"fundamental in understanding" is correct and usable in written English.
You can use it when you want to emphasize the importance of understanding something. For example: "It is fundamental in understanding the core concepts of this subject."
But I think it will be fundamental in understanding the sense of smell".
This inhibition has been observed as IPSPs arising shortly after EPSPs [36], and seems to be fundamental in understanding the response of PCs [37, 38].
The assessment of flow regime alterations is fundamental in understanding the potential impact of reservoirs and other water infrastructures on aquatic ecosystems and biota.
Interpolating the orientation of the maximum horizontal compressive stress with a well-established procedure is fundamental in understanding the present-day stress field.
Li et al. (2006) argues that history and time are fundamental in understanding Chinese SMEs and categorizes the evolution of Chinese SMEs in four phases: "early stage" (1949 1957)",growth and fluctuation" (1958 1963), "innovative transformation" (1978 1996) and "rapid growth" (1997 - onward).
Accurate cutting-force measurements appear to be the key information in most of the machining related studies as they are fundamental in understanding the cutting processes, optimizing the cutting operations and evaluating the presence of instabilities that could affect the effectiveness of cutting processes.
It is expected that this work could provide important fundamentals in understanding mechanical behaviour of hydrogen stored SWNCTs subjected to compression that could assist in the development of effective on-board hydrogen storage systems for fuel cells.
One of the fundamental goals in understanding schizophrenia is linking the observable symptoms to the underlying unobservable pathophysiology.
The discovery of a new particle, decades after the Higgs was predicted, fills a fundamental gap in understanding the universe.
Some of the earliest collections given to the society were of fundamental importance in understanding the new nation's social and religious background, including family papers of Cotton Mather and his descendants.
The judge said some of the questions from the jury had shown a "fundamental deficit in understanding" of its role.
