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Andrew E Budson

Publications and source records attributed to Andrew E Budson.

30 records · Page 2Linked to original sources
PubMed2004

Age-related differences in novelty and target processing among cognitively high performing adults.

Previous research on age-related changes in ERP components in response to novel and target stimuli has not carefully controlled for differences in level of cognitive status between age groups, which may have contributed to the common findings of increased P3 latency, decreased P3 amplitude, and altered P3 scalp distribution. Here, cognitively high-performing (top third based on published norms) old, middle-aged, and young adults matched for IQ, education, and gender participated in a novelty oddball paradigm. There were no age-associated differences in P3 latency. Older adults had a larger, more anteriorly distributed P3 amplitude to all stimulus types, even repetitive standards, suggesting they may rely on increased resources and effortful frontal activity to successfully process any kind of visual stimulus. However, after controlling for this non-specific age-related processing difference, the amplitude and scalp distribution of the P3 component to novel and target stimuli were comparable across age groups, indicating that for cognitively high functioning elders there may be no age-related differences specific to the processing of novel and target events as indexed by the P3 component.

Adolescent↗
PubMed2004

An electrophysiological investigation of the relationship between conceptual fluency and familiarity.

Brain potentials associated with the manipulation of conceptual fluency in a recognition memory paradigm were recorded. Enhanced fluency was associated with attenuation of the N400 and an increased rate of subjects' endorsing both studied and non-studied items as having been studied ("old" responses) in the recognition test. Differences were also found in latencies previously associated with post-retrieval processing, such that in the setting of enhanced fluency (1) non-studied items were associated with a positive wave from 800 to 1600 ms and (2) items endorsed as "new" were more positive than those endorsed as "old" from 1200 to 1600 ms. The effects on the N400 may be related to the impact of fluency on familiarity, whereas later processing may be involved in the attribution of fluency to prior experience.

Adolescent↗
PubMed2004

Use of IQ-adjusted norms to predict progressive cognitive decline in highly intelligent older individuals.

Identifying high-functioning older individuals in preclinical phases of Alzheimer's disease (AD) may require more sensitive methods than the standard approach. The authors explored the utility of adjusting for premorbid intelligence to predict progressive cognitive decline or Mild Cognitive Impairment (MCI) in 42 highly intelligent older individuals. When scores were adjusted for baseline IQ, 9 participants had executive impairments, 11 had memory impairments, and 22 scored in the normal range. None were impaired according to standard age norms. Three and a half years later, 9 participants with IQ-adjusted memory impairment declined in naming, visuospatial functioning, and memory; 6 convened to MCI. Three participants with normal memory declined. Implications for using IQ-adjusted norms to predict preclinical AD are discussed.

Aged↗
PubMed2004

Memory and emotions for the september 11, 2001, terrorist attacks in patients with Alzheimer's disease, patients with mild cognitive impairment, and healthy older adults.

National traumatic events can produce extremely vivid memories. Using a questionnaire administered during telephone interviews, the authors investigated emotional responses to, and memory for. the September 11, 2001, terrorist attacks in patients with Alzheimer's disease (AD), patients with mild cognitive impairment (MCI), and healthy older adults in the initial weeks following the event and again 3-4 months later. There were several notable findings. First, patients with AD showed less memory than patients with MCI and older adults. Second, patients with AD, but not patients with MCI or older adults, appeared to retain more memory for personal versus factual information. Third, patients with AD and older adults did not differ in the intensity of their reported emotional responses to the attacks, whereas patients with MCI reported relatively less intense emotional responses. Last, distortions of memory for personal information were frequent for all participants but were more common in patients with AD.

Aged↗
PubMed2004

Associative recognition in Alzheimer's disease: evidence for impaired recall-to-reject.

Patients with mild Alzheimer's disease (AD) were compared with age-matched control subjects on an associative recognition task. Subjects studied pairs of unrelated words and were later asked to distinguish between these same studied pairs (intact) and new pairs that contained either rearranged studied words (rearranged) or non-studied words (non-studied). Studied pairs were presented either once or 3 times. Repetition increased hits to intact pairs in both groups, but repetition increased false alarms to rearranged pairs only in patients. This latter pattern indicates that repetition increased familiarity of the rearranged pairs, but only the control subjects were able to counter this familiarity by recalling the originally studied pairs (a recall-to-reject process). AD impaired this recall-to-reject process, leading to more familiarity based false alarms. These data support the idea that recollection-based monitoring processes are impaired in mild AD.

Aged↗
PubMed2003

Late frontal brain potentials distinguish true and false recognition.

Brain potentials associated with true and false recognition were recorded using a paradigm consisting of categorized color photographs. Two ERP components were identified. A parietal component was most positive for both true and false recognition, less positive for rejection of lures, and least positive for rejection of novel items. A later frontal component was more positive for false recognition, rejection of lures, and misses than for true recognition and rejection of novel items. The authors suggest that the parietal component may reflect the extent to which test items engender recollection of the gist representation of the study list, while the late frontal component may reflect the engagement of effortful post-retrieval processes.

Adult↗
PubMed2003

Semantic versus phonological false recognition in aging and Alzheimer's disease.

Patients with Alzheimer's disease (AD) have been found to exhibit lower levels of false recognition of semantic associates compared with healthy older adults. Because these patients may show impaired performance of episodic and semantic memory tasks, this finding could be explained by deficits in episodic memory, semantic memory, or both. The authors adapted a paradigm for comparison of semantic versus phonological false recognition. They found that: (a) patients with AD exhibited lower levels of corrected false recognition of semantic, phonological, and hybrid (mixed semantic and phonological) lists than older adults, and (b) patients with AD showed very similar levels of false recognition for all list types. These results suggest that only episodic memory deficits are necessary to explain the lower level of false recognition of semantic associates observed in patients with AD when compared to older adults. Additionally, (c) older adults showed greater levels of semantic, phonological, and hybrid false recognition than younger adults, extending previous false recognition research of semantically related words and categorized colored photographs to phonologically related words.

Aged↗
PubMed2003

False recognition in Alzheimer disease: evidence from categorized pictures.

OBJECTIVES: To better understand memory distortions and false recognition in patients with Alzheimer disease (AD), using a paradigm of categorized color photographs. BACKGROUND: Previous research has found that patients with AD and older adults showed similar levels of uncorrected false recognition of semantic associates and of perceptually related novel objects. In contrast to these results, using a paradigm in which semantically related words were accompanied by black and white line drawings, it was found that patients with AD showed a trend toward higher levels of uncorrected false recognition compared with older adults. METHODS: To explore this trend, 24 patients with AD and 24 older adults matched for age, education, and gender were examined using a false recognition paradigm consisting of categorized color photographs (e.g., flowers, motorcycles, cats). RESULTS: Compared with older adults, patients with AD showed higher levels of uncorrected false recognition, but lower levels of corrected false recognition and lower levels of item-specific recollection. CONCLUSIONS: The authors suggest that these results may be attributable to the poor ability of patients with AD to acquire both gist and item-specific information as well as these patients' inherent frontal lobe dysfunction leading to difficulty inhibiting responses on the basis of familiarity alone.

Aged↗
PubMed2003

Increased T cell reactivity to amyloid beta protein in older humans and patients with Alzheimer disease.

Alzheimer disease (AD) is characterized by the progressive deposition of the 42-residue amyloid beta protein (Abeta) in brain regions serving memory and cognition. In animal models of AD, immunization with Abeta results in the clearance of Abeta deposits from the brain. However, a trial of vaccination with synthetic human Abeta1-42 in AD resulted in the development of meningoencephalitis in some patients. We measured cellular immune responses to Abeta in middle-aged and elderly healthy subjects and in patients with AD. A significantly higher proportion of healthy elderly subjects and patients with AD had strong Abeta-reactive T cell responses than occurred in middle-aged adults. The immunodominant Abeta epitopes in humans resided in amino acids 16-33. Epitope mapping enabled the identification of MHC/T cell receptor (TCR) contact residues. The occurrence of intrinsic T cell reactivity to the self-antigen Abeta in humans has implications for the design of Abeta vaccines, may itself be linked to AD susceptibility and course, and appears to be associated with the aging process.

Adult↗
PubMed2002

False recognition of pictures versus words in Alzheimer's disease: the distinctiveness heuristic.

False recognition of semantic associates can be reduced when older adults also study pictures representing each associate. D. L. Schacter, L. Israel, and C. Racine (1999) attributed this reduction to the operation of a distinctiveness heuristic: a response mode in which participants demand access to detailed recollections to support a positive recognition decision. The authors examined patients with probable Alzheimer's disease (AD) and older adults with this paradigm. Half of the participants studied pictures and auditory words; the other half studied visual and auditory words. Older adults who studied pictures were able to reduce their false alarms compared with those who studied words only. AD patients who studied pictures were unable to reduce their false alarms compared with those who studied words only and, in fact, exhibited trends toward greater false recognition. Implications for understanding semantic memory in AD patients are discussed.

Aged↗
PubMedDate not supplied

Use of a false recognition paradigm in an Alzheimer's disease clinical trial: a pilot study.

We report the first use of a false recognition memory test in a clinical trial of patients with Alzheimer's disease (AD). Tests of false recognition allow measurement of two components of memory: the specific details of a prior encounter with a particular item (item-specific recollection) and the general meaning, idea, or gist conveyed by a collection of items (gist memory). We used a false recognition paradigm with categorized pictures to study the effects of an experimental medication in patients with AD. Because medications to treat AD may preferentially improve gist memory or item-specific recollection, use of this type of paradigm may improve sensitivity for detection of drug effects more than standard memory tests.

Aged↗