The anticholinergic plant with a forked root that is mentioned in the Bible is

Why have scientists recently begun to realize that some of their long-held beliefs about the aging brain were false?

People are living longer. Older people have become more aware of their own brain functioning. Noninvasive imaging techniques that can be done on live brains have become available. More laboratory analyses of brains of deceased Alzheimer's patients have been conducted.

Much of the history of psychology has been characterized by

a. the belief that ideas matter greatly. b. general agreement about the subject matter of psychology. c. uncertainty with respect to the definition of psychology. d. considerable agreement among researchers as to appropriate methodologies.