Introduction to Biopsychology [PSB 4002]

1. Introduction to Biopsychology[PSB 4002] Professor Robert Lickliter DM 260 / 305-348-3441 licklite@fiu.edu website: dpblab.fiu.edu

2. Learning (focus of Ch. 11) • Learning is a dimension of both physiology and behavior • Learning is not separable from a behaving body

4. Memory • MEMORY: involves at least three activities -acquire a piece of information -retain the information -retrieve the information

5. Memory • In the late 1940’s, Donald Hebb proposed that learning and memory must involve changes in the relationship betweensynapses, where neurons meet and communicate with one another. • This idea eventually led to the notion of long-term potentiation (LTP), the increased ease with which neurons send messages to other neurons after being stimulated repeatedly.

6. Memory • The density of dendritic branching is obviously related to the number of synapses available. • Enrichment studies with a variety of animals have shown that enriched experience can lead to the development of increased numbers of synaptic contacts and more complex networks both in the cortex and in other regions known to be involved in learning and memory (hippocampus for example).

7. A wealth of studies starting back in the 1950’s on the effects of early handling, enriched rearing environments, responsive maternal care, etc. have highlighted the power of early experience to later physiological and behavioral outcomes initial conditions

10. Brain Systems • Brain systems involved in memory include: • cerebellum • hippocampus • limbic system (amygdala) • cortex (particularly prefrontal) • These systems work together to allow:  • sensory memory • working memory (short-term memory) • long-term memory (including autobiographical memory)

11. The Curious Case of Infantile Amnesia

12. Infantile Amnesia • In addition to obvious issues of brain growth and myelination, research has shown that moving out of infantile amnesia has to do with the relationship between (a) the development of a cognitive sense of self and (b) the personalization of event memory

13. Memory • The curious case of infantile amnesia has led researchers to appreciate that there are memory systems for “what” and for “how” and while related, have a number of important differences

14. Memory

15. Autobiographical Memory • Autobiographical Memory: • is explicit and declarative • involves a sense of self experiencing the event at a specific point in time and space • is personally significant, concerned with episodes that have personal meaning

16. Interestingly, autobiographical memory appears to emerge gradually across the pre-school years through complex processes of social interaction and cognitive development (meaning you did not always have this type of memory).

17. Neural Plasticity and Learning

18. Autobiographical Memory • It seems to require: • basic memory systems • the acquisition of complex language • narrative comprehension and production • temporal understanding • representation of self • memory talk with parents and others

20. Human Sexual and Reproductive Behavior • humans are non-seasonal breeders • human females are concealed ovulators • sex is not only for reproduction

21. Puberty • Set in motion during prenatal development and the organizational effects of the steroid hormones on brain structure and function • Onset of puberty has undergone dramatic change over the last several centuries (but why?)

22. Hormonal Mechanisms • At the onset of puberty, the hypothalamus begins to release bursts of gonadotropin releasing hormone, (GRH) • Which stimulates the pituitary to secrete luteinizing hormone (LH) and follicle stimulating hormone (FSH). • These hormones stimulate the gonads to release estradiol or testosterone.

23. Estradiol & Testosterone • Elevated levels of estradiol causes breast development, growth of body hair, broadening of the hips, etc. • Elevated levels of testosterone causes lowering of the voice, hair and beard growth, muscle development, broadening of the shoulders, etc.

25. Female Reproductive Cycle • A strong example of the role of negative feedback (a self-regulatory process in which a system’s output fees back to the input part of the system, thereby reversing the direction of change of the output). • Last week, we talked about another example, the HPA axis negative feedback loop GRH -> ACTH -> Glucocorticoids -> GRH, etc.

26. Female Reproductive Cycle • Hypothalamus (GRH)  • Pituitary (FSH and LH)  • Gonads (ovaries) • FSH acts on the ovary to stimulate the growth of the follicle, which contains the egg or ovum. As the follicle grows it secretes estrogen.

27. Female Reproductive Cycle (cont.) • This estrogen feeds back to the pituitary, inhibiting it from sending out more FSH. • Estrogen also stimulates the pituitary to release LH, which causes the walls of the follicle to break, releasing the egg (ovulation). • After the release of the egg, the follicle tissue becomes the corpus luteum.

28. Female Reproductive Cycle (cont.) • LH causes the corpus luteum to secrete progesterone. • Progesterone increases blood supply to the uterus wall, preparing it for egg implantation. • Progestrone also feeds back to the pituitary, inhibiting the secretion of LH

29. Female Reproductive Cycle (cont.) • If fertilization does not occur, the corpus luteum shrinks, progesterone decreases, the uterine lining is gradually expelled in menstruation, and the cycle begins again.

31. H > P > G axis • Puberty • Sexual and Reproductive Behavior • Menopause

32. menopause

33. andropause

35. Rhythms • Daily rhythms affect your: • pulse rate and blood pressure, • blood sugar level, • body temperature, • gland secretions, • salt secretion by the kidneys • cell growth, etc. • These biological changes are called circadian rhythms, changes that occur daily.

36. Rhythms • The hypothalamus is the “control center” for coordinating bodily processes with the outside world. • In the front part of the hypothalamus is a specialized group of nerve cells called the suprachiasmatic nuclei (or SCN).

37. Rhythms • Linked by a track to the retina of the eye, which picks up light and dark signals from the environment. This system influences hormone secretion, particularly from the pineal gland. • The pineal gland secretes melatonin, which is typically secreted between 11 pm and 7 am and suppressed during the day.

38. Rhythms

39. Zeitgebers • External cues or “time-givers” are known as zeitgebers. • Examples include cycles of light and dark, watches and clocks, mealtimes and social routines, bedtimes, etc. • Sunday, November 03

40. Zeitgebers • The power of zeitgebers to affect how we feel can be seen in the phenomenon of jet lag and in our responses to shift-work.

41. Introduction to Biopsychology[PSB 4002] Professor Robert Lickliter DM 294 / 305-348-3441 licklite@fiu.edu website: dpblab.fiu.edu

42. Midterm #3 • Thursday, November 21 • Chapters 11, 17,19, & 20 in the textbook • Lecture material through November 19 • Sample study questions and powerpoint slides posted at dpblab.fiu.eduby Friday

43. Sleep and Waking

44. What is sleep? • An active process • Characterized by: • an increased threshold for stimulus detection • limited behavior • particular neuronal activity patterns

45. Who sleeps? • most animal species • all mammals

46. Why do we sleep? • We will spend approximately one-third of our lives sleeping and yet we still are not completely clear why we sleep and why we need so much sleep. • Three main theories: • homeostasis • inactivity/safety • neural plasticity/ memory formation/neural repair • Likely more than one theory is correct

47. Sleep • Sleep is an active process of the nervous system, involving systems in the: • brain stem, which contains the: • the reticular activating system, • the raphe nuclei (secretes serotonin) , • the locus coeruleus(secretes norepinephrine) • and of course, the rest of the CNS as well.

48. Brain Waves During Wakefulness • Alert: beta activity • Low amplitude • High frequency • Drowsy: alpha activity • Increased amplitude • Decreased frequency

49. Stages of Sleep • Not one state, but a dynamic, orderly, rhythmic succession of states, each with its own unique properties: • Stage 1: daydreaming, reveries (1-10 min or so) • Stage 2: sound sleep (40-60% of total sleep time)  • Stage 3: deep sleep (5-10% of sleep time) • Stage 4: deepest sleep (15-30% of sleep time) • REM sleep: every 90 min or so, 4-5 times a night

50. Stages of Sleep • NREM • Stage 1 • Stage 2 • Stage 3 • Stage 4 • REM