How do I access a constructor “this” variable? [duplicate]

In my updateCamera(event) function, I am trying to access this.camera as can be shown in my constructor. Unfortunately, it’s undefined in that function, I assume it’s a scope issue, but I’m not sure how to solve it. Any ideas? Thank you.

export default class Experience {
    constructor(options = {}) {
        this.camera = new Camera();
        // removed unnecessary stuff
        this.onMouseDrag();
    }

    updateCamera(event) {
        console.log(this.camera); //Prints "undefined" in the console
        this.camera.position.x = (event.clientX / window.innerWidth) * 2 - 1;
    }

    onMouseDrag() {
        window.addEventListener("mousedown", () => {
            window.addEventListener("mousemove", this.updateCamera);
        });
        window.addEventListener("mouseup", () => {
            window.removeEventListener("mousemove", this.updateCamera);
        });
    }