Lecture 3: The Brain

Question 1

Ethics in Research
Informed consent =
Attrition =
Protection of participants =
Confidentiality =
Debriefing = ____
Deception controls for ____ and ____.

Answer 1

Informed consent = Subject is given all information relevant to participation, including the possibility of harm (e.g. reactions to drugs)

Attrition = Freedom to leave at any point

Protection of participants = No unnecessary harm or distress

Confidentiality = Participant’s data is kept anonymous

Debriefing = Hypotheses + procedure explained, any deception revealed

(deception controls for placebo effect and demand characteristics)

Question 2

Statistical analysis
Testing Hypotheses
Null hypothesis (Ho) = ____
Alternate hypothesis (Ha) = ____
If we reject the null and accept the alternative, we say there is a ____

Answer 2

Testing Hypotheses

Null hypothesis (Ho) = no difference between groups

Alternate hypothesis (Ha) = there is a difference

If we reject the null and accept the alternative, we say there is a treatment effect/effect.

Question 3

Statistical analysis
Statistical test
= ____
p value = ____
p threshold = ____ (determined ____)
p-hacking = ____
- ____
- ____

Answer 3

= Measure of the statistical significance of the effect

p value = the probability a result is due to chance

e.g. If p = 0.05, there is only a 5% probability could be due
to chance

p threshold = the cut-off p value test p value is compared to to decide whether a result is statistically significant (determined in advance)

p-hacking = intentionally or unintentionally manipulate their data or analysis to get a statistically significant p-value

• Reorganizing their study (e.g. removing groups)
• Repeatedly running tests (high error risk)

Question 4

Statistical analysis
Effect Size Test
= ____
(statistically significant vs effect size)
____

Answer 4

Effect Size Test

= Statistical measure of the magnitude of an effect (from strong to weak)

• Some effects are statistically significant and strong; Other effects are statistically significant but weak.

Question 5

Statistical analysis
Sample size
____ sample size = ____ reliability
Strong effects can be detected with ____ samples
Weak effects need ____ samples
(even though strong effects can show up in small samples, researchers still aim for____)

Answer 5

Sample size

Large sample size = high reliability

Strong effects can be detected with small samples (e.g., n ≈ 10)

Weak effects need much larger samples (e.g., n ≈ 50, 100, 500)

(even though strong effects can show up in small samples, researchers still aim for large sample sizes)

Question 6

Statistical analysis
Replication
= ____
The replication crisis
Causes: ____, ____, ____
Solution: ____.

Answer 6

Replication

= repeating a study using the same methods to see if you get the same results

The replication crisis

Causes: P-hacking; Small sample sizes; Publication bias

Solution: Pre-registration and open science

Question 7

Neurons and the Nervous System
The Nervous System = ____ + ____
Neuron Parts and Function
Dendrites —
Cell body —
Axon —
Myelin —
Axon terminals —

Neurotransmitters
There are ____ transmitters; ____ receptors for each transmitter; ____ functions for each receptor (____ vs. ____)
Agonist = ____
Antagonist = ____
Competitive antagonist = ____
- Can be used to ____

Answer 7

The Nervous System = Central (CNS) and Peripheral (PNS)

Neuron Parts and Function

Dendrites — Input signal (receives transmitter)

Cell body — Signal integration **(decides whether to fire an action potential or not)

Axon — Signal transmission (Action potential)

Myelin — Insulates the axon to speed up signal transmission

Axon terminals — Output signal (release of transmitter)

Transmitter released by Neuron A travels across the synapse to affect receptors on Neuron B

Neurotransmitters

There are many transmitters; many receptors for each transmitter; many functions for each receptor (inhibitory vs. excitatory)

Agonist = a compound that binds to a receptor and produces a response

Antagonist = a compound that binds to a receptor but does not produce a response

Competitive antagonist = competes with the agonist for the ligand-binding site

• Can be used to block the effects of agonist and stop overdoses