At the time claimant terminated her employment, 8-41-301(2)(a) provided, in pertinent part, as follows: A claim for mental impairment must be proven by evidence supported by the testimony of a licensed physician or psychologist. For purposes of this subsection (2), 'mental impairment' means a disability arising from an accidental injury arising out of and in the course of employment when the accidental injury involves no physical injury and consists of a psychologically traumatic event that is generally outside of a worker's usual experience and would evoke significant symptoms of distress in a worker in similar circumstances. Colo. Sess. Laws 1991, ch. 219, 8-41-301(2)(a) at 1294. Claimant argues that, because the stresses of her job led to chest pains and an elevated blood pressure, such physical symptoms constituted a "physical injury" under 8-41-301(2)(a). We disagree. In Oberle v. Industrial Claim Appeals Office, 919 P.2d 918 (Colo. App. 1996), it was held that the "physical injury" referred to by the statute need not be one that results in a physical impairment or disability. Hence, the fact that the claimant there had suffered no permanent disability from a sexual assault did not mean that the mental trauma suffered as a result of that attack was not caused by a physical injury. At the same time, however, the Oberle court agreed with the proposition that there is a difference "between cases in which physical injury causes mental impairment ('mental-physical') and those where impairment follows solely an emotional stimulus ('mental-mental'). " Oberle v. Industrial Claims Appeals Office, supra, 919 P.2d at 920.