From the above linked paper "Emotions in Plato and Aristotle", discussing Aristotle: (the author uses "affections" in place of "emotions")
"The two Ethics introduce pleasure or pain, or pleasure and pain, in order to generalize from lists of affections. Thus we read, ‘By the affections I mean desire (epithumia), anger, fear, confidence, envy, joy, love, hatred, longing, emulation, pity, and in general things that are accompanied by pleasure or pain’ (NE 2.5.1105b21-3); but also, ‘By the affections I mean such things as anger, fear, shame, desire, and in general things that, as such, give rise for the most part to perceptual pleasure and pain (EE 2.2.1220b12-14). Presumably it is not a coincidence that the Eudemian Ethics adds both the qualification ‘for the most part’ and the specification ‘perceptual’: Aristotle must think that a special kind of pleasure or pain attaches to most affections, though not all. The Physics identifies the affections with changes in the soul’s perceptual part (to aisthêtikon morion) that involve bodily pleasures and pains excited by action, memory, or anticipation (7.3.247a3-9). Such pleasures and pains are excited by sensible things through perception or imagination (a9-17). They arise from their location within that part of the soul which Aristotle elsewhere calls ‘the perceptual and desirous’ (EE 2.2.1219b23): they are not merely sensible because conscious, but sensory in that they connect closely with sense-perception and imagination within the affective soul (to pathêtikon morion, Pol. 1.5.1254b8). Many of the affections involve imagination (phantasia) in the service of memory and expectation; this connects them with the pleasures that follow on imagination as a weak form of perception (Rhet. 1.11.1370a27-32)."
"It is true that there is no explicit mention of belief in the initial definition of anger (2.2.1378a30-2); but belief is implicit in mention of desire (orexis), given that such orexis is equated with ‘aiming at’ (ephiesthai), which is taken to presuppose believing, and not just imagining, that an end is attainable."