CRJ-200 TURNED TO WRONG HDG ON APCH; CONFUSING ASSIGNED HDG WITH THE RWY ASSIGNMENT IN THE CLRNC.

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I WAS FLYING AT 10000 FT AND HDG APPROX 170 DEGS. I HAD BRIEFED THE CAPT OF OUR APCH AND LNDG IN CMH RWY 10L. THE CAPT CHKED ON WITH APCH CTL AND WAS GIVEN; I BELIEVE; 'TURN 195 DEGS; THIS WILL BE VECTORS FOR THE DOWNWIND TO RWY ONE-ZERO RIGHT; DSND AND MAINTAIN 4000 FT.' I BELIEVE THAT I HEARD THE 'ONE-ZERO' PART OF THE CLRNC AND SPUN IN 105 DEGS IN THE HDG KNOB INSTEAD OF 195 DEGS. I FLEW THE ERRONEOUS HDG AND DSNDED AND WONDERED WHY WE GOT A L TURN INSTEAD OF A R TURN FOR THE DOWNWIND VECTORS. I ASKED THE CAPT; 'DID HE SAY TURN ONE-ZERO-FIVE?' THE CAPT; BUSY WITH SETTING UP THE NEW RWY APCH PROC IN THE FMS AND RADIOS; SAID 'YES; ONE-ZERO-FIVE.' I FLEW THIS HDG FOR ABOUT 2 MINS AND WE RECEIVED A TCAS TA AND NOTED A CONTACT 3 MI TO OUR L AND 800 FT BELOW. JUST THEN APCH CALLED AND STATED 'WHAT HDG ARE YOU FLYING?' THE CAPT TOLD HIM 105 DEGS; AND APCH REPLIED; 'I TOLD YOU 195 DEGS AND THAT'S WHAT YOU READ BACK! TURN TO HDG 195 DEGS!' I BELIEVE THAT THIS HDG DEV WAS CAUSED BY SEVERAL FACTORS: I HAD A MINDSET OF LNDG ON RWY 10L; WHICH SEEMED LIKE THE MOST LIKELY RWY; GIVEN OUR APCH DIRECTION. WE HAD BRIEFED AND LOADED THE RWY 10L APCH INTO THE FMS AND NAV RADIOS. WHEN APCH GAVE THE INSTRUCTION; THERE MAY HAVE BEEN ADDITIONAL UNNECESSARY VERBIAGE AND AS HE WAS GIVING THE INSTRUCTION; I BEGAN THINKING ABOUT HOW WE WOULD HAVE TO HURRY AND BRIEF AND LOAD THE NEW RWY 10R APCH AND LNDG. I THINK; FOR THIS REASON; I TRANSFORMED THE ONE-ZERO PART OF THE CLRNC TO THE NEWLY ASSIGNED HDG AND FLEW 105 DEGS INSTEAD OF 195 DEGS. ALSO; SINCE OUR WORKLOAD INCREASED NOW DUE TO THE UNEXPECTED RWY; I BELIEVE THAT THE CAPT TRUSTED MY L TURN; EVEN WHEN I QUESTIONED HIM ABOUT IT; SINCE HE WAS BUSY SETTING UP THE NEW APCH. THIS TRUST MAY BE FURTHER EXPLAINED BECAUSE THE CAPT KNOWS THAT I HAVE OVER 4000 HRS AND HAVE 2000 HRS OR SO PART 121 PIC TIME AS WELL. THESE DAYS; IT'S NOT UNUSUAL FOR THIS CAPT TO HAVE TO FLY WITH VERY LOW TIME PLTS (UNDER 500 HRS TOTAL TIME; SINCE THAT'S WHAT THE REGIONALS ARE HIRING THESE DAYS). GIVEN THIS (AND I HAVE EXPERIENCED THIS 'RELAXATION' WHEN I WAS A CAPT AS WELL); I BELIEVE THAT A LITTLE BIT OF BLIND TRUST INTERFERED WITH OUR USUAL CHK-AND-BAL OP.