The Gunners lifted the FA Cup in August but have been unconvincing in the top flight, winning only 15 of 34 games this calendar year.
“It is a massive confidence boost for us,” he said. “Obviously we went through that really rough patch, but as soon as we got a win it gave us a lift.
“Now we’ve got another win and hopefully now we can go on a bit of a run, pick up points and climb up the table. Fingers crossed we can climb the league and get back into European places and push on.”
Despite having an extra day’s rest compared to Brighton, Arsenal produced a dismal first-half showing at the Amex Stadium.
Granit Xhaka’s off-target free-kick was the Gunners’ only attempt during an opening period in which they managed only two touches in Albion’s 18-yard box.
The visitors improved significantly in the second period and won courtesy of substitute Alexandre Lacazette scoring just 21 seconds after coming on.
Holding was unconcerned by the manner of the victory and suggested his side had been helped by a more favourable schedule.
“I think our last couple of games when we have lost, we have had so many attempts and not scored,” the 25-year-old said. If we have two touches in the box (in the first half) and still win, I’ll take that all day.
“To be fair, Brighton had it tough. I think they had 48 hours in between their games. We had that extra day to recover, which helped.”