Welcome to Perception and Illusions! In this course, we explore how your brain actively constructs reality. Through engaging visual and sensory illusions, I’ll show you how bottom-up and top-down processing shape what you see, hear, and feel—and why your perceptions might not be as accurate as you think.

In this course, we explore how illusions reveal the brain’s role in shaping perception. You’ll learn the difference between sensation and perception, and how top-down and bottom-up processing work together. Through vivid examples, we uncover how raw sensory input and prior knowledge combine to construct your experience of reality.

In this section, we explore key principles of perception and how they shape sensory experience. We examine top-down and bottom-up processing, along with adaptation, contrast effects, habituation, and context. You’ll learn how the brain organizes input and integrates multiple senses to create a unified experience.

In this section, we explore the visual, auditory, and somatosensory systems and how they shape perception. We trace visual info from the retina to pathways for object recognition and spatial awareness, examine how the auditory system organizes sound by pitch and frequency, and look at how the somatosensory system processes body signals. We highlight key perceptual phenomena and the brain regions involved in organizing and interpreting sensory input.

In this section, we dive deep into the weird and wonderful world of perceptual illusions—mind-bending phenomena that reveal just how much your brain does behind the scenes. You’ll explore how bottom-up processing drives perception, and how simple contrasts and sensory adaptations can lead to surprising effects.

In this section, we explore how your mind fills in the gaps to create meaning from incomplete or ambiguous sensory input. You’ll learn how we perceive clarity in low-res images, how the brain compensates for blind spots, and why illusions like the Ponzo and Leaning Tower work so well. We’ll also dive into the Stroop effect, pareidolia (seeing faces in clouds, anyone?), and the brain’s knack for finding patterns in sound.

In this section, we explore visual perception through illusions that challenge how we see. Topics include blindsight, where people navigate without conscious vision, and illusions like Zöllner, Café Wall, and Hering, which show how context distorts lines. We also examine the Müller-Lyer and Ebbinghaus illusions, color constancy, motion effects, and ambiguous images like Rubin’s Vase and the Necker Cube.

In this section, we explore auditory perception through illusions that blend top-down and bottom-up processing. You’ll encounter the Missing Fundamental Illusion, where the brain fills in absent pitches, and the Scale Illusion, which forms a smooth stream from alternating notes. We also dive into the Shepherd Scale, which creates the illusion of endless pitch rise.

In this section, we explore somatosensory illusions, where top-down expectations and bottom-up input shape how we perceive touch and force. You’ll encounter illusions like Aristotle’s, Pinocchio, and the Cutaneous Rabbit, along with the Size-Weight Illusion and Thermal Referral, which reveal the brain’s predictive coding.

In this section, we explore multimodal phenomena, where senses interact in surprising ways. You’ll see how sound alters vision in the double flash illusion, explore synesthesia, and learn how the McGurk effect and ventriloquism shift perception. We also cover the rubber hand and mirror box illusions, revealing the brain’s power to integrate sensory input and construct reality.

In this section, we explore neuropsychological disorders and what they reveal about how the brain constructs reality. You’ll learn about agnosia, prosopagnosia, Capgras syndrome, and hemi-neglect, along with inattentional and change blindness. These conditions show how attention, experience, and brain function shape what we see—and what we miss.

Congratulations on completing the Neuroscience of Perception & Illusions course! Explore recommended classic neuroscience textbooks for further reading and consider enrolling in advanced classes such as Neuroscience of Pain, Trauma Informed Care, and Neuroscience of Vision.

Complete the Knowledge Check to receive your certificate of completion and become eligible to receive (1.5) CE Credit Hours.