The next few chapters in this book focus on the field of cognitive psychology. Cognitive psychology is the study of the mental processes and activities involved in acquiring, processing, storing, and using information. It encompasses a wide range of functions such as sensation and perception, attention, memory, language, problem-solving, decision-making, reasoning and intelligence. This chapter focuses on one subfield of cognitive psychology—sensation and perception. But, what does that mean exactly? Imagine standing on a city street corner (like the one in Figure 5.1). You might notice the rapid movement of the cars and people as they go about their business, the sound of a street musician’s melody or a horn honking in the distance, the smell of exhaust fumes or of food being sold by a nearby vendor, and the sensation of hard pavement under your feet. You are experiencing sensation and perception!

We rely on our sensory systems to provide important information about our surroundings. We use this information to successfully navigate and interact with our environment so that we can find nourishment, seek shelter, maintain social relationships, and avoid potentially dangerous situations.

This chapter will provide an overview of how sensory information is received and processed by the nervous system and how that affects our conscious experience of the world. We begin with the distinction between sensation and perception. Then we give an overview of the basic structure and function of the major sensory systems. Along the way, we will consider how culture and other experiences, influence our perceptions of the world around us.

Learning Objectives

• Distinguish between sensation and perception
• Discuss the roles that attention, motivation, experience and culture play in perception
• Describe the basic anatomy of the visual system
• Discuss how rods and cones contribute to different aspects of vision
• Describe the trichromatic and opponent process theories of color vision
• Describe how monocular and binocular cues are used in the perception of depth
• Explain how Gestalt psychology influenced the field of sensation and perception
• Describe basic Gestalt principles of grouping
• Explain the concept of perceptual set and its influence on perception
• Explain the concept of implicit bias and its effects on perception
• Describe the basic anatomy and function of the auditory system
• Explain how we encode and perceive pitch
• Discuss how we localize sound
• Describe the basic functions of the chemical senses
• Explain the basic functions of the somatosensory, nociceptive, and thermoceptive sensory systems
• Describe the basic functions of the vestibular, proprioceptive, and kinesthetic sensory systems
• Describe the importance of multisensory neurons in perception