Sensory, Attentional and Perceptual Processes

Sensory, Attentional and Perceptual Processes, from Class 11 Psychology, Psychology, and the NCERT curriculum, explains how human beings gather, select, and interpret information from the world around them. The chapter introduces the three fundamental cognitive processes—sensation, attention, and perception—which work together to help individuals understand their external and internal environments. Students learn about various sense organs, sensory receptors, sense modalities, psychophysics, absolute threshold, difference threshold, and the functional limitations of sensory systems. The chapter highlights how sensory information forms the foundation of all human knowledge and behaviour.
 

The chapter further explores attentional processes, including selective attention, sustained attention, and divided attention. It examines factors that influence attention, such as stimulus characteristics, motivation, interests, attitudes, and preparatory sets. Important theories of attention, including Broadbent’s Filter Theory, Treisman’s Filter-Attenuation Theory, and Johnston and Heinz’s Multimode Theory, are discussed. Students also study practical aspects of attention such as span of attention, vigilance, automatic processing, and Attention Deficit Hyperactivity Disorder (ADHD). These concepts help explain how individuals focus on relevant information while filtering out distractions in everyday situations.
 

The chapter concludes with a detailed study of perception, explaining how people organise and interpret sensory information to create meaningful experiences. Learners explore Gestalt principles of perceptual organisation, figure-ground segregation, depth and distance perception, monocular and binocular cues, perceptual constancies, and visual illusions such as the Muller-Lyer and Vertical-Horizontal illusions. The role of motivation, expectations, cognitive styles, cultural experiences, and socio-cultural influences in shaping perception is also emphasized. By studying this chapter, students develop the ability to analyse how people perceive reality, understand perceptual differences, and apply psychological principles to real-life situations involving attention, sensation, and perception.