def augment_data(meta, response_left, stimulus):
    """Augment meta data with fields for specific cases

    Args:
        meta: DataFrame
        response_left: ndarray
            1 if subject made a left_response / yes response
        stimulus: ndarray
            1 if a left_response is correct
    """
    # add columns:
    meta["all"] = 1

    meta["left"] = response_left.astype(int)
    meta["right"] = (~response_left).astype(int)

    meta["hit"] = ((response_left == 1) & (stimulus == 1)).astype(int)
    meta["fa"] = ((response_left == 1) & (stimulus == 0)).astype(int)
    meta["miss"] = ((response_left == 0) & (stimulus == 1)).astype(int)
    meta["cr"] = ((response_left == 0) & (stimulus == 0)).astype(int)
    return meta