is measuring an enduring trait, while the question "How do you feel right now at this very moment?" is a measure for emotional states. Another way to categorize the measures is to differentiate between distinct-states approach and dimensional approach. Examples of measures using distinct-states approach include theProfile of Mood States (POMS2), and the State-Trait Anxiety Inventory. Dimensional approach adopts the psychological constructionist tradition, but has been criticized for assuming the “emotions can be reduced to pleasant and unpleasant states or that affect alone provides a sufficient explanation for emotion”. Examples of the dimensional approach measures include the Positive and Negative Affect Schedule (PANAS) and the Self-Assessment Manikin. A three-step process is proposed for choosing an affective measure. Firstly, consider what the specific construct it is that you want to measure. Secondly, choosing the theoretical framework in accordance with the construct. Lastly, evaluate the psychometric feature of the measures available (e.g. reliability, validity, etc.). The Affective Slider is an empirically-validated digital scale for the self-assessment of affect composed of two slider controls that measure basic emotions in terms of pleasure and arousal, which constitute a bidimensional emotional space called core affect, that can be used to map more complex conscious emotional states. One frequently used measure for general affective states is the Positive and Negative Affect Schedule (PANAS). Participants completing the PANAS are asked to rate the extent to which they experienced each out of 20 emotions on a 5-point Likert Scale ranging from "very slightly" to "very much". The exact instructions may vary according to the purpose of the study: Participants may be asked how they feel "right now" or during longer periods of time (e.g. during the past year). Half of the presented emotion words concern negative affect (distressed, upset, guilty, ashamed, hostile, irritable, nervous, jittery, scared, afraid), the other half positive affect (interested, alert, attentive, excited, enthusiastic, inspired, proud, determined, strong, active). The PANAS has been regarded as a highly reliable measure for non-clinical populations. Independent validation studies indicate that the measure demonstrates excellent construct validity. Regardless of its wide use, PANAS has several limitations that researchers should be aware of in the selection process. As the original theory suggests, affect is a bipolar construct with a composite of valence and arousal. However, the categorization of positive emotion and negative emotion displays unipolarity that is contrary to its theoretical base.