The Reds remain in the Sky Bet League One drop zone - and without a home win since September - after going down to play-off chasing Wigan.
A goal in each half ensured the Reds’ mini-revival was halted and manager Lee Johnson was again booed off at the final whistle.
The Reds played their part in an enterprising first period at a dark and gloomy Oakwell.
Certainly the opening 20 minutes were entertaining, with both sides trading chances almost at will.
Ivan Toney went close for the hosts when he flicked Marley Watkins’ cross narrowly wide, while Wigan responded with Will Grigg forcing Adam Davies into a smart save from an acute angle.
The unmarked Grigg then planted a free header wide from barely eight yards.
Back came Barnsley, and they went close when Sam Winnall dived in bravely to head a cross from Adam Hammill inches over the crossbar.
The deadlock was broken in the 19th minute by 2013 FA Cup winners Wigan.
Michael Jacobs played a super through-ball to Andy Kellett, who clipped a neat effort over the body of Davies to register his first Athletic goal.
The hosts opened the second period encouragingly. Just two minutes in, Hourihane found space on the edge of the Wigan box, only to stab a right-foot shot a couple of feet wide.
Max Power was much closer at the other end as Athletic replied, then Davies came to the Reds’ rescue to thwart Kellett, who had ran on to meet another Jacobs through-ball.
Wigan’s victory was wrapped up with four minutes to go.
The Reds’ defence stood motionless as ‘keeper Jussi Jaaskelainen hit a huge clearance forward, allowing sub Yanic Wildschut to nip in and round Davies before slotting easily into an empty net.
Barnsley (4-4-2): Davies; Wabara, Long, Nyatanga, White; Watkins, Pearson, Hourihane, Hammill, Winnall, Toney. Subs: Townsend, Mawson, Williams, Isgrove, Bree, Jackson, Abbott.
Wigan (4-5-1): Jaaskelainen; James, Pearce, Daniels, Kellett; Love, Power, Perkins, Morgan, Jacobs; Grigg. Subs: Nicholls, Barnett, Chow, Davies, Revell, Hiwula, Wildschut.
Referee: Sebastian Stockbridge (Tyne & Wear).