Making memories: the development of long-term visual knowledge in children with visual agnosia

There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2 years and 3.7 years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment

Developmental delay in early childhood is associated with visual-constructive skills at school age in a Brazilian cohort

Abstract We investigated differences in IQ and visual-constructive skills in school-age children evaluated as developmentally delayed or typically developed in early childhood. Sixty-four participants from a Brazilian cohort were evaluated in IQ (Wechsler Abbreviated Scale of Intelligence) and tasks of visual-spatial memory and visual-constructive skills through the Benton Visual Retention Test (BVRT) at school age. Neuropsychomotor development at 4 years of age was measured by Denver II. Developmentally delayed children showed lower IQs, lower scores, and more errors in copy and memory BVRT tasks when compared to typically developed children. Delay in neuropsychomotor development in early childhood may affect the subsequent cognitive development of children

Blindsight following visual cortex deafferentation disappears with purple and red stimuli: A case study.

We employed a redundant signal effect (RSE) paradigm to ascertain the role of the superior colliculus (SC) in blindsight. The RSE consists of the speeding of reaction time (RT) to double versus single stimuli. One patient with a unilateral lesion of the optic radiation and consequent hemianopia showed a RSE with pairs of visual stimuli presented across the vertical meridian despite seeing only stimuli in the intact hemifield. However, when, instead of achromatic stimuli we used short or long wavelength stimuli the implicit RSE disappeared. This result raises the possibility that implicit chromatic processing in the affected hemifield might have a different neural substrate following deafferentation with respect to lesion of the primary visual cortex

Retinal eccentricity effects on reaction time to imagined stimuli

To cast light on the possible neural substrate of visual imagery we tested normal participants and one hemianopic patient on simple reaction time (RT) to real and imagined visual stimuli. In one experiment participants were to detect as quickly as possible a luminous square presented at one out of two different retinal eccentricities. A well known effect with visual stimuli is that RT is slower for peripheral versus central stimuli. We found that imagined stimuli showed an eccentricity effect similar to that obtained with real stimuli. However, this was not the case in a patient with a hemianopic visual field loss (quadrantanopia) as a result of damage to the optic radiation. Even though the patient showed no difficulty in imaging stimuli in the affected hemifield she did not show an eccentricity effect as was the case in her intact side. In a second experiment, normal participants showed faster RT to stimuli of larger size with either real or imagined stimuli. Overall, these results show that visual perception and imagination share a similar visuotopic organisation that is disrupted following deafferentation of the visual cortex

Pop Music & Frontotemporal Dementia

Dementia is generally regarded as a condition marked by losses: loss of memory, reasoning abilities, and language, for example. However, this is not always the case. In frontotemporal dementia (FTD), behaviors deviating from the patients prior set of norms and standards frequently occur. The authors report the cases of 2 individuals (aged 68 and 73 yrs) with FTD who experienced a change in musical taste that might represent a singular gain. A possible hypothesis to explain this behavior is that it could be the consequence of an unspecific change in attitude to novelty. It has been suggested that novelty is managed by the right frontal lobe, and a disproportionate functional prevalence of the right over the left frontal lobe might lead to novelty seeking. However, this does not seem to be the case in these patients, who showed basically symmetric involvement of the frontal lobes. (PsycINFO Database Record (c) 2016 APA, all rights reserved

Clinical and genetic study of a family with a paternally inherited 15q11-q13 duplication.

Interstitial chromosome 15q11-q13 duplications are associated with developmental delay, behavioral problems and additional manifestations, including epilepsy. In most affected individuals the duplicated chromosome is maternally derived, whereas paternal inheritance is more often associated with a normal phenotype. Seizures have not been described in patients with paternal dup 15q11-q13. We describe a family with five individuals in three generations with a paternally-inherited 15q11-q13 duplication, four of whom exhibited abnormal phenotypic characteristics, including seizures. The 18-year-old female proband presented with moderate intellectual disability, obesity, and epilepsy. Her brother manifested learning disability and behavioral problems. They both inherited the 15q11-q13 dup from their father who had a normal phenotype. Their paternal uncle and grandfather also had the duplication and were reported to have had seizures. Array-CGH and MLPA analyses showed that the duplication included the TUBGCP5, CYFIP1, MKRN3, MAGEL2, NDN, SNRPN, UBE3A, ATP10A, GABRB3, GABRA5, GABRG3, and OCA2 genes. This report provides evidence for intrafamilial phenotypic variability of paternal dup 15q11-q13, ranging from normal to intellectual disability and seizures, and potentially expanding the phenotype of paternal 15q11-q13 interstitial duplications

Maintenance Cognitive Stimulation Therapy (CST) for dementia: a single-blind, multi-centre, randomized controlled trial of Maintenance CST vs. CST for dementia

Background: Psychological treatments for dementia are widely used in the UK and internationally, but only rarely have they been standardised, adequately evaluated or systematically implemented. There is increasing recognition that psychosocial interventions may have similar levels of effectiveness to medication, and both can be used in combination. Cognitive Stimulation Therapy (CST) is a 7-week cognitive-based approach for dementia that has been shown to be beneficial for cognition and quality of life and is cost-effective, but there is less conclusive evidence for the effects of CST over an extended period. Methods/Design: This multi-centre, pragmatic randomised controlled trial (RCT) to assess the effectiveness and costeffectiveness of Maintenance CST groups for dementia compares a intervention group who receive CST for 7 weeks followed by the Maintenance CST programme once a week for 24 weeks with the control group who receive CST for 7 weeks, followed by treatment as usual for 24 weeks. The primary outcome measures are quality of life of people with dementia assessed by the QoL-AD and cognition assessed by the ADAS-Cog. Secondary outcomes include the person with dementia's mood, behaviour, activities of daily living, ability to communicate and costs; as well as caregiver health-related quality of life. Using a 5% significance level, comparison of 230 participants will yield 80% power to detect a standardised difference of 0.39 on the ADAS-Cog between the groups. The trial includes a cost-effectiveness analysis from a public sector perspective. Discussion: A pilot study of longer-term Maintenance CST, offering 16 weekly sessions of maintenance following the initial CST programme, previously found a significant improvement in cognitive function (MMSE) for those on the intervention group. The study identified the need for a large-scale, multi-centre RCT to define the potential longerterm benefits of continuing the therapy. This study aims to provide definitive evidence of the potential efficacy of maintenance CST and establish how far the long-term benefits can be compared with antidementia drugs such as cholinesterase inhibitors. Trial Registration: ISRCTN2628606

The effect of stimulation therapy and donepezil on cognitive function in Alzheimer's disease. A community based RCT with a two-by-two factorial design

This article is part of Fred Andersen's doctoral thesis. Available in Munin at http://hdl.handle.net/10037/3669Progressive neurodegeneration in Alzheimer’s disease (AD) induces cognitive deterioration, and there is controversy regarding the optimal treatment strategy in early AD. Stimulation therapy, including physical exercise and cholinesterase inhibitors are both reported to postpone cognitive deterioration in separate studies. We aimed to study the effect of stimulation therapy and the additional effect of donepezil on cognitive function in early AD. Design: A two-by-two factorial trial comprising stimulation therapy for one year compared to standard care to which a randomized double-blinded placebo controlled trial with donepezil was added. Setting: Nine rural municipalities in Northern Norway. Participants: 187 participants 65 years and older with a recent diagnosis of mild or moderate AD were included in the study of which 146 completed a one-year follow-up. INTERVENTIONS: In five municipalities the participants received stimulation therapy whereas participants in four received standard care. All participants were randomised double-blindly to donepezil or placebo and tested with three different cognitive tests four times during the one-year study period. Main outcome: Changes in MMSE sum score. Secondary outcome: Changes in ADAS-Cog and Clock Drawing Test. MMSE scores remained unchanged amongst AD participants receiving stimulation therapy and those receiving standard care. The results were consistent for ADAS-Cog and Clock Drawing Test. No time trend differences were found during one-year follow-up between groups receiving stimulation therapy versus standard care or between donepezil versus placebo. In rural AD patients non-pharmacological and pharmacological therapy did not improve outcome compared with standard care but all groups retained cognitive function during one year follow-up. Other studies are needed to confirm these results