Abstract Personality dimensions such as novelty seeking (NS), harm avoidance (HA), reward dependence (RD) and persistence (PER) are said to be heritable, stable across time and dependent on genetic ...and neurobiological factors. Recently a better understanding of the relationship between personality traits and brain structures/systems has become possible due to advances in neuroimaging techniques. This Magnetic Resonance Imaging (MRI) study investigated if individual differences in these personality traits reflected structural variance in specific brain regions. A large sample of eighty five young adult participants completed the Three-dimensional Personality Questionnaire (TPQ) and had their brain imaged with MRI. A voxel-based correlation analysis was carried out between individuals’ personality trait scores and grey matter volume values extracted from 3D brain scans. NS correlated positively with grey matter volume in frontal and posterior cingulate regions. HA showed a negative correlation with grey matter volume in orbito-frontal, occipital and parietal structures. RD was negatively correlated with grey matter volume in the caudate nucleus and in the rectal frontal gyrus. PER showed a positive correlation with grey matter volume in the precuneus, paracentral lobule and parahippocampal gyrus. These results indicate that individual differences in the main personality dimensions of NS, HA, RD and PER, may reflect structural variance in specific brain areas.
The rate of cognitive and functional decline in Alzheimer's disease (AD) changes across individuals.
Our purpose was to assess whether the concept of "fast decline" really fits its definition and ...whether cognitive and functional variables at onset can predict the progression of AD.
324 AD patients were included. We retrospectively examined their Mini-Mental State Examination (MMSE) total score and sub-items, Activities of Daily Living (ADL), and Instrumental Activities of Daily Living (IADL) at baseline and every six months for a 4-year follow-up. Patients were divided into "fast decliners" (n = 62), defined by a loss ≥5 points on the MMSE score within the first year from the baseline; "intermediate decliners" (n = 37), by a loss ≥5 points after the first year and before the 18th month; or "slow decliners" (n = 225), composed of the remaining patients.
At baseline, the groups did not differ on demographic, clinical, and cognitive variables. The decline at the end of the 4-year follow-up period seems to be similar among the different decline clusters. Predictors of disease progression have not been identified; only the MMSE total score at 12 months <14/30 was indicative of a poor prognosis.
Even with the limitation due to the small sample size, the lack of differences in the disease progression in time in the different clusters suggest the inconsistency of the so-called "fast decliners". This study was unable to show any significant difference among clusters of AD progression within a 4-year time interval. Further studies should better clarify whether a more consistent distinction exists between slow and fast decliners.
Cognitive stimulation therapy (CST) is an evidence-based psychosocial intervention for people with mild-to-moderate dementia due to various etiological factors.
The aim of the present study was to ...assess the efficacy of the CST program, Italian adaptation -CST-IT-, in individuals who have vascular dementia (VaD).
Older adults with mild-to-moderate VaD (N = 35) were assigned to one of two programs: one group (N = 21) attended the 14 sessions of the CST-IT program, while the other, active control group (N = 14) took part in alternative activities. The following domains were examined: cognitive functioning, quality of life, mood, behavior, functional activities of daily living.
Compared with the active controls, the CST-IT group showed a greater improvement in general cognitive functioning after the intervention (i.e. score increase on the Mini-Mental State Examination and decrease on the Alzheimer's Disease Assessment Scale - Cognitive subscale). A trend towards improvement was also identified in short-term/working memory - the backward digit span task- and perceived quality of life (Quality of Life - Alzheimer's Disease scale). No significant differences emerged between the two groups for the other domains considered.
The present results support the efficacy of CST in people with vascular dementia.
Recently, efforts have been made to combine complementary perspectives in the assessment of Alzheimer type dementia. Of particular interest is the definition of the fingerprints of an early stage of ...the disease known as Mild Cognitive Impairment or prodromal Alzheimer's Disease. Machine learning approaches have been shown to be extremely suitable for the implementation of such a combination.
In the present pilot study we combined the machine learning approach with structural magnetic resonance imaging and cognitive test assessments to classify a small cohort of 11 healthy participants and 11 patients experiencing Mild Cognitive Impairment. Cognitive assessment included a battery of standardised tests and a battery of experimental visuospatial memory tests. Correct classification was achieved in 100% of the participants, suggesting that the combination of neuroimaging with more complex cognitive tests is suitable for early detection of Alzheimer Disease.
In particular, the results highlighted the importance of the experimental visuospatial memory test battery in the efficiency of classification, suggesting that the high-level brain computational framework underpinning the participant's performance in these ecological tests may represent a "natural filter" in the exploration of cognitive patterns of information able to identify early signs of the disease.
Fronto-temporal dementia (FTD) is the clinical-diagnostic term that is now preferred to describe patients with a range of progressive dementia syndromes associated with focal atrophy of the frontal ...and anterior temporal cerebral regions. Currently available FTD medications have been used to control behavioral symptoms, even though they are ineffective in some patients, expensive and may induce adverse effects. Alternative therapeutic approaches are worth pursuing, such as non-invasive brain stimulation with transcranial direct current (tDCS). tDCS has been demonstrated to influence neuronal excitability and reported to enhance cognitive performance in dementia. The aim of this study was to investigate whether applying Anodal tDCS (2 mA intensity, 20 min) over the fronto-temporal cortex bilaterally in five consecutive daily sessions would improve cognitive performance and behavior symptoms in FTD patients, also considering the neuromodulatory effect of stimulation on cortical electrical activity measured through EEG. We recruited 13 patients with FTD and we tested the effect of Anodal and Sham (i.e., placebo) tDCS in two separate experimental sessions. In each session, at baseline (T0), after 5 consecutive days (T1), after 1 week (T2), and after 4 weeks (T3) from the end of the treatment, cognitive and behavioral functions were tested. EEG (21 electrodes, 10-20 international system) was recorded for 5 min with eyes closed at the same time points in nine patients. The present findings showed that Anodal tDCS applied bilaterally over the fronto-temporal cortex significantly improves (1) neuropsychiatric symptoms (as measured by the neuropsychiatric inventory, NPI) in FTD patients immediately after tDCS treatment, and (2) simple visual reaction times (sVRTs) up to 1 month after tDCS treatment. These cognitive improvements significantly correlate with the time course of the slow EEG oscillations (delta and theta bands) measured at the same time points. Even though further studies on larger samples are needed, these findings support the effectiveness of Anodal tDCS over the fronto-temporal regions in FTD on attentional processes that might be correlated to a normalized EEG low-frequency pattern.
Semantic memory decline has been found in mild cognitive impairment (MCI). In this study performance on a range of semantic tasks and structural brain patterns were examined in a group of MCI ...patients. Fourteen MCI and sixteen healthy elderly controls underwent semantic memory assessment and MRI brain scanning. The cognitive battery included visual naming and naming from definition tasks for objects, actions and famous people, semantic fluency for animals, fruits, tools, furniture, singers, politicians, actions, word-association task for early and late acquired words and a reading task. MCI patients performed worse on semantic fluency in all categories except for tools, produced a smaller number of words associated with early acquired nouns and a smaller total number of word-associations. Patients scored more poorly in all tasks of naming, naming of famous people, overall reading and reading of famous people's names. MCIs had fewer correct immediate recalls and more correct responses with cue in famous people naming, made more errors in naming and in the naming from definition task for famous people. Grey matter reduction in parahippocampus, frontal and cingulate cortices and amygdala was found in the MCI sample when compared with controls. Patients presented a different pattern of brain areas correlated with semantic tasks from that seen in controls, with more extensive involvement of subcortical regions in semantic fluency and word-association and more contribution of frontal than temporo-parietal areas in visual naming. This evidence suggests a reorganization of cortical associations of semantic processes in MCI that, following damage in the semantic circuit, explains its progressive breakdown.
Objective: The aim of this study was to determine which characteristics could better distinguish dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) at the mild cognitive impairment (MCI) ...stage, with particular emphasis on visual space and object perception abilities. Methods: Fifty-three patients with mild cognitive deficits that were eventually diagnosed with probable DLB (MCI-DLB: n = 25) and AD (MCI-AD: n = 28) at a 3-year follow-up were retrospectively studied. At the first visit, the patients underwent cognitive assessment including the Qualitative Scoring Mini Mental State Examination Pentagon Test and the Visual Object and Space Perception Battery. The Neuropsychiatric Inventory Questionnaire, Unified Parkinson's Disease Rating Scale (UPDRS) and questionnaires for cognitive fluctuations and sleep disorders were also administered. Results: The best clinical predictor of DLB was the presence of soft extrapyramidal signs (mean UPDRS score: 4.04 ± 5.9) detected in 72% of patients, followed by REM sleep behavior disorder (60%) and fluctuations (60%). Wrong performances in the pentagon's number of angles were obtained in 44% of DLB and 3.7% of AD patients and correlated with speed of visual attention. Executive functions, visual attention and visuospatial abilities were worse in DLB, while verbal episodic memory impairment was greater in AD. Deficits in the visual-perceptual domain were present in both MCI-DLB and AD. Conclusions: Poor performance in the pentagon's number of angles is specific of DLB and correlates with speed of visual attention. The dorsal visual stream seems specifically more impaired in MCI-DLB with respect to the ventral visual stream, the latter being involved in both DLB and AD. These cognitive features, associated with subtle extrapyramidal signs, should alert clinicians to a diagnostic hypothesis of DLB.
Highlights ► Cocaine abusers had less grey matter in occipital and insular regions than controls. ► Heroin abusers had lower grey matter values in the insula than controls. ► Cocaine abusers had less ...grey matter in limbic regions than heroin abusers. ► Heroin abusers showed less grey matter in parietal regions, than cocaine abusers. ► Insular deficits might constitute a vulnerability trait to addiction.
Imagery is a multi-componential process involving different mental operations. This paper addresses whether separate processes underlie the generation, maintenance and transformation of mental images ...or whether these cognitive processes rely on the same mental functions. We also examine the influence of age on these mental operations for independence of components. In Experiment 1, younger (22 years) and older (69 years) adults generated and maintained general, specific, contextual and autobiographical visual mental images evoked in response to concrete nouns. The older adults had longer generation times, but there was no difference between the two groups on maintenance. Both groups had shortest generation and maintenance times for general images, whereas only the older adults took longest in generating autobiographical images. In Experiment 2, the total maintenance time and number of transformations for each type of image were compared in another group of younger and older adults. General images were less transformed and more subject to decay for both groups. The older people maintained the autobiographical mental images for longest compared to other image types. In conclusion, image generation, maintenance and transformation seem to be differently affected by type of image and aging, supporting a model of their cognitive segregation.
This study investigated the cognitive profile and the cerebral perfusion pattern in a highly educated 70 year old gentleman with posterior cortical atrophy (PCA). Visuo-perceptual abilities, spatial ...memory, spatial representation and navigation, visuo-spatial mental imagery, semantic and episodic-autobiographical memory were assessed. Regional cerebral blood flow (rCBF) was imaged with SPECT. Cognitive testing showed visual-perceptual impairment, apperceptive visual and landmark agnosia, topographical disorientation with way-finding deficits, impaired map learning and poor mental image generation. Semantic memory was normal, while episodic-autobiographical memory was impaired. Reduced rCBF was found mainly in the right hemisphere, in the precentral gyrus, posterior cingulate and middle temporal gyri, cuneus and precuneus, in the left superior temporal and lingual gyri and in the parahippocampus bilaterally. Hypoperfusion in occipito-parietal regions was associated with visuo-spatial deficits, whereas deficits in visuo-spatial mental imagery might reflect dysfunction related to hypoperfusion in the parahippocampus and precuneus, structures which are responsible for spatial and imagery processing. Dissociating performance between preserved semantic memory and poor episodic-autobiographical recall is consistent with a pattern of normal perfusion in frontal and anterior temporal regions but abnormal rCBF in the parahippocampi. The present findings indicate that PCA involves visuo-spatial imagery deficits and provide further validation to current neuro-cognitive models of spatial representation and topographical disorientation.
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