Biological Rhythms, The Tides of Experience

Question 1

Define: Biological Rhythm

Answer 1

• regular, periodic fluctuations in a biological system

- may or may not have psychological implications

Question 2

What types of cues do biological rhythms follow?

Answer 2

• external time cues

- endogenous cues (internal)

Question 3

Define: Circadian Rhythm

Answer 3

• biological rhythms that occur approximately every 24 hours

- they affect physiology and performance

Question 4

What have researchers found when identifying engodenous cues completely removed from external cues?

Answer 4

-most people still settle into a day that is about 24 hours

Question 5

What controls circadian rhythms?

Answer 5

• suprachiasmatic nucleus (SCN)

- located in the hypothalamus

Question 6

Function: suprachiasmatic nucleus (SCN)

Answer 6

• responds to light and dark changes, then sends messages to the brain and body to adapt
• regulates changing levels of hormones and neurotransmitters, which in turn, provides feedback that affects how the SCN functions

Question 7

How does the SCN regulate sleep?

Answer 7

• Melatonin, which is secreted by the Pineal Gland, is regulated by the SCN
• Melatonin levels rise in the night, and fall in the morning

Question 8

Define: Internal Desynchronization

Answer 8

-when biological rhythms are out of phase

Question 9

Why has there not been a simple cure discovered for internal desynchronization?

Answer 9

• because circadian rhythms are not perfectly regular in daily life
• they differ greatly due to environment and genetics

Question 10

Define: Seasonal Affective Disorder (SAD)

Answer 10

-when a person experiences depression in the winter seasons, where there is less daylight, and experiences mood improvement in the spring

Question 11

What is said to help mild-moderate SAD, as well as non-seasonal depression?

Answer 11

-light therapy

Question 12

Explain: Menstrual Cycle

Answer 12

1st half of cycle
-increase in estrogen thickens uterine lining

mid-cycle
-ovaries release ovum

afterward

• ovarian sac produces progesterone, preparing uterine lining to receive egg
• without conception, estrogen and progesterone levels fall, and uterine lining slides off as the menstrual flow

-cycle repeats

Question 13

Define: “PMS” Premenstrual Syndrome, and Premenstrual Dysphoric Disorder “PMDD”

Answer 13

• PMS, emotional and physical symptoms associated pre-menstrual cycle
• PMDD, more debilitating version of PMS

Question 14

Why is PMS and PMDD more rare than the public leads us to believe?

Answer 14

• fewer than 5% of all women have such predictable symptoms over their cycles
• there are many biases, people may overlook normalcy and only attribute feelings to PMS
• women’s moods actually fluctuate LESS over menstrual cycle than any other days of the week
• empirical research FAILED to establish connection between menstrual cycle phases and effects on real-life matters