Related Experiment Video
Updated: Jul 16, 2026
06:48
Lexical Decision Task for Studying Written Word Recognition in Adults with and without Dementia or Mild Cognitive Impairment
Published on: June 25, 2019
Deficits in irregular past-tense verb morphology associated with degraded semantic knowledge
K Patterson1, M A Lambon Ralph, J R Hodges
1MRC Cognition and Brain Sciences Unit, 15 Chaucer Road, Cambridge CB2 2EF, UK. karalyn.patterson@mrc-cbu.cam.ac.uk
Neuropsychologia
|April 20, 2001
Summary
Patients with semantic dementia show normal regular past-tense verb skills but impaired irregular past-tense verb generation, linked to semantic knowledge loss.
Area of Science:
- Neuroscience
- Psycholinguistics
- Cognitive Science
Background:
- Traditional models propose separate mechanisms for regular (rule-based) and irregular (lexical) past-tense verb formation.
- An alternative parallel-distributed processing model suggests a single complex system handles all verb tenses.
- The role of semantic knowledge in verb-tense processing, particularly for irregular forms, remains under-explored.
Observation:
- This study investigated past-tense verb abilities in 11 patients with semantic dementia, a condition marked by degraded semantic knowledge.
- Patients exhibited preserved ability in generating and recognizing regular and novel past-tense verbs.
- A significant deficit was observed in the generation of irregular past-tense verbs, which was modulated by verb frequency.
Findings:
- Semantic dementia patients demonstrated intact regular past-tense formation but impaired irregular past-tense formation.
- The severity of irregular past-tense impairment correlated significantly with the degree of semantic comprehension deficits.
- Error patterns in irregular verb generation provided further support for the link between semantics and irregular past-tense processing.
Implications:
- Results support theories linking semantic knowledge to the processing of irregular past-tense verbs.
- Findings challenge purely rule-based or lexical accounts, favoring models that integrate semantic information.
- This research offers insights into language processing deficits in neurodegenerative conditions like semantic dementia.
Related Concept Videos
01:26Higher Mental Functions of Brain: Learning and Memory
Memory is one of the most vital higher mental functions of the brain. Memory is closely related to learning because it enables us to retain information and experiences from our past to use them in our present life. It also helps us to remember facts, events, and skills, such as riding a bike or swimming. There are two types of memory — declarative memory, which involves memorizing facts or events, and procedural memory, which enables us to remember how to do something like writing or playing an...
01:10Higher Mental Functions of the Brain: Language
Language is a system of communication that allows the expression of thoughts, ideas, and feelings. The brain processes language in both hemispheres.
Language formation and comprehension take place in the dominant hemisphere. The dominant hemisphere is responsible for understanding the meaning of spoken, written, or sign language, as well as the ability to communicate. For most people, the left hemisphere is the dominant one. The right hemisphere, then, gives tone and emotional context to the...
Language formation and comprehension take place in the dominant hemisphere. The dominant hemisphere is responsible for understanding the meaning of spoken, written, or sign language, as well as the ability to communicate. For most people, the left hemisphere is the dominant one. The right hemisphere, then, gives tone and emotional context to the...
01:21Forgetting
Forgetting is an intrinsic aspect of human memory, characterized by the gradual loss or inaccessibility of information over time. Hermann Ebbinghaus, a pioneering psychologist, extensively studied this phenomenon and formulated the forgetting curve. This curve illustrates that memory loss occurs rapidly immediately after learning and then decelerates over time. Several mechanisms contribute to forgetting, including encoding failure, storage decay, retrieval failure, and interference.
Encoding...
Encoding...
01:16Interference and Decay
Forgetting is a complex cognitive phenomenon influenced by several factors, among which interference and decay are particularly prominent. These processes explain why individuals often struggle to retrieve specific information from memory, leading to lapses in recall that can be observed in everyday situations.
Interference occurs when competing memories hinder the retrieval of particular information. It can be classified into two types: proactive and retroactive interference. Proactive...
Interference occurs when competing memories hinder the retrieval of particular information. It can be classified into two types: proactive and retroactive interference. Proactive...
01:10Tip-of-the-Tongue Phenomenon
The tip-of-the-tongue (TOT) phenomenon is a cognitive experience characterized by a temporary inability to retrieve specific information from memory despite having a strong feeling of knowing the information. Although individuals cannot access the target word or detail, they frequently recall related elements, such as its initial letter, syllable count, or context. This partial retrieval often causes frustration, as one might recognize a familiar face or know that a name starts with a specific...
01:13Amnesia
Amnesia is a condition marked by long-term memory loss, which impairs the ability to recall past events or create new memories.
The severity and duration of memory loss vary depending on the type and underlying cause. Amnesia is classified into two main types: retrograde and anterograde.
Retrograde amnesia is marked by the loss of memories formed before the onset of the condition. Patients may recall distant past events but often forget those occurring shortly before the incident.
Anterograde...
The severity and duration of memory loss vary depending on the type and underlying cause. Amnesia is classified into two main types: retrograde and anterograde.
Retrograde amnesia is marked by the loss of memories formed before the onset of the condition. Patients may recall distant past events but often forget those occurring shortly before the incident.
Anterograde...