Week 1 Flashcards
1
Q
What is the “journal impact factor”?
A
An estimate of how many times you will be cited yearly after being published in a particular journal.
2
Q
What is the “h-index”?
A
A RATIO of how many publications to how many times you’ve been cited.
3
Q
What are the most difficult things to evaluate in the peer-review process?
A
Novelty & impact
4
Q
What is the most critical part of peer review?
A
Evaluating the soundness of the science.
5
Q
What is a problem with the peer review process and what does this problem lead to?
A
Personality and politics coming into play
- Politics might lead publications to be rejected unfairly
- Friendship leads to lower-quality papers being approved
6
Q
What is the advantage of PLoS ONE and other open access journals?
A
People can comment on the impact a publication has had even years later.
7
Q
What is the basic assumption of the Scientific Approach?
A
That events are governed by some lawful order (and that lawful order is what is generally being researched).
8
Q
What was the problem with facilitated communication, and how did they finally disprove its efficacy?
A
The facilitators were biasing the responses, and the best way they finally disproved the usefulness was by using a machine as a facilitator (to remove all potential human bias).
9
Q
What is the most critical factor in making research “scientific”?
A
Relying on EMPIRICAL evidence gathered thru the scientific method.
10
Q
What is the name for “an organized system of assumptions that aims to explain phenomena and their interrelationships”?
A
A theory.
11
Q
What is the name for “an attempt to predict or account for a set of phenomena, specific relationships among variables, and are empirically tested”?
A
A hypothesis.
12
Q
What is required in an “operational definition”?
A
A definition of the term that specifies the operations for observing AND measuring the term in question.
13
Q
What was the very important principle that Karl Popper established as a requirement for scientific theories?
A
The “Principle of Falsifiability”:
- Theories must make predictions that are specific enough that they CAN be disproved.
- Theories must predict what WILL happen, and what will NOT happen.
14
Q
In scientific research, what is reliability? What is Validity? and which is a requirement for the other?
A
Reliability refers to the CONSISTENCY of a measurement.
Validity refers to the fact that the measure truly measures what it is supposed to.
Reliability is needed before validity, because first you need to make sure your measure repeatedly assesses the same thing –> THEN you need to make sure the thing being repeatedly measured is the RIGHT thing.
15
Q
What exactly is the “correlation coefficient”?
A
A measure of how strongly two variables are related to one another - goes from -1 to 1.
16
Q
What exactly is the “correlation of determination”?
A
An index of the predictive power of the correlation. A simple measure of “effect size”. It’s the square of the correlation coefficient.
17
Q
What is the biggest pitfall of experimental studies?
A
There can be confounding variables that interfere with making valid conclusions from results.
18
Q
What is “hindsight bias”?
A
The feeling that “I knew it all along!”
19
Q
What is a way of preventing the placebo/nocebo effect aside from blinding?
A
Using a “switched-over” design where subjects receive the control AND experimental condition at different timepoints.
20
Q
What is the “Hawthorne Effect”?
A
When subjects’ knowledge that they’re being studied affects their behavior.
21
Q
If your sample isn’t representative of the population, is the validity of your study completely ruined?
A
Not completely - You can’t generalize with much certainty, but if the effect size is very large then it is a good indication that something is going on.
22
Q
In a normal distribution, how far from the mean do most scores fall?
A
68% of scores will fall within plus or minus 1 standard deviation.
23
Q
What do inferential statistics allow us to do?
A
Determine whether we can generalize from the study sample to the population.
24
Q
What does “statistical significance” refer to?
A
The probability that the finding has occurred by chance (ex. p<0.05 means that the finding would occur by chance less than 5% of the time).
25
What is an "alpha error"?
A finding from the sample NOT being generalizable to the population (finding something that's not real).
26
What is a "beta error"?
Missing something in the sample that IS present in the population.
27
What does the T-test evaluate?
Whether the difference between two means is statistically significant.
28
Think of a dog standing on its four legs:
1. How do you refer to something towards the dog's nose?
2. How do you refer to something towards its tail?
3. How do you refer to something towards its back?
4. How do you refer to something towards its tummy?
1. Rostral/anterior ("in front")
2. Caudal/posterior (the furthest from the head)
3. Dorsal/superior
4. Ventral/inferior
29
What are the 3 protective layers of the CNS and why is so much protection needed?
Because the CNS is all-important and needs to be protected against infection and toxicities.
30
What structures are in the hindbrain?
- Cerebellum
- Pons
- Medulla
- Reticular formation
31
Where are the tectum and tegmentum located?
The midbrain.
32
What are two dopamine-related structures located in the midbrain?
Periaqueductal gray and substantia nigra
33
Where is the diencephalon located and what structures does it contain?
The diencephalon is in the forebrain and contains the thalamus and hypothalamus.
34
Where are the basal ganglia, limbic system, and cerebral cortex located specifically and generally?
In the telencephalon of the forebrain.
35
What structures are referred to as the basal ganglia, and what neurotransmitter seems to be important to them?
- Caudate nucleus
- Putamen
- Globus Pallidus
DOPAMINE.
36
What are some VIP structures of the limbic system?
- Hypothalamus
- Hippocampus
- Amygdala
37
What seem to be the main tasks of the limbic system?
Emotion, learning, and memory. Could say that "learning is embedded in memory, and emotion helps".
38
What has called into question the traditional idea that activation of the SNS and the parasympathetic NS are mutually exclusive?
Activation of BOTH during things that are very pleasurable or mild intensity exercise.
39
How many times more glial cells are there than neurons?
10-50x more.
40
These structures are all located in the ________ :
- Nucleus
- Nucleoleus
- Smooth ER
- Rough ER
- Mitochondria
- Microtubules
- Golgi apparatus
- Ribosomes
Cell BODY of neural cells (AKA the soma).
41
Bipolar neurons seem to be located in places with a specific function - what do these functions have in common?
They are part of sensory systems.
42
Do afferent or efferent neurons take information TO the CNS?
Afferent.
43
What is an interesting function that astrocytes accomplish, aside from provide energy to neurons?
They uptake excess neurotransmitters from synaptic clefts, store it, and can re-release it later to be taken care of (for example during dreaming!)
44
Are there more chemical or electrical synapses in the brain?
Chemical.
45
What are some advantages of chemical SYNAPSES (neurotransmitters) over electrical?
- Chemical effects are generalizable, can be wide-spread on multiple neurons rather than just from a single neuron to a single other neuron.
46
Which are the two most common neurotransmitters in the brain and each are exclusively excitatory OR inhibitory?
Glutamate and GABA.
47
How does tetanus work?
The tetanus toxin infiltrates the CNS thru retrograde transport in neurons. Then it binds to GABA receptors, blocking them. GABA can no longer bind to them and provide inhibition, so the cells fire too much causing muscle spasms.
48
What is the name of the most popular model of neuronal communication?
The "Neural Network" model.
49
What is the definition of a hormone? Try to include:
- What exactly it is
- Where it's created
- The way it has its effects
- A chemical messenger that's effective in minute quantities
- Synthesized generally in ductless glands, but can be in other places also (just need the proper enzyme)
- Usually transported in the blood to have regulatory effects on other bodily tissues
50
What does "paracrine" mean? "autocrine"?
Paracrine: Acts as a neurotransmitter, locally
Autocrine: Has effects on the cell that released it
51
What are the two general classes of hormones?
1. Amino acids & peptides
| 2. Steroid (stress and sex)
52
Why did scientists argue against the existence of hormones in the early period of endocrine discoveries?
Because everyone was just discovering and focusing on neurotransmitters and electrical neural communication.
53
Why did Harris think it was important to study hormones in the hypothalamus & pituitary?
Because this research allowed him to connect environmental stimuli to hormonal regulation through the nervous system.
54
What structure connects the hypothalamus to the pituitary?
The medial eminence
55
What are two advantages of hormone cascades (ex. HPA/HPG/HPT)
- They provide amplification of signals
| - They provide multiple levels of intervention
56
Where is CRH synthesized, and what hormone does it stimulate the release of?
- In the PVN of the hypothalamus
| - ACTH
57
Where is GnRH synthesized, and what hormone does it stimulate the release of?
- In the preoptic area of the hypothalamus
| - FSH & LH
58
Where is GHRH synthesized, and what hormone does it stimulate the release of?
- In the VMN & arcuate nucleus of the hypothalamus
| - GH
59
Where is TRH synthesized, and what hormone does it stimulate the release of?
- In the PVN of the hypothalamus
| - TSH
60
When Dopamine acts as a hormone in the brain, where is it synthesized and what does it do?
- In the arcuate nucleus of the hypothalamus
| - It inhibits the release of prolactin in the pituitary
61
What is another name for GH-IH, and what does it do?
Somatostatin, it has inhibitory effects on GH and TSH
62
Oxytocin and vasopressin are different from other hypothalamic hormones. How so?
They are synthesized in the hypothalamus and are transported by neurons directly for release in the posterior pituitary.
63
What is the cause of acromegaly?
Overproduction of GH by the pituitary after puberty.
64
What important concept in hormonal effects does the contrast between the effects of too much GH before puberty or after puberty exemplify?
Organizational vs. activational effects.
65
Think of what brain region the hypothalamus and pituitary are located in. Because of this, what general cognitive functions are hormones probably involved in?
Learning, memory, emotions (limbic system!)
66
Explain the way light relates to sleep-wake cycles (brain structures + hormone)
Light --> retina --> (melanopsin) -----> SCN --> SUPPRESION of melatonin production by Pineal gland.
67
Which thyroid hormone is there more of in circulation?
T4
68
Why does the thyroid gland get enlarged in goitre?
Because of the excess demand being put on it, there is hypertrophy of the tissue (think of hypertrophy when working out any muscles!)
69
What is the main effect of hyperthyroidism? Why does this make sense considering the role of the thyroid?
Accelerated aging. It makes sense because the thyroid is involved in regulating metabolism - if there is accelerated metabolism, tissues age faster!
70
What are some general symptoms of hypothyroidism - contrast the organizational vs. activational effects of this condition. What can we infer about the roles of T3 and T4?
Organizational: Severe mental retardation (T3 & T4 must have a role in neural development)
Activational: Increased fatigue, facial puffiness, skin problems (T3 & T4 important for physical and mental health)
71
Where are insulin and glucagon (among others) produced?
The islets of Langerhans.
72
Where is glycogen found?
In the cells of the liver and muscles.
73
How does insulin resistance develop?
Chronically elevated blood glucose (diet) leads to chronically elevated insulin. Chronically elevated insulin leads to down-regulation of insulin receptors --> the system is no longer as sensitive to the effects of insulin.
74
Name the hormones produced by the adrenal cortex vs. adrenal medulla. Link them to the stress systems.
Cortex: Cortisol, aldosterone, androgens, estrogens (HPA)
Medulla: Adrenaline, noradrenaline, dopamine, enkephalins (SNS)
75
Why does it make sense that adrenal hyperactivity is linked to obesity?
The effects of adrenal activity generally try to make more energy available to an organism - this includes storing as much energy as possible for future use!
76
What is the acrophase of a rhythm?
The time it takes from a selected reference point to the peak of the rhythm.
77
What is the acrometron of a rhythm?
The highest predicted VALUE of the variable.
78
Which type of rhythm occurs more frequently than once a day, infradian or ultradian?
Ultradian.
79
Explain the "hormone rhythms as a symphony" metaphor.
Cells are able to understand the superimposition of multiple hormone rhythms in a meaningful way just like we are able to perceive a cohesive symphony from multiple superimposed melodies.
80
At what time of day is GH at its highest? Why does this make sense?
During the night, it makes sense because during rest/sleep there is nothing to interfere with repair and growth and the organism can put lots of resources into these activities.
81
Dr. P says brain repair and body repair occur primarily during different sleep stages. Associate the stage to the type of repair.
REM: Brain repair
| Slow-wave: Body repair
82
Why is there proportionally (and literally) more REM sleep in young children, and why does it make sense that the amount of REM sleep stabilizes and then overall sleep time decreases through adulthood?
REM is associated with brain repair/development so it makes sense that very young infants whose brains are still developing need more of it.
As we know, neurogenesis doesn't really occur (much) in humans, so the amount of REM needed stabilizes.
Overall levels of sleep decrease in adulthood probably because of a vicious cycle of aged/damaged cells not being able to produce enough hormones to maintain sleep for long enough to do all the repair, therefore perpetuating damage and lack of hormones.
83
How does Dr. P prefer to explain dreams and their function/meaning?
Astrocytes that took up excess NT from synapses activated during the day re-release it into synapses during sleep. This means that the same synapses get reactivated during sleep - daily thoughts and problems can get addressed and solved.
84
Why do fully blind people (light-insensitive) have generally higher melatonin levels even though they seem to sync to a normal 24h cycle?
Because they don't get the light stimulation to inhibit melatonin production. Their 24h rhythm has nothing to do with light, it has to do with environmental stimuli.
85
What is easier on our circadian rhythm - travelling East or travelling West?
West. (easier to prolong a day than shorten a day)
86
What is the one predictable variable that influences seasonal/infradian rhythms?
Duration of day light.
87
What is the probable purpose of the cortisol awakening response (CAR)?
Giving a first energizing boost to get an individual's day started.
88
What life factors were overall significantly related to magnitude of the CAR?
Job stress and general life stress.
89
Depression was both positively and negatively correlated to CAR magnitude depending on the measures - what can we conclude?
It's an overall non-significant factor for CAR magnitude BUT there is clearly something going on that probably warrants further investigation (the effects of depression are not clearly understood).
90
Although fatigue, burnout, and exhaustion were not significantly correlated to CAR magnitude, what was the tendency?
Generally a negative correlation even though not significant.
91
What is the only part of PTSD that seems to be correlated to CAR magnitude? What was the direction of this correlation?
The strength/severity of the PTSD. Negative.
92
What are some differences between the nervous system and the endocrine system?
- Messages can be transmitted electrically in the nervous system.
- Neurotransmitters don't travel in the blood.
- Some hormones have effects on every cell they encounter, neurotransmitters don't.
- NS is more on/off, endocrine is more continuous
- NS is quicker than endocrine, but effects of endocrine last longer
93
What are some similarities between the nervous system and the endocrine system?
- Chemical messengers are used in both.
- Some hormones actually also function as neurotransmitters in the nervous system.
- Both types of chemical messengers can be stored for later release.
94
Describe mediated hormone action:
- How does it interact with target cell?
- What activity does it generate in the target cell?
- What type of hormones?
- It binds to receptors and induces second messenger activity
- It relates to cell metabolism AND gene expression
- Monoamine, polypeptide, and prostaglandins
95
Describe direct hormone action:
- How does it interact with target cell?
- What activity does it generate in the target cell?
- What type of hormones?
- It directly penetrates the cell, penetrates the cell nucleus
- Generates gene expression thru mRNA and therefore protein synthesis at ER
- Thyroid and steroid hormones --> THIS MAKES SENSE BECAUSE THEY'RE LIPID-BASED. EASY DIFFUSION INTO CELLS.
96
What class of hormones are the catecholamines, tryptophans, and tyrosins?
AMINE hormones
97
What class of hormones is mostly comprised of hypothalamic and pituitary hormones?
PEPTIDE hormones
98
What class of hormones is comprised of stress and sex hormones?
STEROID hormones
99
What is the main lipid hormone?
Prostaglandin
100
Of the 3 types of steroid hormones (glucorticoids, mineralocorticoids, and sex steroids), which ones are anabolic?
Sex steroids
101
How does non-steroid hormone synthesis generally work (building blocks and process)?
Amino acids are synthesized into preprohormones by the rough ER. The preprohormones are cleaved into prohormones by enzymes for stable, easy transport and storage in secretory vesicles, then before being released they are cleaved again into simple hormones. They are secreted through exocytosis.
102
How does steroid hormone synthesis generally work? (building blocks and process)?
Dietary cholesterol from the blood is taken up into gonad/adrenal cells. Mitochondria convert it to pregnenolone. Pregnenolone is converted to progesterone in the smooth ER. Progesterone can be secreted as-is as a hormone or be further modified by other enzymes to result in Aldosterone, Cortisol, or gonadal steroids
103
Do any hormones cross the blood-brain barrier? if so, which?
Sex and stress hormones (small, lipid-based)
104
Discuss the possible hormonal causes for gender differences in cognitive decline?
Estrogen is neuroprotective, which is why women's cognitive faculties stay better than men's into late middle-age. While men have already begun a gradual decline years ago, women's decline begins later but is sharper. Women's cognitive disability eventually surpasses males. This may be because men continue to have small amounts of estrogen thanks to their testosterone being converted by aromatase.
105
What is one emotional effect of progesterone that the general public might not be aware of?
It selectively increases amygdala activity in women. Can have anxiolytic effects.
106
Which type of adrenal hormone receptors in the brain are more sensitive to the presence of adrenal hormones? where do they tend to be located?
Type 1: Mineralocorticoid receptors, they are mostly in the limbic system (help with day to day learning, memory, and emotional behavior)
107
Why does it make sense that glucorticoid receptors are all over the brain?
Because they have a low affinity for adrenal hormones, they will only react in serious situations when the entire brain is flooded with adrenal hormones, and the entire brain needs to be on high alert BECAUSE something stressful is happening.
108
Which two endocrine glands (outside the CNS) have brain receptors that interact closely?
Adrenal glands and thyroid gland
109
What is an aspect of the "ablation" method that we often forget?
To establish a causal link, the hormone that was removed must be REPLACED, and the effects of removal are reversed.
110
What is an inherent problem with immunoassays?
The sheer numbers (of molecules) involved leads to error which we call "natural variance" or "intra-assay variability" and needs to be controlled for.
111
In radioimmunoassays, are antibodies involved? What is competing with what?
Yes, they can be. Untagged hormones (the one ACTUALLY being studied) compete against radioactively-tagged hormones (which can be directly measured) to bind to receptors.
112
What is a simple summary of the goal of autoradiography?
It's used to determine the location of hormone receptors and uptake in a tissue. Hormones are radioactively labeled, and poured on a tissue to see where they bind.
113
Which brain imaging technique (that gives a real image) is the only one that can be considered FUNCTIONAL?
fMRI.
114
What is the basic assumption about people and their gender?
That there is a deep inner conviction that one belongs to the gender of the sex they possess.
115
We know that gonads are undifferentiated until 6 weeks of gestation. By how many weeks have the Mullerian ducts disappeared if they're going to? Then by how many weeks have the Wolffian ducts developped into spermatic ducts?
10 weeks. 12 weeks.
116
Do the testes descend into the scrotum before or after birth?
Before.
117
By how many weeks have the Wolffian ducts disappeared if they're going to? By how many weeks have the Mullerian ducts developed into uterus and fallopian tubes?
10 weeks. 20 weeks. (takes longer for females to develop full uterus and fallopian tubes than males to develop spermatic ducts)
118
A surge in hormones from which gland is seen at puberty?
The hypothalamus. Kind of trick question; the surge is majorly in GnRH, which obviously then leads to a surge in LH and FSH and then the respective sex hormones.
119
What happens in Tanner stage 1, for both boys and girls?
No visible changes. A slight pre-pubertal adrenal gland increase in androgens.
120
In Tanner stage 2, what happens for both boys and girls, and then what is different?
Surge in GnRH -> FSH, LH. In both, the gonads enlarge and begin to produce sex hormones. In both, pubic hair begins to appear.
In GIRLS: Breasts begin to grow (breast buds), height and weight start changing, external genitals and uterus also enlarge.
121
In Tanner stage 3, what happens to boys and what happens to girls?
BOYS: Gonads continue to enlarge. Penis lengthens. Growth spurt, voice change. Maybe gynecomastia.
GIRLS: Breast development expands. Internal & external reproductive organs continue to enlarge.
122
In what Tanner stage do girls start menstruating and boys start ejaculating?
Stage 4.
123
In Tanner stage 5, are there any significant events for boys or girls?
No. They're pretty much reached adult size and resemblance.
124
Where does aromatase convert testosterone to estradiol?
In the brain, close to estrogen receptors.
125
Babies can distinguish between the sexes at ______ months. Children learn their own gender and know that it's stable around ____ yrs old.
9 mths.
| 3-4 yrs.
126
Can individuals with Klinefelter syndrome reproduce?
No, they produce little to no sperm.
