Perception is the ability to sense what is happening in the world. It includes deep unconscious awareness. If something has been sensed on any level, that thing has been perceived. Thought is a part of perception. People perceive events through all their senses, and the majority of events they sense without being consciously aware of them, yet they have still perceived the events. Conscious awareness makes up only a fraction of all of people’s perceived events. In this way, perception encompasses a vast amount of information on a unconscious level – far too much information to control consciously.
Human emotions, which are processed consciously, typically start with a perception in the neo-cortex. The perception is then relayed to trigger sub-cortical brain regions that execute instinctive psychological, physiological and biological reactions (e.g. smiling, heart-rate or focusing the mind) associated with the perceived event. These processes cause people to feel aroused and motivated to many different forms of behaviour without having to think about it. People sense something and then have an emotion as a motivational response to the perceived event. Perceptions create emotions.
The Necker cube below amusingly illustrates this point visually. The cube can be perceived as pointing in two different directions. It depends on what lines are perceived to be in the foreground.
Look at the angles in the centre of the cube. Depending on which of those centre angles are perceived to be in the foreground, will determine which way the cube is pointing.

Necker Cube Image

When you can perceive the different optical illusions, imagine the cube is moving towards you. What way do you feel like moving out of the way? It depends on the position you perceive the cube to be in, right? Perception informs instincts of what is going on and people get feelings or emotions to prompt them to take a particular course of action depending on those perceptions. The different perceptions prompt people to move in different directions. When the cube is imagined to be moving speedily towards people, they are prompted to use specific hand and leg movements to avoid the object safely. This simply demonstrates that emotional motivation is linked to instinctive reactions for an animal’s welfare. When an event is sudden and unexpected, higher priority is given to more physically instinctive reactions whilst higher brain faculties are left out of the loop. This is an evolutionary adaptation to save time when prompting immediate movement when in the presence of an imminent physical threat.

Emotions evolved as psycho-neurobiological adaptations to perceived events.

The perceptions may be true or false, realistic or fantasies, or simply innaccurate, but if the perception is believed the associated evolutionary emotional adaptation is experienced. Appropriate emotional responses to the world are based on accurate perceptions of reality. This is coupled with how much conviction people place in those perceptions. Many instincts have incredibly sensitive perceptual triggers that respond to the intensity of perceptual convictions. If people believe a perception, they feel the emotion whether that perception is true or not.

Emotions evolve to serve perception.

Perception