Operating as an assistant at the Solvay Institute of Physiology, she lectured and conducted research into muscle and nervous system fatigue.

This led her to conduct investigations on children, examining how educational facilities could optimize the potential of their students by drawing on scientific methodology.

Józefa Franciszka Joteykówna was born on 29 January 1866 in Poczujki [ru], Romanov volost of the Skvyra uezd in Kiev Governorate of the Russian Empire (today village of Pochuiky is located in Popilnia Raion, Zhytomyr Oblast).

Her family, which included a sister, Zofia, and two brothers Mieczysław and Tadeusz [pl], was descended from landowning Lithuanian nobility and members of the Polish intellectual elite.

[2][3] When she arrived in Switzerland, she cut her hair short, wore tailored dresses with a more masculine style, and was rumored to smoke.

[5] She published papers on physiology and her research into the effects of anesthesia by means of ether or chloroform on muscles, nerves, and the nervous system.

She convinced Joteyko, whom she referred to as her towarzyszka życia (life companion),[Notes 1] with the promise that they could write letters and visit each other.

[15] Though she continued to research physiology, Joteyko began lecturing on pedagogical psychology at teacher's seminars in Charleroi and Mons.

In 1908, she founded and became editor of the Revue Psychologique, a journal which explored developments in the field of psychology from a scientific and educational perspective.

[2] Through her work there, she met and began collaborating with a young, Georgian scientist, Varia Kipiani, who served as a secretary to the Revue.

The two women carried out joint research on vegetarianism, to which they both adhered[16] and were awarded the 1908 Vernois Prize of the Académie Nationale de Médecine.

[10] Collaborating with Charles Henry, she sought to use scientific study and instruments to graph social phenomena and draw comparisons with biological data.

By measuring and graphing, for example, physical and intellectual fatigue, Joteyko argued that military training would produce better results if limited to six months.

[19] These studies led her to investigations on children and how educational facilities could apply scientific methods to improve and optimize the potential of their students.

[21] Joteyko, who led the Faculty until World War I broke out,[2] became a mentor to Grzegorzewska and was a significant influence on her scientific development.

[15][26][27] Joteyko believed that the rejection was caused by an aversion to women in Polish scientific circles, as well as the fact that she lived with long-term female partners.

[2] Using various instruments, she taught her students to measure fine motor skills, rates of reaction to stimuli, and spatial orientation, as well as analyzing psychological results from such examinations as the Binet-Simon intelligence, Otis mental-ability, and Stanford educational tests.

She pressed for the creation of schools which addressed their particular needs and allowed students to achieve the maximum education under conditions suitable to their mental abilities.

[33] She stressed that schools should be secular, believing that religion was a matter of personal preference and its introduction into education limited the development of tolerance and compassion for others.

[2] In 1926, a year after the Pedagogical Institute closed,[24] she began teaching at the Free Polish University, but was unable to conduct research there as it did not have a laboratory.

[2] Joteyko presented her last lecture at the State Institute of Special Education in 1926 and founded the quarterly Polskie Archiwum Psychologii (Polish Archives of Psychology), serving as its editor.

[1] At the time of her death, Joteyko was widely respected for her work, and, along with Marie Curie, was one of the most internationally recognized Polish scientists.

She became an honorary member of the Accademia di fisica e chimica (Academy of Physics and Chemistry) of Palermo and toward the end of her life served as chair of the Polish Society of Psychotechnics (Polskie Towarzystwo Psychotechniczne).