Psychology 2135A/B Lecture Notes - 6 Years, Hermann Ebbinghaus, Diminishing Returns
Document Summary
Memory is to guide behaviour; do what worked last time. When born, lots of neurons, but a lot die off as relations between some neurons are built; some brain cells can be made but very insignificant amount. 100 billion to 500 billion neurons; each neuron on average makes 10000 connections. Connections appear to allow storage of information. Neurons have random rate of firing and rate can increase or decrease due to presentation of stimulus; increases capacity of memory. Tested older people on their recall off spanish vocabulary learned in high school many years earlier; 50 years later, a lot of it survived; not used or rehearsed. General trend: recall declined for first 3 to 6 years; not much forgetting for the next three decades; final decline after 30 to 35 years. Herman ebbinghaus (1850-1909); first scientific studies of memory; interested in forgetting; used himself as a subject (1885)