COVCOG: Immediate and long-term cognitive improvement after cognitive versus emotion management psychoeducation programs - a randomized trial in covid patients with neuropsychological difficulties.

BACKGROUND: Cognitive difficulties are a frequent complaint in long COVID and persist for more than a year post- infection. There is a lack of evidence-based data on effective intervention strategies. Non-pharmacological intervention programs that are used with other neurological populations have not yet been the subject of controlled trials. COVCOG is a multicentric, randomized trial comparing cognitive intervention and a cognitive-behavioural counselling. METHODS/DESIGN: Patients with long covid are selected and recruited at least three months post-infection. Patients are randomised in a 1:1 ratio into the cognitive (neuropsychological psychoeducation) and affective (emotion management with cognitive-behavioural counselling) intervention arms. The inclusion of 130 patients is planned. The cognitive intervention includes psycho-educational modules on fatigue and sleep, attention and working memory, executive functions and long-term memory. The affective intervention includes modules on emotion recognition and communication, uncertainty management and behavioral activation. The main objective is to reduce cognitive complaints 2 months after the intervention. A Follow-up is also planned at 8 months. DISCUSSION: Given the long-term effects of Covid on cognition and the negative effects of cognitive impairment on quality of life and social participation, it is important to determine whether low-dose, non-pharmacological interventions can be effective. The trial will determine which of the usual types of intervention is the most effective. TRIAL REGISTRATION: Clinicaltrials.gov Number: NCT05167266 (21/12/ 2021).

Decreased Alpha Peak Frequency Is Linked to Episodic Memory Impairment in Pathological Aging.

The Free and Cued Selective Reminding Test (FCSRT) is a largely validated neuropsychological test for the identification of amnestic syndrome from the early stage of Alzheimer's disease (AD). Previous electrophysiological data suggested a slowing down of the alpha rhythm in the AD-continuum as well as a key role of this rhythmic brain activity for episodic memory processes. This study therefore investigates the link between alpha brain activity and alterations in episodic memory as assessed by the FCSRT. For that purpose, 37 patients with altered FCSRT performance underwent a comprehensive neuropsychological assessment, supplemented by 18F-fluorodeoxyglucose positron emission tomography/structural magnetic resonance imaging (18FDG-PET/MR), and 10 min of resting-state magnetoencephalography (MEG). The individual alpha peak frequency (APF) in MEG resting-state data was positively correlated with patients' encoding efficiency as well as with the efficacy of semantic cues in facilitating patients' retrieval of previous stored word. The APF also correlated positively with patients' hippocampal volume and their regional glucose consumption in the posterior cingulate cortex. Overall, this study demonstrates that alterations in the ability to learn and store new information for a relatively short-term period are related to a slowing down of alpha rhythmic activity, possibly due to altered interactions in the extended mnemonic system. As such, a decreased APF may be considered as an electrophysiological correlate of short-term episodic memory dysfunction accompanying pathological aging.

High rate of errors in pillbox filling by cognitively healthy elderly people.

An appropriate medication management depends on executive system integrity, which can be affected by aging. Previous studies showed that seniors commit frequent errors when having to fill in a pillbox. Nevertheless, to the best of our knowledge, no study has really considered the absence of cognitive disorders in the studied sample. The present study aimed to investigate pillbox filling in cognitively healthy elderly (specially focusing on executive system preservation) for whom no cognitive deterioration neither any depressive episode had occurred during a one year period. The filling task has been completed using a weekly pillbox and eight fictitious drugs. The selection of the 27 seniors aged from 71 to 90 years has been based on their results to neuropsychological tests (Trail making test, Stroop Victoria, Tower of London, Montreal cognitive assessment) and a depression assessment scale (Short geriatric depression scale). Results showed that 67% of the participants committed at least one error when filling the pillbox and 56% at least 3. The maximal number of errors was 38. Further, the errors analysis showed that 85% of the errors had been repeated (e.g. reproduced on several days). Finally, the more complex the drug prescriptions are, the higher the error rate is. No other variable (age, gender, level education, habit of filling a pillbox) had any effect on the number of errors. So, the pillbox filing task can be considered as a complex task associated with a high risk of errors. Moreover, the absence of cognitive disorders is not a success factor to the task. A prospect for the future should be to try to limit the error rate by developing, for instance, an external support helping to the filling of the pillbox and a learning process for the use of this support.

Cognitive Improvement of Attention and Inhibition in the Late Afternoon in Children With Attention-Deficit Hyperactivity Disorder (ADHD) Treated With Osmotic-Release Oral System Methylphenidate.

Long-acting medications have been developed and approved for use in the treatment of attention-deficit hyperactivity disorder (ADHD). These compounds are intended to optimize and maintain symptoms control throughout the day. We tested prolonged effects of osmotic-release oral system methylphenidate on both attention and inhibition, in the late afternoon. A double-blind, randomized, placebo-controlled study was conducted in 36 boys (7-12 years) with ADHD and 40 typically developing children. The ADHD children received an individualized dose of placebo or osmotic-release oral system methylphenidate. They were tested about 8 hours after taking with 2 continuous performance tests (continuous performance test-X [CPT-X] and continuous performance test-AX [CPT-AX]) and a counting Stroop. A positive effect of osmotic-release oral system methylphenidate was present in CPT-AX with faster and less variable reaction times under osmotic-release oral system methylphenidate than under placebo, and no difference with typically developing children. In the counting Stroop, we found a decreased interference with osmotic-release oral system methylphenidate but no difference between children with ADHD under placebo and typically developing children.

Can amnesic patients learn without awareness? New evidence comparing deterministic and probabilistic sequence learning.

Can associative learning take place without awareness? We explore this issue in a sequence learning paradigm with amnesic and control participants, who were simply asked to react to one of four possible stimuli on each trial. Unknown to them, successive stimuli occurred in a sequence. We manipulated the extent to which stimuli followed the sequence in a deterministic manner (noiseless condition) or only probabilistically so (noisy condition). Through this paradigm, we aimed at addressing two central issues: first, we asked whether sequence learning takes place in either condition with amnesic patients. Second, we asked whether this learning takes place without awareness. To answer this second question, participants were asked to perform a subsequent sequence generation task under inclusion and exclusion conditions, as well as a recognition task. Reaction times results show that amnesic patients learned the sequence only in the deterministic condition. However, they failed to be able to reproduce the sequence in the generation task. In contrast, we found learning for both sequence structures in control participants, but only control participants exposed to a deterministic sequence were successful in performing the generation task, thus suggesting that the acquired knowledge can be used consciously in this condition. Neither amnesic nor control participants showed correct old/new judgments in the recognition task. The results strengthen the claim that implicit learning is at least partly spared in amnesia, and the role of contextual information available for learning is discussed.

A Case Study of Visual Agnosia without Perceptual Processing or Structural Descriptions Impairment.

We report a new case of visual associative agnosia. Our patient (DJ) was impaired in several tasks assessing visual processing of real objects, colour pictures, and line drawings. The deficit was present both with naming and gesturing responses. Object processing in other modalities (verbal, auditory nonverbal, and tactile) was intact. Semantic processing was impaired in the visual but not in the verbal modality. Picture-word matching was better than single picture identification. DJ's visual perceptual processing, was intact in several tasks such as visual attributes discrimination, shape discrimination, illusory contours perception, segmentation, embedded figures processing and matching objects under different viewpoints. Most importantly, we show that there was no impairment of stored structural descriptions and that the patient was able to build new visual representations. These results are considered in the context of Farah's (1990, 1991) proposals about visual associative agnosia.

Is the attentional blink effect located in short-term memory?

The attentional blink (AB) effect is characterized by a failure to detect a second target following the identification of a previous target in a RSVP stream. This effect has been attributed to capacity limitations at a central level of visual information processes. Postperceptual models suppose that the AB locus is located in short-term memory. To test this hypothesis, we investigated the influence of a short-term memory deficit on the AB effect in a patient with such a deficit. The three main results of this study are (1) the persistence of an AB effect, (2) a large number of T1 missed identifications and (3) a T2 detection deficit for a specific delay (367 ms). These results indicate that a short-term memory deficit disrupts the processing of each target (T1 and T2) but does not product an abolition of the AB effect.

The fur of the crocodile and the mooing sheep: A study of a patient with a category-specific impairment for biological things.

We report a single case study of a brain-damaged patient, ER, who showed a remarkably consistent category-specific deficit for living things. His impairment was observed across tasks (naming, definition, matching, drawing from memory, questionnaires), input modalities (visual, verbal, nonverbal auditory), and output modalities (verbal vs. pointing or visual matching responses) as well as for different types of knowledge. Although visual knowledge of living things was severely affected, his category-specific impairment in nonverbal sound recognition is inconsistent with models of category-specific deficits based on pre-semantic visual descriptions. ER's deficit cannot fully be explained by item typicality, word frequency, visual complexity, homomorphy, age of acquisition, value to perceiver, or modality of transaction. Furthermore, in ER, contextual cues were even slightly detrimental for the recognition of animals. ER's naming and recognition errors were constrained by the categorical structure of the knowledge base: In most cases they respected both the second- and first-order superordinates. In particular, ER's knowledge of shared categorical properties related to biological function was almost spared. This result is compatible with the idea that, for living things, shared functional properties and shared perceptual properties are strongly correlated. Feature-based models assuming perceptual vs. functional semantic components cannot account for ER's deficit, since for living things he was impaired on both kinds of features to a similar extent. ER's behaviour is quite consistent with the notion that conceptual knowledge is organised categorically in the brain, with one or several specialised subsystems for biologically related entities.