RA (2006),

Psychological Science, 17, 1, 46-52.

1767 subjects (687 males and 1080 females),

mostly Psychology students from California

State University, Fullerton, answering

privately (through internet) valid

questionnaires and scales about sexual

attraction.

HOMO/HETERO

ATTRACTION/PREFERENCES

Erotic brain: motivational/performance systems

Hypothalamic sex-regulating areas:

anterior/preoptic and medial regions

- Sexual identity/orientation

- Sexual motivation/performance

Cameron JL (2004), in RE Dahl and LP Spear

(Eds.): Adolescent brain development, Annals

NYAS, Vol. 1021, 110-123.

Mean youth values of steroid hormones in each sex

Females (N=81) Males (N=102)

Follicular Luteal

DHEAS (ng/ml) 1,32 (0,64) 1,3 (0,62) 2,07(0,93)

AD (ng/ml) 3,8 (2,56) 5,99 (2,78) 0,99 (0,6)

DHEA (ng/ml) 6,24 (6,5) 3,2 (3,4) 1,48 (1,03)

LH (miu/ml) 15,06 (6,17) 30,,57 (17,6) 10,75 (4,8)

T (ng/ml) 0,6 (0,4) 0,73 (0,4) 4,98 (2,56)

TEBG (nmol/l) 57,8 (21,7) 67,4(33,9) 46,75( (13,7)

FTI 0,04 (0,04) 0,04 (0,03) 41,8 (26,6)

P (ng/ml) 1,08 (1,23) 4,53 (5,73) -

E (ng/ml) 0,066 (0,058) 0,19 (0,10) -

DHEA= Dihidroepiandrosterone; AD: Androstenodione; LH: Luteinizing hormone; T= Testosterone;

TEBG=Testosterone binding globuline; FIT= Free testosterone; P= Progesterone; E= Estradiol.

From Udry (1990).

Granger DA et al (2004) Psychoneuroendocrinology, 29, 1229-1240

The erotic brain

Sexual Attraction

Desire, impulse

Sexual Orientation

Sexual pleasures

Clímax responses

Romantic Infatuation

Jealousies, Heartbreaks

Maternal/Paternal loves

Friendship attachments

Platonic devotions

Sentimental exploitations …

Mind/brain states subserved by

specific neuroendocrine (complex)

mechanisms

Social affiliation system:

imperfect monogamy, in

humans

Body form and healthy/young

attributes as a source of sexual

cues

Salient/Appealing

Cues + Neural

Templates for

physical

attractiveness

SEXUAL ADVERTISING QUALITIES OF THE HUMAN

BODY-SKIN

Physical Beauty/Sex appeal variations:

- Age, billateral simmetry

- Race/Ethnicities

- Culture/Fashion ….

Continuities:

- Feminine morph/faces/bodies (estrogenic)

- Masculine morph/faces/bodies (androgenic)

APPEALING ATTRIBUTES OF GENDER’S BODIES MORPHOLOGIES

PUBLICIDAD GOLOSA: SEX APPEAL

Mautz BS, Wong BBM, Peters RA and Jennions MD (2013) PNAS,

110, 17, 6925-6930.

- 343 figurine-videos (frontal/rotated 30º lateral), presented 4 sec., each.

- penises from 5-13 cm. long, flaccid, coming from 3300 italians (an

urological normative sample).

- 105 australian women as judges, 26 years old, 71,8 % whites, rest other

origins. They had to judge 53 figurines appearing by chance at the screen

None ATTRACTIVENESS Maximal

1 7

Am I normal? A systematic review and construction of

nomograms for flaccid and erect penis length and

circumference in up to 15,521 men

Veale D, Miles S, Bramley S, Muir G and Hodsoll J (2015), British

Journal of Urology International, March 3, doi: 10.1111/bju.13010).

Mautz BS, Wong BBM, Peters RA and Jennions MD (2013) PNAS, 110, 17,

6925-6930.

Results:

- Up to 2 attractiveness points can be gained by longer penises, once shoulder-to-hip

ratios and heights controlled.

- 70% variance in attractiveness explained by higher shoulder-to-hip ratios; 10-15% by

penis length (from 10 cm. onwards), and 10-15% by height (1,78-1,87 m, optimum).

- r=0,2 between penis size and women’s inspection times.

- Effects more substantial for taller men.

- Taller and bulky women demand longer penises.

Dixson BJ et al (2010), Archives Sexual Behavior, 39, 798-806.

185 New Zealand and 81 Californian women, 20 years old, judging

Photoshop modified images (penile length or somatic type).

Unattractive 0 Attractiveness 5 Extremely attractive

22%

44%

Neural systems for reward and addiction:

from actions, to habits to compulsions.

Everitt BJ and Robbins TW (2005) Nature

Neuroscience, 8, 1481-9.

Green arrows: Glutamate

Orange arrows: Dopamine

Pink arrows. GABA

ATTRACTION SYTEMS: FACES

Facial testosteronic traits: atractiveness and dominance

Jonhston VS (2006) Trends in Cognitive Sciences, 10, 1, 9-13

Jonhston VS (2006) Trends in Cognitive Sciences, 10, 1, 9-13

b. average face from 117 samples; a. feminized c. masculinized d. hipermasculinized.

Roberts SC et al (2004) Proc. Roy. Soc. London: Biology Letters, 271, S270-S272.

Knut K, Kampe W, Frith ChD, Dolan RJ and

Frith U (2004), Nature, 413, 589-590.

Knut K, Kampe W, Frith ChD, Dolan RJ and

Frith U (2004), Nature, 413, 589-590.

Bare skin + Gaze + Gesture as

salient/sexy cues

Neural systems for reward and addiction: from

actions, to habits to compulsions.

Everitt BJ and Robbins TW (2005) Nature Neuroscience, 8,

1481-9.

Green arrows: Glutamate

Orange arrows: Dopamine

Pink arrows: GABA

Sexual

stimuli

Sex-appeal cues and reward

systems

Fiorino DF, Coury Aand Phillip AG (1995) The Journal of Neuroscience, 17, 12,

4849-4853.

SEXUAL ADVERTISING +

INDUCING QUALITIES OF

THE BODY-SKIN

- Visual cues from a distance

- Direct cues from touch and

taste

- Indirect cues (aware/nonaware)

as smell

Redouté J et al (2000) Human Brain Mapping, 11, 162-177.

EROTIC NEUROIMAGING

Redouté J et al (2000) Human Brain Mapping, 11, 162-177.

Stimuli N= neutral videos; H= Humorous videos; A: nonarousing women

pictures; B: moderately arousing women pictures; C. highly arousing women

pictures; S: Explicit heterosexual coitus videos.

Redouté J et al (2000) Human Brain Mapping, 11, 162-177.

Miyagawa Y et al (2007), Neuroimage, 36, 830-842.

Six healthy heterosexual men, age= 30-39

years, sexually mature (T and semen

measures), had penile recordings and PET

scans while viewing sexually explicit

intercourses (S) vs. control clips (N,M).

Figure: A, B specific activations at the ventral

right putamen during sexual plateau (Sp).

Differences in activation also obtained on the

left anterior hypothalamus, ACC, insula and

right posterior parieto/temporal regions.

Giorgiadis JR et al (2006), European Journal

of Neuroscience, 24, 3305-3316.

12 heterosexual women

volunteers, mean age 34

years, range 21-47,

accompanied by their

partners who manually

stimulated them during

the PET scan sessions.

In addition to main effects (Figure),

there were specific results in the

contrasts Stim vs. Rest, Orgasm vs.

Rest and Orgasm vs. Stim.

Giorgiadis JR et al (2006), European Journal of Neuroscience, 24, 3305-3316.

Positive correlations between

sexual arousal (perceived)

and rectal pressure with

regional blood flow PET-scan

measures.

Significant level in this figure is P < .001.

Superimposed on T1-weighted MR

standard single subject image from

SPM99.

Brunetti M et al (2008), European Journal of Neuroscience, 27, 2922-2927.

Brunetti M et al (2008),

European Journal of

Neuroscience, 27,

2922-2927.

Georgiadis JR, Kringelbach LM and Pfaus JG (2012) Nature Reviews Urology, 9, 486-498.

Stoleru S, Fonteille V, Cornélis CH, Joyal Ch and Moulier V (2012),

Neuroscience and biobehavioral reviews, 36, 1481-1509.

The erotic brain

Sexual Attractions

Desire, impulse

Sexual Orientation

Sexual pleasures

Clímax responses

Romantic Infatuation

Jealousies, Heartbreaks

Maternal/Paternal loves

Friendship attachments

Platonic devotions

Sentimental exploitations …

Mind/brain states subserved by

specific neuroendocrine (complex)

mechanisms

Social affiliation system:

imperfect monogamy, in

humans

EROTIC/ROMANTIC INFATUATION

Falling and being in love

- Intense attraction

- Neurogonadal urges

- Exaggerated Mood Oscillations (Euphoria/desperation)

- Perceptual/affective interpersonal fusion (folie a deux)

Function

Neuroendocrine Tempest to strengthen monogamous

binding (transient vs. long-lasting)

Intensity

1 2 3 4 Time (Years)

Love/sex kynetics: Passion (red); Loss Aversion (purple);

Affect/companionship (green)

Hormonal changes when falling in loveMarazitti D and Canale D (2004)

Psychoneuroendocrinology, 29, 931-936.

Depts. of Psychiatry and Endocrinology, Pisa University, (Italy).

Hormonal changes when falling in loveMarazitti D and Canale D (2004)

Psychoneuroendocrinology, 29, 931-936.

When subjectes were retested 12-24 months later no

differences remained!!!

Neurogonadal cascades: main stars

Desire/Sexual drive:

Testosterone, dihidrotestosterone, androstenodione, others…

Appeal/Atractiveness:

Dopamine, androstens, copulins...

Satisfaction, sexual pleasure:

Opioids, oxytocine…

Possession/Jealousy:

Vasopressine, serotonin…

Affection/attachment/companionship:

Oxytocine, prolactine, endozepines …

Memories of affective pleasures:

Glutamate, nitric oxide……

Love/Sex profiles dependent

on these different

neurohormonal systems.

Men/Women differences!!!

Prairie voles: a model for monogamous

fusion/affect

Ethology of pair bonding:

Lowell Getz, Sue Carter

and Carroll Horbaugh

Neurobiology of Affective

Attachments:

Larry Young and Thomas

Insel

Illinois University-Urbana/Champaign and

National Institutes of Mental Health,

Bethesda, Washington DC.

Prairie voles: ethology of monogamous fusion

OXYTOCIN RELEASE AND STIMULATION

Donaldson JR and Young L (2008), Science, 322, 900-904.

Pair bonding neurochemistry in

Prairie Voles

Partner preference test

A neurochemical map of pair-bonding

mechanisms in monogamous voles

From detailed neuroanatomy to transgenic/transpecies manipulations

Donaldson JR and Young L (2008), Science, 322, 900-904.

Donaldson JR and Young L (2008), Science, 322, 900-904.

Walum H et al (2008) PNAS, 105, 37, 14153-14157.

552 twin pairs and their spouses

(Swedish Registry), mostly white

middle class, born between

1944-1971. 82% married and 18%

cohabiting. 238 MZ.

Okhovat M, Berrio A, Wallace G, Ophir AG and Phelps SM (2015),

Science, 350, 6266, 1371-1374

25% pups from extrapair matings

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Neuroimage (2004), 21, 1155-1166

Procedure:

20 Mothers, 34 years age (27-40) provided photos of their own child (oc) or an

acquainted child (ac) same age (9months-6 years, mean 24 months).

Also provided photos of a best friend (all females: 36,9 years age, relationship time > 15

years)

fMRI sessions in a 2T Siemens equipment.

Subjects only had to view the photos and relax

Pictures presented on a screen, in pseudorandom order, against a gray background, in a

passport format.

Each picture presented 6 times for 15 sec.

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Wellcome Department of Imaging Neuroscience, University College London, London, UK

Neuroimage (2004), 21, 1155-1166.

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Neuroimage (2004), 21, 1155-1166

Maternal love activations: viewing own child vs. acquaintance child same age

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Neuroimage (2004), 21, 1155-1166

Contrasting maternal (n=19) versus romantic (n=17) women

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Neuroimage (2004), 21, 1155-1166

Specific and Overlapping areas

Maternal and romantic love: Summary of fMRI ACTIVATION resultsBartels A and Zeki S (2004), Neuroimage, 21, 1155-1166

Specific of Maternal love:

PAG

Lat. Orbito-frontal cortex

Lat Fusiform gyrus

Frontal eye fields

Dorsal Occipital cortex Shared by both Maternal/Romantic Love:

Insula medial

Anterior Cingulate

Caudate, putamen

Specific of Romantic Love: Subthalamic nucleus

Hypothalamus G. Pallidum

Dentate gyrus Substantia Nigra

Ventral Tegmental Area

The neural correlates of maternal and romantic loveAndreas Bartels and Semir Zeki

Neuroimage (2004), 21, 1155-1166

Same deactivated areas: maternal (oc-ac) and romantic (lover – friend)

Maternal and romantic love: fMRI DEACTIVATED areasBartels A and Zeki S (2004), Neuroimage, 21, 1155-1166

In both Maternal and Romantic Love:

Middle Prefrontal Cortex **

Parietal Cortex

Medial Temporal Cortex

Temporal Pole Thinking and warning systems

Posterior Cingulate *

Medial Precuneus

Amygdala **

Regions rich in

Oxytocin and

Vasopressin receptors:

fMRI activations

Maternal and romantic loveBartels A and Zeki S (2004), Neuroimage, 21, 1155-1166

Acevedo BP, Aron A, Fisher HE and Brown LL, (2012) SCAN,7, 145-159.

Acevedo BP, Aron A, Fisher HE and Brown LL, (2012) SCAN,7, 145-159.

Amadei EA et al (2017) Nature,

Neuroimaging of love: fMRI meta-analysis evidence toward

new perspectives in sexual medicine

Ortigue S, Bianchi-Demicheli F, Patel N, Frum C and Lewis JW (2010), Journal of Sexual Medicine, 7, 11, 3541-3552.

Passion love system

Neurogonadal love/sex cascades: main stars

Desire/Sexual drive:

Testosterone, dihidrotestosterone, androstenodione, others…

Appeal/Atractiveness:

Dopamine, androstens, copulins...

Satisfaction, sexual pleasure:

Opioids, oxytocine…

Possession/Jealousy:

Vasopressine, serotonin…

Affection/attachment/companionship:

Oxytocine, prolactine, endozepines…

Memories of affective pleasures:

Glutamate, nitric oxide…… Love/Sex profiles dependent

on these different

neurohormonal systems.

Individual differences in

motivation, pleasure,

preferences and intimate

affect!!!

El cerebro erótico: rutas neurales de amor y sexo

Barcelona: La Esfera de los Libros, 2006