Cognitive and Behavioral Neurology最新文献

Sensory impairments such as age-related hearing loss and poor eyesight have been associated with a negative impact on cognitive screening test scores. Many researchers use cognitive tests and consider factors such as vision and cardiac issues but do not account for hearing loss. We reviewed published literature in the field of gerontology to determine if hearing loss was considered in human subjects research that involved the administration of a cognitive battery or screening test. We present evidence for the need to consider hearing loss when administering cognitive screening tests, as well as recommendations for practitioners and researchers.

Background: Alzheimer disease dementia may be preceded by cognitive stages during which behavioral and psychological changes can occur. More precisely, behavioral symptoms may be observed during the subjective cognitive decline (SCD) or the mild cognitive impairment (MCI) stages; these symptoms can be measured using the Mild Behavioral Impairment Checklist (MBI-C).

Objective: To validate the French-Quebec version of the MBI-C in individuals ages 60-85 years.

Method: The sample included 60 participants (20 MCI, 20 SCD, 20 cognitively healthy) and their informants. To assess the discriminant validity of the MBI-C, a Kruskal-Wallis analysis with a multiple comparisons test was performed on the MBI-C Total score. To determine convergent validity, Spearman correlations were calculated between the MBI-C subscales and a set of validation tools. Finally, test-retest reliability was assessed with Spearman correlations of MBI-C scores between two test sessions.

Results: All of the analyses indicated satisfactory psychometric properties for the French-Quebec version of the MBI-C.

Conclusion: This validation study reveals that the MBI-C can be used successfully in dementia risk assessments. From now on, the use of a validated MBI-C will be possible in the French-Quebec population.

Background: Emotional distress can lead to suicidal ideation and potentially suicide completion, yet there is very little literature on suicidal ideation in individuals with a diagnosis of neurofibromatosis (NF; NF1, NF2, and schwannomatosis).

Objective: To examine the baseline occurrence, severity, and clinical correlates of suicidal ideation in adults with NF.

Method: Individuals with NF (N = 220) completed assessments measuring depression (Patient Health Questionnaire-9), anxiety (Generalized Anxiety Disorder-7), perceived stress (Perceived Stress Scale-10), pain (Graded Chronic Pain Scale and PROMIS Pain Interference Short Form 8a), and general quality of life (World Health Organization Quality of Life-Brief version) before beginning a two-arm, single-blind randomized control trial of a live-video mind-body program for stress management and resiliency.

Results: Nineteen percent (n = 42) of the individuals experienced suicidal ideation (ie, >0; ideation present several days or greater). More individuals with NF2 experienced suicidal ideation compared with those with NF1 or schwannomatosis. All of the clinical variables except pain intensity were significantly correlated ( P < 0.01) with greater suicidal ideation. Suicidal ideation in individuals with NF was comparable to or higher than that in other medical populations (eg, cancer, dermatological, neurologic). Depression and poor psychological quality of life significantly increased the risk for suicidal ideation.

Conclusion: Suicidal ideation was relatively prevalent in individuals with NF seeking participation in a mind-body randomized controlled trial. NF clinicians should be prepared to discuss these concerns and provide resources when suicidal ideation is present.

Clinical trial registration: ClinicalTrials.gov (Identifier NCT03406208).

Consciouness is a phenomenon that has eluded explanation by generations of physicians and scientists. Many discussions, experiments, and theories about consciousness have been published, but none has adequately explained the phenomenon. In the previous issue, Budson and colleagues (2022) present a theory of consciousness based on explicit memory processes, with consciousness developing in the context of memory function. In the authors' view, consciousness accompanying other cortical processes such as language or visual-spatial function developed only later in evolution. The evidence presented for this evolutionary sequence, however, is very limited. Furthermore, no discussion is directed toward the theory that consciousness involves the intersection between external perceptions and internal bodily states. The authors also develop the concept that most of our actions, and even our personality, are conscious only after the fact; immediate decisions are taken by the unconscious mind-the "horse" rather than the "rider." There is empirical evidence that rapid decisions and responses occur before they become conscious. However, Budson and colleagues (2022) extend the concept of unconscious decision-making to virtually all actions; in so doing, not only do they minimize the phenomenon of self-conscious awareness, but their theory has disturbing ethical implications for personal responsibility, criminal law, free will, and personality.

In the previous issue, Budson, Richman, and Kensinger (2022) put forth the intriguing proposal that consciousness may have evolved from the episodic memory system. In addition to providing a possible evolutionary trajectory for consciousness, I believe that viewing consciousness as an extension of memory in this way is particularly useful for understanding some of the puzzling temporal complexities that are inherent to consciousness. For example, due to neural transmission delays, our conscious experience must necessarily lag the outside world, which creates a paradox for both conscious perception (Do we see the past, rather than the present?) and action (How can we make rapid decisions if it takes so long to become conscious of something?). These paradoxes can be elegantly solved by treating consciousness as a memory system. Finally, the proposal put forth by Budson and colleagues (2022) aligns with the emerging perspective that consciousness, like memory, represents a narrative time line of events rather than any single instant. However, I believe that this conceptualization can be further extended to include not only the past, but also the future. In this way, consciousness can be provocatively viewed as the remembered past, present, and future.

We suggest that there is confusion between why consciousness developed and what additional functions, through continued evolution, it has co-opted. Consider episodic memory. If we believe that episodic memory evolved solely to accurately represent past events, it seems like a terrible system-prone to forgetting and false memories. However, if we believe that episodic memory developed to flexibly and creatively combine and rearrange memories of prior events in order to plan for the future, then it is quite a good system. We argue that consciousness originally developed as part of the episodic memory system-quite likely the part needed to accomplish that flexible recombining of information. We posit further that consciousness was subsequently co-opted to produce other functions that are not directly relevant to memory per se, such as problem-solving, abstract thinking, and language. We suggest that this theory is compatible with many phenomena, such as the slow speed and the after-the-fact order of consciousness, that cannot be explained well by other theories. We believe that our theory may have profound implications for understanding intentional action and consciousness in general. Moreover, we suggest that episodic memory and its associated memory systems of sensory, working, and semantic memory as a whole ought to be considered together as the conscious memory system in that they, together, give rise to the phenomenon of consciousness. Lastly, we suggest that the cerebral cortex is the part of the brain that makes consciousness possible, and that every cortical region contributes to this conscious memory system.

Background: Co-occurring somatoform symptoms complicate the diagnosis and treatment of Parkinson disease (PD).

Objective: To learn more about the relationship between somatoform symptoms and PD by comparing demographic and clinical features across PD groups differing in somatoform symptom severity.

Method: Using standardized Brief Symptom Inventory-18 (BSI-18) scores to measure somatoform symptom severity, we assigned 1093 individuals with PD to one of four subgroups using comparisons to normative means: low (M < -½ SD), average (M ± ½ SD), high (M +½ SD to +1 SD), very high (M > +1 SD). We used demographics and disease severity measures to assess each subgroup.

Results: Most of the individuals with PD (56%) had high or very high somatoform symptom levels. Increased somatoform symptom levels were associated with female gender, lower socioeconomic status, greater disease duration, increased PD severity (Total Unified Parkinson's Disease Rating Scale), greater disability (Older Americans Resource and Services Disability subscale), increased BSI-18 Depression and Anxiety subscale scores, lower cognitive function (Mini-Mental State Examination), lower self-efficacy scores (Self-Efficacy to Manage Chronic Disease Scale), lower quality of life scores (SF-12 Health Status Survey), and greater medical comorbidity (Cumulative Illness Rating Scale-Geriatrics) (all comparisons: P < 0.001). We found no significant between-group differences for age, race, or marital status.

Conclusion: Somatoform symptom severity in individuals with PD is associated with greater PD severity and disability and is more common in females and in individuals with low socioeconomic status. Greater awareness of somatoform symptoms should help improve PD treatment.

Background: Whether the effect of switch probability on switch and mixing costs is explained by an activation or preparation account is unclear.

Objective: To investigate the account of the effect of switch probability on switch and mixing costs.

Method: We used a cued task-switching paradigm with three switch probabilities (high, 75%; medium, 50%; and low, 25%) with 19 healthy young adults and recorded the cue- and target-locked event-related potentials (ERPs) and behavioral performance. The task included switch and stay trials under high, medium, and low switch conditions, as well as pure trials.

Results: There was no significant difference in reaction time (RT) in switch and mixing costs between the high and medium switch conditions. The RT in switch and mixing costs in the high and medium switch conditions was significantly less and more than in the low switch condition, respectively. The cue-locked ERPs revealed significant effects on mixing costs (stay - pure) that were cue early frontal positivity (260-300 ms) in the high and medium switch conditions, and on switch costs (switch - stay) that were cue early central positivity (240-260 ms) in the low switch condition. Moreover, the target-locked ERPs of the mixing costs revealed significant effects on mixing costs that were target P3b (440-540 ms) in all three switch conditions, and on switch costs that were target P3b in the medium and low switch conditions.

Conclusion: The effect of switch probability on switch and mixing costs is explained by the activation account.

Background: Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic small-vessel disease that is characterized by a wide range of neurologic and neuropsychological impairments. Constructional impairments have been reported in some cases but have never been assessed systematically.

Objective: To evaluate constructional abilities and their cognitive and neural correlates in nondemented individuals with CADASIL.

Method: Thirty individuals with CADASIL who were not affected by clinically relevant cognitive deterioration and 30 healthy controls (HC) underwent an extensive cognitive assessment and paper-and-pencil visuoconstructional tasks in order to detect constructional impairments. Performance on the visuoconstructional tasks was correlated with the cognitive assessment scores and with quantitative indices of regional gray matter atrophy (obtained via FreeSurfer image analysis) and white matter involvement.

Results: The individuals with CADASIL achieved significantly lower scores on the cognitive assessment compared with the HC. Poor visuoconstructional abilities were observed in seven (23.3%) of the individuals with CADASIL when performing the copy drawing task and in nine (30%) when performing the Rey Complex Figure Test. Logistic regression revealed that visuoconstructional impairments were significantly associated with scores on the Frontal Assessment Battery and the Attentional Matrices Test. Morphometric results revealed that scores on the visuoconstructional tasks were related to gray matter atrophy of the left frontal lobe and right parietal lobe.

Conclusion: Impairments on visuoconstructional tasks are quite common in individuals with CADASIL, even in the lack of clinically relevant cognitive deterioration, and are critically related to frontal and parietal atrophy.