NCERT Class 11 Psychology Introduction to Psychology: Chapter 4 — Sensory, Attentional and Perceptual Processes
This chapter from NCERT's Introduction to Psychology, Class 11, delves into Sensory, Attentional, and Perceptual Processes. It explains how our sense organs gather information from both external and internal environments, forming the basis of our knowledge. The chapter details the nature and varieties of stimuli, introducing the concept of sensation. It then explores attention, discussing its selective, divided, and sustained aspects, and factors influencing it, including Attention Deficit Hyperactivity Disorder. Finally, it examines perception, covering processing approaches, the perceiver's role, principles of organization, space and depth perception, perceptual constancies, illusions, and socio-cultural influences. Understanding these interconnected cognitive processes is crucial for comprehending how we interact with and make sense of the world around us, aiding CBSE students in their psychology studies.
Quick info
| Board | CBSE / NCERT |
|---|---|
| Class | Class 11 |
| Subject | Psychology |
| Book | Introduction to Psychology |
| Chapter | Chapter 4 — Sensory, Attentional and Perceptual Processes |
| Language | English |
| PDF type | NCERT Textbook |
| Session | CBSE 2026 |
| Reading time | 4 minutes |
| Word count | 783 |
Learning outcomes
- Understand the nature of sensory processes.
- Explain the processes and types of attention.
- Analyze the problems of form and space perception.
- Examine the role of socio-cultural factors in perception.
- Reflect on sensory, attentional, and perceptual processes in everyday life.
Vocabulary
| Word | Meaning |
|---|---|
| Receptors | Specialised cells or organs that detect stimuli from the environment or body. |
| Stimuli | Changes in the environment or body that can be detected by sensory organs. |
| Sensation | The process by which sensory receptors receive and transmit information from the environment. |
| Attention | The process of focusing consciousness on particular stimuli while ignoring others. |
| Perception | The process of organising, identifying, and interpreting sensory information to understand the world. |
| Cognition | Mental processes such as sensation, attention, perception, memory, and thinking. |
| Sense Modalities | Different types of sensory experiences, such as vision, hearing, touch, taste, and smell. |
| Selective Attention | The ability to focus on one stimulus while ignoring others. |
| Divided Attention | The ability to attend to two or more stimuli or tasks simultaneously. |
| Sustained Attention | The ability to maintain focus on a stimulus for an extended period. |
| Perceptual Constancies | The tendency to perceive objects as stable and unchanging despite changes in sensory input (e.g., size, shape, colour constancy). |
| Illusions | Misinterpretations of sensory information that lead to inaccurate perceptions. |
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Practice questions
- What is the role of sense organs in our knowledge of the world? Answer: Sense organs collect information from the external and internal worlds, which forms the basis of all our knowledge.
- Define attention and explain its importance. Answer: Attention is the process of focusing consciousness on particular stimuli. It is important because it helps us notice and register information carried by our sense organs.
- What is the difference between sensation and perception? Answer: Sensation is the initial process of receiving and transmitting sensory information, while perception is the subsequent process of organizing and interpreting that information to create meaning.
- Give an example of a stimulus that can be seen, heard, smelled, tasted, or touched. Answer: Example: A flower can be seen (colour, shape), smelled (fragrance), and touched (softness of petals).
Practice MCQs
Q1. Which of the following is NOT one of the three basic processes that form the basis of our knowledge of the world?
Explanation: The chapter explicitly states that sensation, attention, and perception are the three basic processes forming the basis of our knowledge of the world.
Q2. The process of organising, identifying, and interpreting sensory information to understand the world is called:
Explanation: Perception is defined as the process of organising, identifying, and interpreting sensory information to construct a meaningful understanding of the world.
Q3. Which type of attention involves focusing on one stimulus while ignoring others?
Explanation: Selective attention is the ability to focus on specific stimuli in the environment while filtering out irrelevant information.
Q4. Sensory receptors gather information from:
Explanation: The chapter states that sense organs (sensory receptors) collect information not only from the external world but also from our own body.
Q5. Which of the following is an example of a perceptual constancy?
Explanation: Perceptual constancies, such as size constancy, refer to the tendency to perceive objects as stable despite changes in the sensory input.
Frequently asked questions
What are the three basic processes that help us know the world?
The three basic processes are sensation, attention, and perception, which are often considered elements of cognition.
What is the difference between sensation and perception?
Sensation is the initial detection of stimuli by sensory receptors, while perception is the interpretation and organization of these sensations into meaningful experiences.
What are the main types of attention discussed in the chapter?
The chapter discusses selective attention, divided attention, and sustained attention.
What are perceptual constancies?
Perceptual constancies are the tendency to perceive objects as stable (e.g., in size, shape, colour) despite changes in the sensory information received.
What role do socio-cultural factors play in perception?
Socio-cultural factors can influence how we perceive the world, affecting our interpretations and expectations based on our background and environment.
What is the purpose of studying sensory, attentional, and perceptual processes?
Studying these processes helps us understand how we gather information, focus our awareness, and make sense of the world, which is fundamental to psychology and everyday life.
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NCERT Class 11 Psychology — Introduction to Psychology — Chapter 4 — Sensory, Attentional and Perceptual Processes. Verified by NCERT Help Editorial Team. Reviewed on 29 Jul 2026. Last updated 10 Aug 2026.