Psychology 1000 chapter 1 notes. Luigi galvani performed an experiment with frog leg and electricity and discovered that brain signals were electrical in nature. Karl lashley created lesions in specific parts of the brain to study its effect on memory and learning. James olds and peter milner of mcgill university discovered that certain areas of the brain gave animals pleasurable sensations. Eeg (1929) allowed researchers to measure brain activity in certain areas of the brain. Biochemical research shows that the brain(cid:110)s electrical activity is controlled by chemicals released by nerve cells o. Evolution and behaviour: from darwin to evolution psychology. Humans exist because of our ancestor(cid:110)s ability to adapt to a changing, hostile environment. Darwin proposed that species evolve over time as a response to environmental conditions in a process called natural selection. Any inheritable characteristic that enhances survival will be maintained.