Chapter 2 – Physiology, psychophysics and the science of mind

Question 1

10) Cortical localization?

Answer 1

• A theory developed in 19th century Europe that states that certain cognitive functions are localized to certain brain areas
• Important due to being a breakthrough in neuroscience and understanding of the brain that allows for better diagnosis and treatment. Can be illustrated in the case of Broca’s patient Tan that had damage in a specific area combined with symptoms of not being able to produce speech aside from the word “tan” but could understand everything. While cortical localization did not help him specifically, the breakthrough achieved through that knowledge benefitted many future patients with neurological issues

Question 2

11) Tan?

Answer 2

• A patient of Paul Broca’s from 19th century France who could understand speech but not produce it except the word “Tan”
• Important for psychology due to providing substantial evidence for the cortical localization theory. Because of the damage being localized to a specific area Broca was able to theorize about localization of the speech function which later led to the establishment of the Broca’s area and strengthening of the localization theory which benefited many future patients with neurological issues

Question 3

12) Phineas Gage?

Answer 3

• A man from 19th century America who became famous for staying alive and functional after having a metal rod go through his skull
• While surviving a metal rod blasting through his skull made him a fascinating case to psychologists, the importance of his case lies in the reporting of his story. Due to the information about his life after the incident not being easily available many textbooks simply report on him being alive but not being able to perform activities to take care of himself such as having a job, which, as we know from the podcast, did not turn out to be true. The case shows the importance of thorough research needed prior to making a claim about the case’s outcome, especially in such high-profile cases.

Question 4

13) Psychophysics?

Answer 4

• A field that measures the relationships between stimuli in the external world (physical events) and the person’s perception and experience of those stimuli (psychological events). Started with a German physicist Fechner in the mid-19th century.
• By showing that physical and psychological experiences are different through examples like comparing a pound of lead and feathers the establishment of the field allowed to warrant the existence of psychology as a separate science. Leading to important discoveries such as Weber’s law and Fechner’s law, the field provided early experimental psychology with tools to answer questions of sensation, perception, thinking, memory and learning.

Question 5

14 ) Weber Law?

Answer 5

• Principle created by German physiologist Weber in the mid-19th century. Allows to express the amount of change necessary for the subject to perceive a stimulus as different
• Weber’s Law states that the just noticeable difference (JND) between two stimuli is proportional to the magnitude of the stimuli. In simpler terms, it means that the amount of change needed for a person to notice a difference between two stimuli depends on the original intensity of the stimuli. This law was influential because it provided a mathematical framework for understanding how humans perceive differences in sensory stimuli, such as weight, brightness, sound, or taste. By quantifying the relationship between stimulus intensity and perception, Weber’s Law laid the groundwork for the development of psychophysics, which explores the relationship between physical stimuli and subjective perceptions, contributing to our understanding of sensory processing and perception.

Question 6

15) Trepanation?

Answer 6

• Trepanation is a surgical procedure involving the drilling or scraping of a hole into the skull. It dates back to ancient times and was performed for various reasons, including treating head injuries, relieving pressure from swelling, and possibly even as a ritualistic or religious practice.
• While not directly influential to the field of psychology in terms of contributing to our understanding of the mind, trepanation provides insight into ancient medical practices, cultural beliefs, and the evolution of surgical techniques. Studying trepanation helps historians and researchers understand how early civilizations perceived and attempted to treat conditions related to the brain and head injuries, offering valuable historical context for the development of medical and psychological thought.

Question 7

16) Hermann Helmholtz?

Answer 7

• German physician from 19th century who made big contribution to the nerve conductance theory
• Was able to measure the speed of nerve conductance through electrical nerve stimulation even though it was thought to be impossible to do. Because of his discovery, his student Wundt was able to conduct research on the measurement of the speed of mental processes which was the earliest psychological research and could not have been done without Helmholtz’s discovery

Question 8

17) Specificity of the nerves?

Answer 8

• A set of theories developed in 19th century Europe that certain nerves carried certain information. Mainly promoted through the Bell-Magendie law and the law of specific energies.
• Bell-Magendie law specifically was stating that sensation information was carried to the brain through dorsal nerves and motor information was carried from the brain through the ventral nerves. Important to psychology due to its use in the stimulus-response experiments that allowed to advance the scientific psychology further

Question 9

18) Gustav Fechner?

Answer 9

• A German physicist of the mid-19th century who came up with the concept of psychophysics which states that it’s possible to measure the relationship between the physical and psychological worlds with great precision.
• Aside from coming up with the idea of psychophysics Fechner revised Weber’s law into Fechner’s law which led to a decade of research in psychophysics measuring absolute and the threshold differences. Thus, his contributions both showed the need for psychology as a science (because of psychophysics) and provided the future science of experimental psychology with tools needed to answer questions of sensation, perception, thinking, memory and learning.

Question 10

19) Just Noticeable Difference (JND)?

Answer 10

• Principle created by German physiologist Weber in the mid-19th century. Allows to express the amount of change necessary for the subject to perceive a stimulus as different
• Weber’s Law states that the just noticeable difference (JND) between two stimuli is proportional to the magnitude of the stimuli. In simpler terms, it means that the amount of change needed for a person to notice a difference between two stimuli depends on the original intensity of the stimuli. This law was influential because it provided a mathematical framework for understanding how humans perceive differences in sensory stimuli, such as weight, brightness, sound, or taste. By quantifying the relationship between stimulus intensity and perception, Weber’s Law laid the groundwork for the development of psychophysics, which explores the relationship between physical stimuli and subjective perceptions, contributing to our understanding of sensory processing and perception.

Question 11

20) Place theory?

Answer 11

• A theory of pitch perception developed by Helmholtz in the mid-19th century (1863). Argues that different frequencies would have greatest impact at different places of the membrane resulting in the perception of lower of higher sound frequency
• Important due to being one of the first theories of pitch perception and, while modifications needed to be made, still remains valid today in accounting for the major aspect of auditory perception. Set the stage for the future physiology psychology field.

Question 12

21) Frequency theory?

Answer 12

• A theory of pitch perception developed by Rutherford in the late-19th century (1886). Argues that the firing of the impulses from the basilar membrane would match the frequency of the incoming sound.
• Important due to being one of the first theories of pitch perception and, while modifications needed to be made, still remains valid today in accounting for the major aspect of auditory perception. Set the stage for the future physiology psychology field.

Question 13

22) Broca?

Answer 13

• A surgeon and neuroscientist from 19th century France. Made an important impact on cortical localization of the brain theory through his famous patient “Tan” who could understand but not produce speech.
• As mentioned, Broca made an extremely important contribution to neuroscience through his work with “Tan” that allowed him to identify an area of the brain responsible for speech production. Following from that, he also developed a cranial topography technique which allowed him to predict which brain regions are underneath certain skull landmarks, thereby making brain surgery safer