The organism that causes syphilis is

What is associated with the destruction of neurons that release a neurotransmitter called acetylcholine?

a. vascular depression b. amnesia c. vascular dementia d. Alzheimer's disease

A psychologist first conducted a study on helping behavior with a sample of college undergraduates. This psychologist then replicated the study using the same procedure with a different participant sample

If similar results were obtained with both samples, this experimenter has demonstrated a. internal validity. b. external validity. c. population consistency. d. chronological consistency.