Sex: The Altered State of Consciousness

1
Sex The Altered State of Consciousness

• COGS 175, June 5th 2006
• Part I
• Cody Frew, Rachel Jaffe, Rajiv Rao
• Part II
• Katie Frehafer, Dan Hoag, Josh Kirsch, Brian
  Waldberg

2
Topic Outline

• Group I
• Intro - Cody, Rachel, Rajiv
• Neurochemicals - Rachel
• Arousal Pathways - Rajiv
• Hormones / Baseline States - Cody
• Group II
• Pheromones / Attraction - Josh
• Biological Changes - Katie
• Sexual Abnormalities - Brian
• Masochism Dan Hoag
• Conclusion Josh, Katie, Brian, Dan

3

• Warning

contains explicit material
4
Introduction

• Is sex an altered state of consciousness?
• Yes
• Many changes take place during sexual arousal and
  intercourse that deviate from the normal waking
  state of consciousness.
• Neurochemical changes
• Hormonal changes
• Changes in brain activation
• Changes in the biological state of the body
• Social behavior and interactions that are limited
  to sexual states

5
Neurochemicals of Sex

• Neurotransmitters and Neuropeptides involved in
  sexual function
• Nitric Oxide (NO)
• Serotonin (5-HT)
• Dopamine (DA)
• Epinephrine
• Norepinephrine (NE)
• Opioids
• Acetylcholine (Ach)
• Histamine
• ?-Aminobutyric Acid (GABA)

6
Nitric Oxide (NO)

• Key factor in production of penile/clitoral
  vasocongestion and tumescence.
• Sexual stimulation ? NO production ? Guanylate
  Cyclase
• Guanosine Triphosphitase (via Guanylate Cyclase)
  ? cGMP
• cGMP relaxation of smooth muscles genital
  arteries resulting in increased blood flow to
  those areas.
• cGMP is metabolized by cyclic nucleotide
  phosphodiesterase isoenzymes.
• As long as stimulation continues, metabolic
  degradation is balanced by production and arousal
  is maintained.

7
Serotonin (5-HT)

• Selective Serotonin Reuptake Inhibitors (SSRIs)
  effects 5-HT activity and causes sexual side
  effects.
• Increased 5-HT causes decreased libido.
• 5-HT2 receptor stimulation impairs sexual
  functioning.
• 5-HT1a receptor stimulation facilitates sexual
  functioning.
• 95 of 5-HT receptors are located in the
  periphery of the body.
• Peripheral 5-HT acts on
• smooth muscle vasodilation/vasoconstriction,
  including the smooth muscle of the genitals.
• peripheral nerve functions, including those of
  the sexual organs.

8
Dopamine (DA)

• DA facilitates male sexual behavior
• D1 and D2 receptor agonists increase sexual
  activity and induces erection.
• Common DA agonists Apomorphine and L-Dopa
• Moderate doses of cocaine, which blocks the
  reuptake of DA, can increase sexual pleasure, but
  also inhibit sexual behavior in the withdrawal
  phase.

9
Epinephrine

• Adrenergic activity has a role in maintaining the
  penis in a flaccid state and reducing swelling.
• Blockade of the a1-adrenergic receptors produces
  erection.
• Adrenergic agonists, like Ephedrine, increase
  vaginal pulse amplitudes in response to erotic
  stimuli.
• Adrenergic system activates when sexual arousal
  begins, and epinephrine increases until its peak
  at orgasm.

10
Norepinephrine (NE)

• Blood plasma levels of NE increase during sexual
  activity.
• NE levels positively correlate with arousal,
  peaking at orgasm and then returning to baseline.
• NE levels return to baseline within minutes for
  males, while it can take up to 23 hours for
  females.

11
Opioids

• Role in sexual function is studied by looking at
• Endogenous opioids (endorphins, enkephalins,
  dynorphins).
• Narcotics (opiates)
• Abuse of opiates leads to sexual difficulties.
• Opioid anatogonists (naloxone and naltrexone)
  used to treat erectile dysfunction.
• Exact role of endogenous opioids in normal sexual
  functioning is unclear, but levels are thought to
  increase during sexual activity.

12
Acetylcholine (Ach)

• Ach is involved in the sexual function of males
  much more than females.
• Ach stimulates the cholinergic receptors in the
  penile tissue to act as a key factor in producing
  erection.
• Penile erection is controlled by the Ach levels
  in the CNS, regardless of cholinergic receptors
  in the periphery.

13
Histamine

• Histamine antagonists tied to loss in libido.
• Due to decrease in uptake of testosterone.
• Administering histamine counters some cases of
  impotence.
• Possible action on H2 and H3 receptors.

14
?-Aminobutyric Acid (GABA)

• Effects only studied in male rats
• Inhibits sexual behavior (mounting, intermitting,
  erection, ejaculation)
• Possibly correlates to GABA effects in human
  sexual function.

15
Arousal Pathways

• Connectivity in the Brainstem and Spinal Cord
• Neurological Substrates Involved in Sexual
  Activity and Arousal

16
(No Transcript)
17
Arousal Pathways

• Connectivity in the Brainstem and Spinal Cord
• The Nucleus Paragigantocellularis ? lumbosacral
  spinal cord of both males and females.
• lumbosacral spinal cord ? ascending reticular
  activating system.
• The Raphe Nuclei (5-HT) ? lumbosacral spinal cord
• Magnus and Parapyramidal regions ? lumbosacral
  spinal cord
• Locus Ceruleus (NE) ? lumbosacral spinal cord

18
Arousal Pathways

• Connectivity in the Brainstem and Spinal Cord
  (continued)
• Further evidence shows that the Periaqueductal
  Grey Area of the midbrain acts as a relay center
  for sexually relevant stimuli.

19
Arousal Pathways
20
Arousal Pathways

• Neurological Substrates Involved in Sexual
  Activity and Arousal
• Hypothalamus
• Lesions to the Medial Preoptic area
• The Paraventricular Nucleus (PVN) of the
  hypothalamus shows activation in both sexes
  during copulation in rats.
• Oxytocin precursors released from PVN

21
Arousal Pathways

• Neurological Substrates (continued)
• Medial Amygdala
• Bed Nucleus of Stria Terminalis
• EEG studies have shown that right-to-left
  hemispheric asymmetry occurs during nocturnal
  penile tumescence.

22
Arousal Pathways

• Neurological Substrates (continued)
• Right prefrontal cortex activity during the
  viewing of sexual stimuli.
• Bilateral rCBF increases in the inferior temporal
  cortex, right insula, right inferior frontal
  cortex, as well as the left anterior cingulate
  cortex.
• Largest rCBF increase occurred in cerebellum

23
Arousal Pathways

• Neurological Substrates (continued)
• Activation of the mesodiencephalic transition
  zone, as well as the ventral tegmental area
  during ejaculation in males.
• Activation in midbrain lateral central tegmental
  field
• Zona incerta, subparafascicular nucleus, and the
  ventroposterior, midline, and intralaminar
  thalamic nuclei (all to a lesser extent than the
  ventral tegmental area).

24
(No Transcript)
25
Hormones/Baseline states

• Hormone Greek for to activate
• What do hormones have to do with sex and the
  altered state of consciousness?

26
Hormones/Baselines

• Endocrine System
• Anatomy
• Adrenal glands
• Pituitary gland
• Hypothalamus
• Testes (male)
• Ovaries (female)
• Placenta (pregnancy)
• Seen in all mammals- Must be important to
  survival.

27
Hormones/Baselines

• What are some of the hormones related to the ASC
  of sex?
• Pituitary hormones
• Gonadotropins
• Follicle-stimulating hormone (FSH)
• Luteinizing hormone (LH)
• Prolactin
• Oxytocin
• Adrenal hormones
• Androgens
• Estrogens
• Steroids

28
Hormones/Baselines

• Hormones play a vital role in overall mood,
  arousal, desire, coitus, and even post-coital
  behavior
• E.g. Oxytocin the cuddle hormone

29
Hormones/Baselines

• How do hormones play a role in brain function,
  sex, and consciousness?
• Constant interaction within endocrine system and
  brain
• Hypothalamus Feedback Mechanism
• Gn-RH
• Gn-IH
• Excessive estrogen ? sexual desire (both M F)
• Testosterone ? sexual desire (both M F)

30
Hormones/Baselines

• Hormone Configurations/Baseline States
• Effect on Cognition
• higher testosterone levels has been correlated
  with higher performance on spatial intelligence
  tasks, but lower performance on verbal
  intelligence tasks.

31
Hormones/Baselines

• Timelines
• Lifetime (male- testosterone)

32
Hormones/Baselines

• Monthly (female) Daily (male)

• Males seem to have higher levels of testosterone
  in the morning, compared to the rest of the day.

Different hormonal states are constructed that
serve as baselines for motivation, perception,
cognition, and behavior.
33
Hormones/Baselines

• Gender Differences
• Same chemicals but different
• Amounts
• Proportions
• Physical anatomy!

The Female Brain
The Male Brain
34
Hormones/Baselines

• Questions
• Who controls sexual behavior? Is it you or your
  hormones???
• The hypothalamus monitors and helps maintain
  various hormone levels within the body that is
  deemed appropriate but who tells the
  hypothalamus what is appropriate?!?
• Is it possible to moderate your hormones with
  deliberate conscious thought?
• Biofeedback perhaps!

35
(No Transcript)
36
Works Cited (Group I)

• Arnow, Bruce et. al. Brain activation and sexual
  arousal in healthy, heterosexual males Brain.
  Vol. 125, No. 5, 1014-1023, May 2002.
  http//brain.oxfordjournals.org/cgi/content/full/1
  25/5/1014
• Holstege, Gert et. al. Brain Activation During
  Male Ejaculation. The Journal of
  Neuroscience, October 8, 2003, 23(27)9185-9193
• http//www.jneurosci.org/cgi/content/full/23/27/9
  185
• McKenna, K. The Brain is the master organ in
  sexual function CNS control of male and female
  sexual function. Int. J Impot. Res. 199911
  (suppl 1)S48-S55
• Meston, Cindy et. al. The Neurobiology of Sexual
  Function Arch Gen Psychiatry, Vol. 57. American
  Medical Association. Nov 2000. http//www.usfca.ed
  u/fac_staff/dever/neurobiologyofsex2.pdf
• Fundamental Neuroscience, 2nd edition. Ch. 35, p.
  928-933. Ch. 40, p. 1031-1036. Academic Press,
  San Diego, 2003.
• Allgeier, ER, Allgeier, AR.  Sexual Interactions,
  5th Edition.  Houghton Mifflin Company, Boston,
  New York.  2000.
• Gangestad S.W., et al. Women's Preferences for
  Male Behavioral Displays Change Across the
  Menstrual Cycle. Psychological Science, Volume
  15, Number 3, March 2004, pp. 203-207(5)
• Christiansen, K., Knussmann, R. Sex hormones
  and cognitive functioning in men.
  Neuropsychobiology, 18 27 - 36. 1987
• Sanders, R. Brain hormone puts brakes on
  reproduction. February 2006. http//www.berkeley.
  edu/news/media/releases/2006/02/06_hormone.shtml