Arousal, excitement: red 33%, orange 20%, yellow 13%, …
Heller (1989)

Arousal is conceptualized here as a unitary emotional response dimension ranging from sleep to frantic excitement. This dimension is readily assessed with semantic differential measures. Data obtained using this technique have shown chat variations in the arousing quality of situations is indeed a primary and unitary factor. Several nonverbal measures have also been identified which are intercorrelated and essentially define a measure of responsiveness or arousal in social situations. These are vocal activity (including positive as well as negative), facial activity (including positive and negative expressions), speech rate, and speech volume. In considering the problems that are associated with physiological measures of arousal, Berlyne (1967) commented, “All this need not worry us unduly, although it certainly calls for circumspection, as long as we regard arousal as a dimension and not as a phenomenon-not, that is, as a process that goes on in one location in the central nervous system” (p. 12).
Thus, even though there is insufficient knowledge of the relations between the primary and secondary physiological measures of arousal (especially over a variety of situations), Berlyne’s (1960) definition of arousal still has considerable heuristic value. Further, as already noted, there is evidence showing a correlation of verbal reports of arousal or activity with physiological indexes of arousal.

Mehrabian & Russell (1974)

Novelty Seeking reflects a heritable bias in the initiation or activation of appetitive approach in response to novelty, approach to signals of reward, active avoidance of conditioned signals of punishment, and skilled escape from unconditioned punishment.

High Novelty Seeking: Impulsiveness, impulsive decision making, Impulsive sensation seeking, Extravagance, extravagance in approach to reward cues, quick loss of temper, avoidance of frustration, Exploratory excitability, Disorderliness. They are observed as exploratory activity in response to novelty, impulsiveness, extravagance in approach to cues of reward, and active avoidance of frustration. Individuals high in Novelty Seeking are quick-tempered, curious, easily bored, impulsive, extravagant, and disorderly.

Persons low in Novelty Seeking are slow tempered, uninquiring, stoical, reflective, frugal, reserved, tolerant of monotony, and orderly.
(Cloninger, 1994)

A sharp angle is associated with ‘shocking’ or ‘exciting’, because of the acute change in the direction of the movement. However, a rounded corner is seen more as ‘relaxed’ (Kreitler and Kreitler, 1972).

The size of an angle can be determined by measuring the angle that two lines make with each other. This angle can be expressed in both degrees and radiants. The larger the angle, the more blunt it is. And conversely, the smaller the angle between two lines, the sharper.

The emotional effect of sharp corners differs according to the application. When it comes to utensils, sharp corners can be perceived as dangerous, they can puncture or cut.

Blunt/sharp is classified as a HEIGHT dimension parameter because a shape with blunt lines comes often with a thick shape, while sharpness appears most of the time in a thin shape. Compare the thick/thin parameter.

(Inez Michiels, DSD, 2021)