CBSE Class 11 Psychology Chapter 7: Human Memory NCERT Solutions

Solution: Memory is understood as a process involving three interconnected stages: encoding, storage, and retrieval.

Encoding: This is the initial stage where incoming information is registered and processed so that it can be used by the memory system. During encoding, information is received, and some form of meaning is derived from it.

Storage: This is the second stage, crucial for retaining information over time. Storage refers to the process by which encoded information is preserved and held for later use.

Retrieval: This is the third and final stage. Information stored in memory can only be utilized when it is successfully brought back into conscious awareness. Retrieval involves accessing and bringing forth the stored information to perform cognitive tasks.

Solution: The Atkinson and Shiffrin model, also known as the stage model of memory, proposes that information is processed through three distinct, sequentially linked memory systems: sensory memory, short-term memory (STM), and long-term memory (LTM).

Sensory Memory: This system receives and briefly preserves sensory stimuli. It has a large capacity but a very short duration, typically less than a second. It holds a fleeting impression of sensory input.

Short-Term Memory (STM): STM holds a limited amount of recently perceived information for a brief period, usually less than 30 seconds. Information in STM is primarily encoded acoustically. Its capacity is limited.

Long-Term Memory (LTM): LTM serves as a more permanent store for memories. Information is encoded semantically in this stage, and its storage capacity is considered unlimited. Information from STM can be transferred to LTM through processes like rehearsal.

These memory systems differ in how they process information, their capacity (how much they can hold), and their duration (how long they can hold it).

Solution: Maintenance rehearsals and elaborative rehearsals are two distinct control processes used in memory, primarily differing in their depth of processing and effect on memory retention.

Maintenance Rehearsals: These are simple repetitions of information, either silently or vocally, used to keep information active in short-term memory for as long as needed. However, this type of rehearsal does not lead to deep understanding or long-term retention; the information is typically lost once the repetitions stop.

Elaborative Rehearsals: This process involves connecting new information to existing knowledge already stored in long-term memory. It requires deeper cognitive effort, such as analyzing the information, assigning meaning, and forming associations or mental images. For example, remembering the word "humanity" is easier if one already understands concepts like "compassion" and "benevolence." Elaborative rehearsals are more effective for transferring information into long-term memory.

Solution: Declarative and procedural memories are two major types of long-term memory, distinguished by the nature of the information they store.

Declarative Memory: This type of memory pertains to facts, concepts, and events that can be consciously recalled and verbally described. Examples include knowing that a bicycle has two wheels, the date of India's independence, or the definition of a word. It is memory for 'what'.

Procedural Memory: This type of memory relates to the skills and procedures required to perform various tasks. It is often referred to as 'knowing how' to do something, such as riding a bike, typing, or playing a musical instrument. These memories are typically demonstrated through performance rather than verbal recall.