Date: 201510
Local time of day: 1201-1800
Location: ATL.Airport, GA
Flight conditions: VMC
Light: Daylight
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class E A80
ATC / advisory: TRACON A80
Second aircraft: B767 Undifferentiated or Other Model
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Wake Vortex Encounter
Detector: Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Contributing factors: Environment - Non Weather Related; Human Factors; Procedure
Primary problem: Ambiguous

Narrative: During our descent on the KOLTT ONE RNAV ARRIVAL and just before crossing ERLIN; we encountered the wake of the aircraft preceding us. The wake turbulence was the second worst I have ever experienced. We later found out that the aircraft ahead was a B767. Our CRJ900 rolled abruptly and violently to the right about 30 to 40 degrees. I disconnected the autopilot and muscled the airplane back to level. When the wake turbulence event was over; I quickly called the cabin to see if the FAs were ok. I then made a PA to the passengers to apologize for the event and explain what had happened.At about that time center switched us to ATL approach control. We checked in but I really didn't hear the controller assign us a runway like they usually do. We had planned for RWY 8L and had it programmed in the FMS. We were both so frazzled by the brutal wake turbulence that even if the controller had assigned us a RWY; we did not hear it or read it back. If my FO read it back; I did not hear it. He doesn't remember a RWY assigned either; (a few weeks ago; an approach controller failed to assign us a RWY on initial check-in). I was about to ask my FO to query the controller about which RWY we could expect when the controller asked us to descend to 8;000 FT and were we going to NAVVY intersection. I quickly programmed the ILS to 9R in the FMS which brought up the NAVVY waypoint and turned the airplane towards the fix. That's when I realized we had either not been assigned a RWY; or not heard it/read it back; or heard it and read it back but didn't take action on it because the wake had jarred us so badly. This whole event from the time of encountering the wake to turning towards NAVVY took place in the span of 3 or 4 minutes.THREATS: The wake turbulence; the KOLTT ARRIVAL flight path being runway dependent. The fact that our hands were full right when frequency switch occurred.ERRORS: I don't know if the controller assigned us a runway. He probably did; but it was lost on us. Another error was that I had suspected we might encounter wake turbulence; but earlier and closer to Chattanooga. ATC wanted us to fly fast and asked us to keep our speed up as long as we could until we had to slow down to make the crossing restriction of 250 KTS at ERLIN. We complied but that put us only 7-8 miles behind the 767. I felt uncomfortable when TCAS showed him at less than the usual 10 mile separation descending on the arrival.UAS: A possible course deviation from what the controller expected from us.I will raise a concern with ATC about the proximity of the traffic ahead on the arrival. By the way; I have had more combined wake turbulence encounters descending into ATL in the last few months than I have in the last nearly 20 years of flying here. I will most certainly query the controller promptly in the future if a runway isn't assigned on initial check-in; because the arrival flight path is runway dependent.


Second narrative: During the wake turbulence event; both of our primary concerns was of maintaining positive control of the aircraft; ensuring the safety of our cabin crew and passengers; and minimizing the effects of invisible wake turbulence that had no definitive end presented.


Synopsis: CRJ-900 flight crew reported encountering wake turbulence on arrival to ATL in trail of a B767 which distracted the crew enough that they missed a clearance.