Chapters 17-18 Flashcards
What is the endocrine gland that’s considered the “master gland” and secretes hormones that regulate many of our bodily functions?
Pituitary gland
List the 6 things secreted by the anterior pituitary
1) ACTH
2) PRL (prolactin)
3) GH (growth hormone)
4) TSH
5) LH (luteinizing hormone)
6) FSH
List the 2 things secreted by the posterior pituitary
1) Oxytocin
2) Vasopressin
1) Where is the hypothalamus? What does it form?
2) What does it contain?
1) Underneath the thalamus; forms the walls and floor of the inferior portion of the third ventricle
2) Dozens of nuclei
1) What surface of the brain is the hypothalamus on?
2) Where is it in relation to the optic chiasm?
1) Ventral surface
2) Posterior to the optic chiasm
What part of the hypothalamus is the master clock of circadian rhythms?
Suprachiasmatic nucleus
What 2 things link the neural and endocrine systems?
Hypothalamus and pituitary
The hypothalamus the central regulator of what? How does it interact?
1) Homeostasis
2) Exerting influence over 4 other body systems:
-1-homeostatic mechanisms (that control hunger, thirst, sexual desire and sleep-wake cycles)
-2-endocrine control via the pituitary (controls release of hormones from the pituitary)
-3-autonomic control
-4-limbic mechanisms
List and describe the 4 systems the hypothalamus controls to maintain homeostasis
1) Homeostatic mechanisms: that control hunger, thirst, sexual desire and sleep-wake cycles
2) Endocrine control via the pituitary: controls release of hormones from the pituitary
3) Autonomic control
4) Limbic mechanisms
What two places does the hypothalamus receive inputs from?
The amygdala and regions of the limbic cortex
The limbic-hypothalamic interconnections play an important role in what?
Give an example
Emotional influences on autonomic pathways
-ex/ why your palms get sweaty and your stomach churns when you are anxious.
The regulator of circadian rhythms receives inputs from where? What do these contain?
Retinal ganglion cells containing photopigment melanopsin that contain information about day and night cycles.
What can the photopigment melanopsin communicate to the suprachiasmatic nucleus
Information about day and night cycles.
Lesions in the part of the hypothalamus that controls appetite can cause what?
Weight loss/obesity
1) What core survival function is partially regulated in the hypothalamus?
2) What can lesions in this part of the hypothalamus do?
1) Thirst
2) Decrease water intake
1) Oxytocin is produced in the hypothalamus and then released from the ____ pituitary
2) What does it do?
1) posterior
2) Increase nurturing behaviors
1) The limbic system contains a variety of structures from the ______________ to the _______________.
2) Where are most limbic system structures? Are the visible from the lateral view?
1) forebrain to the brainstem.
2) Most are hidden in the medial hemispheres and not visible from the lateral view.
The limbic cortex forms what? What two things does it surround?
A ring–like limbic lobe surrounding the corpus collosum and upper brainstem
1) What do the limbic cortices share?
2) Give an example
1) Certain surface immunological markers
2) Ex/HSV has a propensity for the limbic cortex and can cause severe encephalitis involving predominantly the limbic cortex
1) Structures of the limbic system regulate what 5 processes?
2) The limbic system contains what?
1) Emotions, olfaction, memory, drives and homeostasis.
2) Cortical and subcortical structures located mainly in the medial and central hemispheres
What are the 4 main categories of limbic system functions?
1) Homeostatic functions including autonomic and neuroendocrine control
2) Olfaction
3) Memory
4) Emotions and drives
HOME
What is the hippocampus’s:
1) Shape?
2) Location?
3) Function?
C-shaped structure buried in the medial temporal lobe important in memory functions
1) What is the amygdala?
2) Where is it?
3) What does it function in?
1) Complex of nuclei in the anteromedial temporal lobe
2) Tip of the hippocampus
3) Emotional, autonomic, and neuroendocrine circuits of the limbic system
Smell contributes to the detection of what two things?
1) Odors in the world
2) Taste (retro nasal smell)
Describe the path of olfactory receptor neurons (3 steps)
Send axons through the cribriform plate to the olfactory bulbs to the olfactory nerves > olfactory tract > olfactory cortex
Some fibers of the olfactory tract go where? Why?
Give an example of this function
Amygdala; some odors illicit old memories
**peppermint=> aids in memory and concentration
What are the two jobs of the hippocampus?
1) Memory
2) Creates context for past/future events
What are the 2 main regions in the brain that are critical for memory formations? What does each contain?
1) Medial temporal lobe memory area: contains the hippocampus
2) Forebrain: contains nuclei of the thalamus and hypothalamus.
-There are numerous pathways that connect the 2.
Today, patients with refractory temporal lobe epilepsy can be cured with what? Why?
Unilateral medial temporal lobe resection; to preserve memory by preserving one side
What are the two types of memory?
Declarative and nondeclarative
****
1) Define declarative memory
2) Define nondeclarative memory
***
1) Explicit memory; involves conscious recall of facts or experiences.
2) Implicit memory which involves nonconscious learning of habits, skills or other acquired behaviors.
John Doe could not recall new facts but, could learn things subconsciously. Therefore, he had lost his _________________ memory, but his _________________ memory stayed intact
declarative; nondeclarative
***
List the jobs of the pituitary hormones
Oxytocin: uterine contractions, milk letdown
PRL: milk production
FSH, LH: gonads
ACTH: adrenal cortex
TSH: thyroid (to make T3 and T4)
ADH (vasopressin): kidney water retention
GH: long bone growth
What does the posterior pituitary contain?
Axons whose cell bodies are located in the hypothalamus
1) What can the hypothalamus detect?
2) What can lesions there cause because of this?
3) What does the posterior hypothalamus do?
1) Increased body temperature
2) Hyperthermia
3) Conserves heat.
What are the 3 types of memory loss?
1) Anatomical abnormalities visible on imaging
2) No anatomical abnormalities visible on imaging
3) Normal forms of memory loss
Cerebral contusion caused by head trauma can result in what? What does it usually involve?
Permanent memory loss; usually involves the medial temporal lobes.
What is memory loss like in concussion?
Usually reversible memory loss except for a few hours around the injury
Can infarcts/ischemia cause memory loss? When?
They can, especially when bilateral medial temporal lobes are affected.
1) What cause of memory loss could be due to a cardiac arrest?
2) Is memory loss permanent? What structure is involved?
1) Global cerebral anoxia
2) Memory loss is usually permanent; the hippocampus is very vulnerable to anoxic injury
Seizures can cause what?
Memory loss
List 4 causes of memory loss
1) Concussion
2) Infarcts/ischemia
3) Global cerebral anoxia
4) Seizures
1) What is the amygdala? Where is it?
2) What two things does it play a big role in?
1) A group of nuclei in the anteromedial temporal lobe at the tip of the hippocampus
2) In emotions and drives.
1) The amygdala has direct and indirect connections to what 3 areas?
2) Where else does it have connections to? What is each related to?
1) Diverse cortical areas, the forebrain, and thalamus.
2) -Olfaction and the hypothalamus: related to appetite states.
-Hypothalamus and brainstem: involved in autonomic control and the control of breathing.
What is an active participant in all 4 limbic functions?
Amygdala
What is the amygdala important in?
Attaching emotions to stimuli perceived by the association cortex.
1) What emotional states is the amygdala involved in?
2) What 2 structures have reciprocal interactions with the amygdala?
3) What do all 3 structures do together?
1) Fear, anxiety, aggression, pleasure, and rage
2) Amygdala, hypothalamus and brainstem
3) Mediate changes in heart rate, peristalsis, gastric secretions, piloerections, and sweating
What two things cause anxiety?
1) Excessive activity in the amygdala
2) Failure of control by the frontal cortex
What NTs can be markedly imbalanced in bipolar depression/ mania?
Serotonin, norepinephrine, and dopamine
1) What structures being abnormal can cause schizophrenia?
2) What NT is can cause it, and what can improve symptoms?
1) Limbic system, frontal lobes, and thalamus.
2) An abnormality in dopamine, therefore symptoms can improve with antidopaminergic agents
