Vasconcelos only took on the captaincy at the start of the summer, replacing Adam Rossington who had been in charge since midway through the 2019 season.
The South African-born player steps back having captained the team eight times in the LV= Insurance County Championship Division One, leading Northants to one win, one defeat and six draws.
The team is currently fifth in the table, 31 points above the bottom two, so there is no issue with Vasconcelos's record or captaincy.
But the player himself feels the extra pressures and responsibilities in the job have affected his own performances, and he now wants to 'focus on my batting'.
“This has been a really tough decision to make.” said Vasconcelos, who earlier this month signed a new contract at Wantage Road.
“It’s been an honour and a privilege being the captain of this club and one that I am extremely proud of however I truly believe that this is the best decision for myself as well as the club moving forward.
“We are in a great place in red ball cricket and hopefully we can kick on and continue climbing up the table.
"Now I can fully focus on my batting and scoring big runs again for Northamptonshire.”
Head coach Sadler backed Vasconcelos and his decision.
“The club fully support Ricardo’s decision to step back and understand the reasons behind it," he said.
"We’re all looking forward to seeing him back at his best with the bat and thank him for the work and effort he put in as a leader.”
Young steps straight into the role and will captain the team in Tuesday's four-day clash with Lancashire at the County Ground (start 11am).
The Kiwi will be playing his first match for the club since mid-May, having spent the past couple of months on international duty.