Retrieval Of Verbal Information Research Articles

Tetrahydrocannabinol (THC) impairs encoding but not retrieval of verbal information

IntroductionCannabis and agonists of the brain cannabinoid receptor (CB1R) produce acute memory impairments in humans. However, the extent to which cannabinoids impair the component processes of encoding and retrieval has not been established in humans. The objective of this analysis was to determine whether the administration of Δ9-Tetrahydrocannabinol (THC), the principal psychoactive constituent of cannabis, impairs encoding and/or retrieval of verbal information. Materials and methodsHealthy subjects were recruited from the community. Subjects were administered the Rey-Auditory Verbal Learning Test (RAVLT) either before administration of THC (experiment #1) (n=38) or while under the influence of THC (experiment #2) (n=57). Immediate and delayed recall on the RAVLT was compared. Subjects received intravenous THC, in a placebo-controlled, double-blind, randomized manner at doses known to produce behavioral and subjective effects consistent with cannabis intoxication. ResultsTotal immediate recall, short delayed recall, and long delayed recall were reduced in a statistically significant manner only when the RAVLT was administered to subjects while they were under the influence of THC (experiment #2) and not when the RAVLT was administered prior. ConclusionsTHC acutely interferes with encoding of verbal memory without interfering with retrieval. These data suggest that learning information prior to the use of cannabis or cannabinoids is not likely to disrupt recall of that information. Future studies will be necessary to determine whether THC impairs encoding of non-verbal information, to what extent THC impairs memory consolidation, and the role of other cannabinoids in the memory-impairing effects of cannabis. Clinical Trial Information:Cannabinoids, Neural Synchrony, and Information Processing (THC-Gamma)http://clinicaltrials.gov/ct2/show/study/NCT00708994NCT00708994Pharmacogenetics of Cannabinoid Responsehttp://clinicaltrials.gov/ct2/show/NCT00678730NCT00678730

Fit to last: Exploring the longevity of the survival processing effect.

Mounting evidence indicates that processing items for their survival value produces superior recall compared to a number of other well-known memory-enhancing techniques, and that this mnemonic advantage remains up to 48 hours after encoding (Raymaekers et al., 2014 ). However, little attention has been dedicated to the survival processing effect in location memory, which may represent a better test of adaptive memory than retrieval of verbal information. The current study aims to fill this gap by exploring the longevity of the survival processing effect with both word list (Experiment 1) and location-based (Experiment 2) stimuli. Participants rated target items using a single incidental encoding scenario, either Survival versus Pleasantness (word stimuli) or Survival versus Scavenger Hunt (location stimuli). They were then asked to complete a surprise recall task immediately after the ratings and a second recall task 96 hours later. The results demonstrated that, despite a general reduction in memory performance across time, the survival processing advantage was detected at both test times for both stimuli types. These findings provide further support for the survival processing effect and extend the observed effect duration for both word lists and location to 96 hours.

The Influence of Music on Prefrontal Cortex during Episodic Encoding and Retrieval of Verbal Information: A Multichannel fNIRS Study.

Music can be thought of as a complex stimulus able to enrich the encoding of an event thus boosting its subsequent retrieval. However, several findings suggest that music can also interfere with memory performance. A better understanding of the behavioral and neural processes involved can substantially improve knowledge and shed new light on the most efficient music-based interventions. Based on fNIRS studies on music, episodic encoding, and the dorsolateral prefrontal cortex (PFC), this work aims to extend previous findings by monitoring the entire lateral PFC during both encoding and retrieval of verbal material. Nineteen participants were asked to encode lists of words presented with either background music or silence and subsequently tested during a free recall task. Meanwhile, their PFC was monitored using a 48-channel fNIRS system. Behavioral results showed greater chunking of words under the music condition, suggesting the employment of associative strategies for items encoded with music. fNIRS results showed that music provided a less demanding way of modulating both episodic encoding and retrieval, with a general prefrontal decreased activity under the music versus silence condition. This suggests that music-related memory processes rely on specific neural mechanisms and that music can positively influence both episodic encoding and retrieval of verbal information.

What forgetting tells us about remembering: The influence of top–down control on hemispheric asymmetries in verbal memory

It has been suggested that left hemisphere (LH) advantages in verbal processing is due to superior top–down control of verbal information. It is not clear how top–down mechanisms affect the encoding and retrieval of verbal information from hemispheric memory and whether they only influence activation or also encompass the inhibition of verbal information. The directed forgetting method, in conjunction with divided visual field presentation, was used to examine the influence of top–down control mechanisms on hemispheric asymmetries in verbal memory. Participants were cued to remember or forget words. Cues were presented either simultaneously with targets or after a short delay. A recognition memory test using divided visual field presentation was then given. Response times (RTs) revealed effects of cue timing in the LH. With simultaneous cues, RTs were faster to “Remember” words compared to “Forget” words. With delayed cues, RTs for “Remember” and “Forget” words were equivalent. In the right hemisphere (RH), “Remember” words were consistently faster than “Forget” words, regardless of cue timing. These data provide evidence that top–down mechanisms influenced LH verbal memory retrieval more than RH verbal memory retrieval. Finally, there was little evidence to suggest the hemispheres differ in inhibitory processing.

Cerebellar-Parietal Connections Underpin Phonological Storage

Previous research has accumulated convincing evidence to show that the human cerebellum contributes to the short-term storage of verbal information, but its specific role in brain networks involved in phonological storage remains uncertain. In a randomized, crossover and sham-controlled design, we here combined transcranial direct current stimulation (tDCS), applied to the right cerebellum, with fMRI to investigate systematically the contribution of the human cerebellum to encoding, maintenance, and retrieval of verbal information. After anodal, but not cathodal, tDCS, we found a reduced item recognition capacity together with an attenuated neural signal from the right cerebellar lobule VIIb, specifically during the late encoding phase. Within this phase, tDCS furthermore affected task-associated functional connections between right cerebellar lobule VIIb and the posterior parietal cortex. These findings suggest that the right cerebellar lobule VIIb interacts with the posterior parietal cortex, specifically during the late stages of verbal encoding, when verbal information enters phonological storage.

Long-term memory: A review and meta-analysis of studies of declarative and procedural memory in specific language impairment.

This review examined the status of long-term memory systems in specific language impairment (SLI), in particular declarative memory and aspects of procedural memory. Studies included in the review were identified following a systematic search of the literature and findings combined using meta-analysis. This review showed individuals with SLI are poorer than age matched controls in the learning and retrieval of verbal information from the declarative memory. However, there is evidence to suggest that the problems with declarative learning and memory for verbal information in SLI might be due to difficulties with verbal working memory and language. The learning and retrieval of non-verbal information from declarative memory appears relatively intact. In relation to procedural learning and memory, evidence indicates poor implicit learning of verbal information. Findings pertaining to nonverbal information have been mixed. This review of the literature indicates there are now substantial grounds for suspecting that multiple memory systems may be implicated in the impairment.

Measurement of Recovery after Traumatic Brain Injury: A Cognitive-Neuropsychological Comparison of the WAIS-R with the Cognitive Assessment System (CAS) in a Single Case of Atypical Language Lateralization

A 20-year-old preferentially left-handed male suffered an extensive right, focal, medial, prefrontal hematoma and contusion with associated swelling, and an initially undetected progressive loss of consciousness following trauma to the forehead. Performance on the Cognitive Assessment System (CAS) at 1 and 6 months after traumatic brain injury was compared with performance on the WAIS-R at 6 months post-injury. The patient demonstrated significant residualized impairment on selected subtests of the CAS at 6 months post-injury (all ps < 0.05). The patient was also significantly impaired on the Information, Vocabulary, Arithmetic and Comprehension verbal subtests of the WAIS-R. The magnitude of these WAIS-R subtest discrepancies occurred with a low base rate (< 1%) in the WAIS-R standardization sample. In addition there was a significant VIQ versus PIQ discrepancy favouring PIQ of a magnitude occurring in less than 5% of the WAIS-R standardization sample. These findings could not be explained on the basis of any prior learning disability, poor educational opportunities, medication use, response bias, confabulation, or low level of general ability. The low scores on the verbal subtests of the WAIS-R in conjunction with the impairment on the CAS subtests are highly suggestive of lasting frontal-executive dysfunction in this patient. Incidental findings of persisting anomia, impaired processing of proverbs, acalculia, and fluctuating verbal attention, as well as impaired retrieval of verbal information in the context of intact PIQ and superior constructional praxis suggest some degree of bilateral representation of linguistic functions. The differential assessment of cognitive domains by these two instruments as well as theoretical concordance in the pattern of results is also addressed.

Differential effects of lead exposure on components of verbal memory

Aims: To determine if verbal learning and memory requiring acquisition and retention of information is differentially affected by lead exposure. Methods: The Rey Auditory Verbal Learning Test (RAVLT), a test...

GENETIC AND ENVIRONMENTAL INFLUENCES ON THE ORGANISATION OF SEMANTIC MEMORY IN THE BRAIN:IS “LIVING THINGS” AN INNATE CATEGORY?

The organisation of semantic memory into separately lesionable or imageable components must be determined by some combination of genetic and environmental factors. Little is known about the relative contributions of these two factors in establishing the functional architecture of semantic memory. By assessing the semantic memory impairment of an individual who sustained brain damage as a newborn, it is possible to place an upper bound on the contribution of post-natal experience. The present case study demonstrates a profound and enduring impairment in knowledge of “living things” following posterior cerebral artery infarctions at approximately 1 day of age. The design of the two experiments reported here allows us to characterise the subject's semantic memory impairment in terms of its scope and selectivity. The impairment affects both the naming of pictures of living things and the retrieval of verbal information about living things. It cannot be accounted for by differences in the difficulty of retrieving knowledge of living and nonliving things, as the living and nonliving items were equated for difficulty in each experiment. When visual and nonvisual information were queried separately for living and nonliving things, the impairment was manifest for both kinds of information about living things, but for neither kind of information about nonliving things. Because this impairment resulted from brain damage sustained too early for experience to have contributed to the organisation of semantic memory, this case study supports a genetic basis for the living-nonliving distinction in semantic memory.

Memory Abilities of Reading-Disabled Children with VIQ-PIQ Differences

Associations between VIQ and verbal memory and between PIQ and nonverbal memory have been found in neurologically impaired adults. This study examined the assumption that similar associations will hold for children with reading disabilities (RD) who demonstrate lower VIQ relative to PIQ and the converse. The Verbal and Nonverbal Selective Reminding Tests were administered to children aged 10 to 12 years. Thirteen RD children with VIQ &lt; PIQ 14 RD children with PIQ &lt; VIQ and 14 controls served as subjects. Contrary to predictions, memory functions were not found to parallel intellectual functions. The children with lower PIQ displayed poorer storage and retrieval of verbal information along with poorer retrieval of nonverbal information. These results suggest that children with reading disabilities who obtain relatively lower PIQ might be expected to experience more memory problems than children with lower VIQ regardless of modality of input.

Drawing Maps from Text: A Test of Conjoint Retention

Abstract Undergraduates read a narrative text in which target features were elaborated in terms of spatial, descriptive, or both spatial and descriptive text referents. As they studied the passage, groups of subjects were instructed to draw one of three types of maps, based upon text content. The subjects drew maps with accurate geographical features, drew personal representations designed to help them remember the narrative, or drew target map features in columns. The subjects took an immediate and a delayed test covering both feature-related and nonrelated text material and, following the delayed test, attempted to reconstruct their original version of the map. Creating personal maps resulted in better text recall and yielded the highest conditional probabilities of recall for a feature-related item, given that the subjects also remembered the map feature. These results support the conjoint retention hypothesis, which emphasizes the retrieval of verbal information from jointly stored verbal-spatial memory.

Multiple memory deficits in patients with multiple sclerosis. Exploring the working memory system.

Some patients with multiple sclerosis (MS) demonstrate impaired memory. A group of 16 patients with MS who were mildly to moderately affected (Kurtzke Expanded Disability Status Scale Score = 3.8) were studied, and they were compared with a matched control group on tests of "working memory." The working memory system was explored by evaluating the amount of information that can temporarily be held in a buffer system during encoding. Results indicated that patients with MS have difficulty in processing information at the level of a hypothesized articulatory loop in working memory. This deficit was correlated with their retrieval of verbal information from long-term memory, as well as how accurately they processed verbal information presented at a rapid rate. There was no significant relationship between ratings of MS severity or number of plaques visualized on magnetic resonance imaging scans and the degree of working memory deficit.

A Study of the Relationship Between Speed of Retrieval of Verbal Information and Patterns of Oral Reading Errors

Do children with learning problems, who vary in speed of verbal retrieval, tend to use reading strategies differerzt from those of normal readers? This study explored one aspect of that question by examining the relutionship between speed of retrieval of verbal information and patterns of oral reading responses in a population of 91 children with learning problems in grades 2 through 5. A Naming Task required the rapid naming of colors, numbers, upper and lower case letters, and common objects. An oral reading selection was analyzed using categories from the Reading Miscue Inventory. The findings suggest that rapid and slow retrievers develop oral reading strategies similar to normal readers, and that children with learning problems can and do use graphophonic, svtuaotic, and semantic cues. Implications for the re-evaluation of special programs designed for children with learning problems are discussed.

Improving retention in alcoholic Korsakoff patients.

Use of visual images facilitated the storage and retrieval of verbal information, use of verbal cues facilitated the retention of nonverbal materials, and semantic analysis enhanced recognition of verbal material by alcoholic Korsakoff patients.