Jon Willis Jacklet

Jon W. Jacklet, distinguished neuroscientist and family man, died in his sleep at home on October 23, 2025 at the age of 90.

Jacklet was born on April 16, 1935 in Springfield Gardens, New York. His family moved to Pennsylvania when he was five, and he attended Ambridge High School, where he practiced boxing and gymnastics and starred as a pole vaulter on the track and field team.

After graduating from high school in June of 1953, Jacklet worked in the local steel mill and found work on an ocean freighter bound for Europe and North Africa. He traveled to Italy, Cyprus, Libya, and Morocco before sailing back to the U.S. from Sicily. Shortly after his return, he enlisted in the U.S. Marine Corps, beginning his service in January of 1954. He trained in aerial navigation in Jacksonville, Florida, made sergeant, and was honorably discharged in January of 1957.

Upon leaving the Marine Corps, Jacklet took a job as a deckhand on a sailboat, navigating the Caribbean from Florida to the Bahamas. He then moved west to find work in the Oregon timber industry, and entered the University of Oregon on the G.I. Bill in the fall of 1957.

Jacklet studied geology and biology as an undergraduate student. He also starred on the university’s rugby team, earning praise as a “dark-haired speed demon” in a March 9, 1962 article from the Oregon Daily Emerald. He entered graduate school in the biology department in September of 1962.

At the start of his graduate studies, Jacklet met Alice Carleton, who had driven cross country from New England to enter the same biology program. They were wedded that December, the beginning of a marriage that would last more than 62 years. They had three children: Alan, born in 1963; Ben, born in 1966; and Jessica, born in 1970.

Jacklet earned his PhD in 1966 in Oregon and moved to Pasadena, California in 1967 to pursue his post doctorate studies at Caltech. He accepted a position in the biology department at the State University of New York at Albany in 1969, where he worked for nearly 40 years.

Jon and Alice bought a home in Altamont, New York, in 1970. There they raised their three children and cared for a diverse collection of family dogs, cats, rabbits, fish, and turtles. During this period, Jacklet made full professor, earned numerous grants from the National Science Foundation and the National Institutes of Health, and published numerous scientific papers including some highly significant neuroscience findings. He served as editor of the 1989 book “Neuronal and Cellular Oscillators.”

Jacklet’s primary object of study was Aplysia, a marine organism with a very simple nervous system. Using electrical readings and circadian rhythms, Jacklet and his mentees studied neural plasticity, memory, and specific functions of the nervous system.

One of Jacklet’s most significant discoveries involved the key function of nitric oxide as a neuronal messenger. He proved that neurons communicate not only through direct synaptic transmission at specialized contact points, but also chemically—with nitric oxide serving as a direct chemical messenger. This chemical process enables neurons to impact other neurons and cells without contacting them directly.

Jacklet attended numerous international conferences related to his research, and he collaborated with colleagues on sabbatical trips to Mexico City, Tahiti, the Woods Hole Oceanographic Institute, and Calgary, Canada. He mentored numerous graduate students over his career, many of whom went on to pursue distinguished academic research careers of their own.

Although he did not grow up playing tennis or skiing, Jacklet became an accomplished Nordic skier and tennis player as an adult, winning races and tournaments. He also was a licensed pilot, and once flew the family to Cooperstown, New York to visit the Baseball Hall of Fame and attend the opera. He later switched from small planes to non-motorized gliders, pursuing thermals and lift in Saratoga Springs, N.Y., the South Island of New Zealand, and the Alvord Desert in Oregon.

Jon and Alice Jacklet retired and moved to Portland, Oregon in 2007. Jon spent his retirement soaring, singing, and spending time with family. He was an active member of the Willamette Valley Soaring Club, an enthusiastic table tennis and billiards player, and an accomplished singer featured in numerous performances. He also supported many grassroots political and environmental organizations with regular contributions. He celebrated his 90th birthday in Portland with family, cake, and singing.

Jon Jacklet is survived by, and deeply missed by, his wife, Alice; his children, Alan, Ben, and Jessica; his sister Sylvia and brother David; his grandchildren Emily, Andoni, Melina, Lily, and Sabrina; his in-laws Connie, Christina, and Andy; his great-grandson Silas; and many more.