Behavioral Neuroscience: Hormones, Homeostasis, Sleep, and Emotion

Practice flashcards covering endocrinology, sexual differentiation, fluid homeostasis, feeding circuitry, biological rhythms, sleep mechanisms, and neural circuits of emotion.

Which hormone is also called antidiuretic hormone (ADH)?

Vasopressin

Which gland releases oxytocin and vasopressin into the bloodstream?

Posterior pituitary

How is neural signaling typically characterized compared to hormonal signaling?

Precise and fast

How do peptide hormones primarily exert their effects on target cells?

Activating second messenger systems

What is the primary mechanism of action for steroid hormones?

Acting as transcription factors after binding intracellular receptors

Which hormone causes mammary gland contraction during milk let-down?

Oxytocin

What is the definition of a tropic hormone?

A hormone that acts on another endocrine gland

A goiter resulting from iodine deficiency develops largely because of excessive levels of which hormone?

TSH (Thyroid-stimulating hormone)

What does congenital hypothyroidism refer to?

Inadequate thyroid hormone in newborns

Which hypothalamic hormone stimulates the release of FSH and LH?

GnRH (Gonadotropin-releasing hormone)

In males, what does luteinizing hormone (LH) mainly stimulate?

Testosterone secretion

In females, what does luteinizing hormone (LH) trigger?

Ovulation and corpus luteum formation

How do oral contraceptives primarily prevent ovulation?

Negative feedback on hypothalamic GnRH release

On which chromosome is the SRY gene located?

Y chromosome

Without a functional SRY gene, toward what does development generally proceed?

Ovarian formation

What defines an organizational effect of hormones?

Permanent developmental structuring of brain/body

Which enzyme converts testosterone into dihydrotestosterone (DHT)?

5\textbackslash alpha\textbackslash text{-reductase}

Which condition is characterized by a fetus having testes and producing testosterone, but cells being unable to respond because receptors are defective?

Androgen Insensitivity Syndrome (AIS)

What condition describes a child raised as female who develops a penis during puberty because elevated testosterone can act on tissues despite a developmental deficiency in DHT synthesis?

Guevedoces

What is the primary developmental effect of Anti-Müllerian Hormone (AMH)?

Regression of Müllerian ducts

Which brain region is strongly implicated in sexual performance in both sexes?

mPOA (medial preoptic area)

Which neurotransmitter contributes to the male refractory period?

Serotonin

How does the sexually dimorphic nucleus (SDN/INAH3) in human men compare in size to that in women?

Approximately 2-3\textbackslash times larger in men

What size SDN-POA do female rats develop when exposed to testosterone during puberty?

Female-sized SDN-POA

What is the correct sequence of the endocrine cascade for sex steroid production?

GnRH → LH/FSH → Gonads → Sex Steroids

What function is abolished in rats by lesions of the lateral hypothalamus?

Behavioral regulation of temperature

Which situation most strongly stimulates osmotic thirst?

Excess salt consumption

What physiological change triggers hypovolemic thirst?

Reduced extracellular/intravascular volume

Which receptors initially detect hypovolemic thirst?

Baroreceptors

What is a major physiological effect of angiotensin II in thirst signaling?

Stimulate the subfornical organ

Where are osmosensory neurons that detect increases in osmotic pressure located?

OVLT (organum vasculosum of the lamina terminalis)

Defects in leptin production or receptor sensitivity provide the brain with a falsely low report of what?

Body fat reserves

According to the lecture, what leptin status describes most obese individuals?

Leptin-resistant

What is ghrelin and where is it primarily released from?

An appetite stimulant from stomach endocrine cells

What hormonal alteration is associated with Prader-Willi syndrome?

Elevated ghrelin levels

Lesions to which hypothalamic area classically lead to obesity?

Ventromedial hypothalamus (VMH)

Destruction of the lateral hypothalamus most likely causes which behavior?

Refusal to eat

What are the primary metabolic effects of NPY/AgRP neurons?

Stimulate appetite and lower metabolism

What primary effects are promoted by POMC/CART neurons?

Appetite inhibition and increased metabolism

How does leptin act on hypothalamic circuitry?

Inhibiting NPY neurons while stimulating POMC neurons

What is a major physiological reason why fad diets often fail?

BMR falls, opposing weight loss

Why does leptin therapy usually fail as a treatment for obesity?

Most obese individuals are leptin resistant rather than leptin deficient

If stranded at sea, which pathway is activated first when a student drinks seawater?

OVLT osmosensory neurons responding to increased osmotic pressure

How is a biological rhythm that occurs several times per day classified?

Ultradian

What term refers to external cues that synchronize the circadian clock?

Zeitgebers

Through which anatomical pathway does light information reach the body's master clock?

Retinohypothalamic pathway

Where is the body's master circadian clock located?

Suprachiasmatic nucleus (SCN)

What biological function is specifically abolished by lesions of the suprachiasmatic nucleus (SCN)?

Circadian rhythms specifically

What shift in circadian timing do most individuals experience at puberty?

Later circadian timing

During morning daylight, what does increasing light promote the release of?

Cortisol, serotonin, and adrenaline

Which biochemical conversion by the pineal gland produces Dim Light Melatonin Onset (DLMO)?

Converting serotonin into melatonin

What electrophysiological and physiological features characterize REM sleep?

Fast EEG activity and rapid eye movements

Early in the night, sleep cycles contain proportionally more of which type of sleep?

Stage 3/4 slow-wave sleep

During which sleep stages do dreams occur?

Both REM and non-REM sleep

During which sleep state do vivid dreams with strong visual imagery most commonly occur?

REM sleep

From which sleep state do night terrors typically arise?

Stage 3/4 slow-wave sleep

What unique sleep pattern occurs in dolphins and some birds?

One hemisphere enters SWS while the other remains awake

How does infant sleep differ from adult sleep?

More REM sleep and shorter sleep cycles

Which hypothalamic region coordinates sleep onset?

VLPO (ventrolateral preoptic nucleus)

Which neural structure is most responsible for wakefulness?

RAS (reticular activating system)

Why does sensory information reach the cortex less effectively when falling asleep?

The thalamus becomes less sensitive to environmental input

What is the diagnosis for a patient who suddenly enters REM sleep directly from wakefulness and experiences cataplexy?

Narcolepsy

What is the normal function of orexin in sleep regulation?

Stabilize the sleep-wake switch

Which sleep disorder involves incomplete or absent REM paralysis?

REM sleep behavior disorder

What disorder is characterized by loud snoring, repeated cessation of breathing during sleep, and daytime sleepiness?

Sleep apnea

Which treatment is specifically mentioned for sleep apnea?

CPAP

What can continued use of Ambien lead to?

Receptor downregulation and memory gaps

What is the primary function of the orbitofrontal cortex in emotional regulation?

The controller that inhibits raw emotion

Which neurotransmitter released by the locus coeruleus is strongly associated with emotional arousal and stress?

Norepinephrine

Which structure was most likely damaged in a patient who becomes unusually trusting and shows little fear?

Amygdala

Which limbic structure is especially important for empathy and pain processing?

Cingulate gyrus

Which statement supports the facial feedback hypothesis?

Smiling can increase positive emotional experience

According to the lecture, why may Botox treatment reduce negative mood?

It limits frowning

Which brain region is activated by both physical disgust and moral disgust?

Insula

Why is the 'low road' of emotion biologically important?

Allows rapid responses before full cortical processing

What behavioral symptom is expected in a monkey with Klüver-Bucy syndrome?

Reduced fear and anxiety

Which cerebral hemisphere is generally more active during fear and sadness?

Right hemisphere

What emotional state is often caused by damage to the left hemisphere?

Greater anxiety and sadness

What emotional function is the right hemisphere particularly important for recognizing?

Emotional tone of voice

Which brain structure is considered the final destination for emotional information before an action is taken?

Prefrontal cortex

Which pair of hormones is released from the adrenal medulla?

Epinephrine and norepinephrine

Why can acute stress be beneficial?

Increases neurogenesis and temporarily boosts immunity

Why does vagus nerve stimulation help individuals with PTSD?

It activates the parasympathetic nervous system

Which type of aggression is premeditated and emotionless?

Proactive aggression