The impact of early-onset cannabis use on functional brain correlates of working memory

ObjectivePrevious studies on the impact of cannabis use disorders (CU) on outcome in psychosis were mostly based on non-representative samples, have often not controlled for confounders and rarely focused on adolescents. Thus, the aims of the present study were to assess;(i) prevalence of CU;(ii) pre-treatment and baseline differences between CU and those without CU (NCU); and(iii) the impact of baseline and course of CU on 18-month outcomes in a representative cohort of adolescents with early onset first episode psychosis (EOP).MethodThe sample comprised 99 adolescents (age 14 to 18) with EOP (onset age 14 to 17), admitted to the Early Psychosis Prevention and Intervention Centre in Australia. Data were collected from medical files using a standardized questionnaire.ResultsPrevalence of lifetime CU was 65.7%, baseline CU 53.5%, and persistent CU 26.3%. Baseline CU compared to NCU was associated with higher illness-severity, lower functioning, less insight, lower premorbid functioning and longer duration of untreated psychosis. Compared to both NCU and those who decreased or stopped CU during treatment, only persistent CU was linked to worse outcomes and more service disengagement. Effect sizes were medium controlling for relevant confounders. Medication non-adherence did not explain the link between persistent CU and worse outcome.ConclusionsThe prevalence of CU in adolescents with EOP is high, while only persistent CU use was associated with worse outcome with medium effect sizes. Specific needs of adolescent patients with respect to cannabis interventions within integrated care settings should be addressed in future studies.

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Striatal iron content is linked to reduced fronto-striatal brain function under working memory load

10.1101/812602 ◽

2019 ◽

Author(s):

Karen M. Rodrigue ◽

Ana M. Daugherty ◽

Chris M. Foster ◽

Kristen M. Kennedy

Keyword(s):

Working Memory ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Iron Content ◽

Brain Function ◽

Memory Load ◽

Dependent Manner ◽

Working Memory Load ◽

Functional Brain ◽

The Impact

AbstractNon-heme iron accumulation contributes to age-related decline in brain structure and cognition via a cascade of oxidative stress and inflammation, although its effect on brain function is largely unexplored. Thus, we examine the impact of striatal iron on dynamic range of BOLD modulation to working memory load. N=166 healthy adults (age 20-94) underwent cognitive testing and an imaging session including n-back (0-, 2-, 3-, and 4-back fMRI), R2*-weighted imaging, and pcASL to measure cerebral blood flow. A statistical model was constructed to predict voxelwise BOLD modulation by age, striatal iron content and an age × iron interaction, controlling for cerebral blood flow, sex, and task response time. A significant interaction between age and striatal iron content on BOLD modulation was found selectively in the putamen, caudate, and inferior frontal gyrus. Greater iron was associated with reduced modulation to difficulty, particularly in middle-aged and younger adults with greater iron content. Further, iron-related decreases in modulation were associated with poorer executive function in an age-dependent manner. These results suggest that iron may contribute to differences in functional brain activation prior to older adulthood, highlighting the potential role of iron as an early factor contributing to trajectories of functional brain aging.

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Testing the association between tobacco and cannabis use and cognitive functioning: Findings from an observational and Mendelian randomization study

10.1101/2020.02.26.20028274 ◽

2020 ◽

Author(s):

Liam Mahedy ◽

Robyn Wootton ◽

Steph Suddell ◽

Caroline Skirrow ◽

Matt Field ◽

...

Keyword(s):

Working Memory ◽

Cognitive Functioning ◽

Early Onset ◽

Latent Class ◽

Mendelian Randomization ◽

Late Onset ◽

Smoking Initiation ◽

Cannabis Use ◽

Additional Support ◽

Study Designs

AbstractBackgroundAlthough studies have examined the association between tobacco and cannabis use in adolescence with subsequent cognitive functioning, study designs are usually not able to distinguish correlation from causation.MethodsFirst, separate patterns of tobacco and cannabis use were derived using longitudinal latent class analysis based on measures assessed on five occasions from ages 13 to 18 years in a large UK based population cohort (ALSPAC). Cognitive functioning measures comprised working memory, response inhibition, and emotion recognition assessed at 24 years of age. One- and two-sample Mendelian randomization, methods for testing causal inference using genetic variants as proxies for an exposure of interest, were used to examine the causal relationship between smoking initiation/lifetime cannabis use, and subsequent cognitive functioning in ALSPAC.ResultsWe found evidence of a relationship between tobacco and cannabis use and diminished cognitive functioning for each of the outcomes in the observational analyses. The clearest evidence demonstrated a dose-response relationship between tobacco use and working memory suggesting late-onset regular tobacco smokers (b=-0.29, 95%CI=-0.45 to - 0.13), early-onset regular smokers (b=-0.45, 95%CI=-0.84 to -0.05), and early-onset regular cannabis users (b=-0.62, 95%CI=-0.93 to -0.31) performed worse on this task compared to individuals with a very low probability of using tobacco/cannabis. Mendelian randomization analyses were imprecise and did not provide additional support for these results.ConclusionsOverall, there was some evidence to suggest that adolescent tobacco and cannabis use were associated with diminished cognitive functioning. Better powered genetic studies are required to determine whether these associations are causal.

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The Impact of Cannabis Abuse on Psychotic Symptoms and Their Severity among Cannabis Associated Psychosis Subjects: An Indian Experience

Psychocentrum Review ◽

10.26539/pcr.31577 ◽

2021 ◽

Vol 3 (1) ◽

pp. 31-38

Author(s):

Ramchandra Lamba ◽

Sona Budaniya ◽

Rajendera Kumar Acharya ◽

Ram Kumar Solanki ◽

Ashok Kumar

Keyword(s):

Early Onset ◽

Pearson Correlation ◽

Tertiary Care ◽

Cross Sectional Study ◽

Severe Form ◽

Cannabis Use ◽

Psychotic Symptoms ◽

Cross Sectional ◽

Cannabis Abuse ◽

The Impact

Use of cannabis for recreational, religious and cultures has been prevalent since ancient times. It is one of the commonest used illicit substance. While not all cannabis users develop psychiatric problems, heavy cannabis use may increase the risk of cognitive abnormalities, psychotic illness and mood disorders. This research aimed to evaluate severity of various psychotic symptoms in relation to variables of cannabis abuse. A cross sectional study of 30 male patients admitted at tertiary care psychiatric center with diagnosis of cannabis-associated psychosis was carried out. Cannabis abuse variables along with psychotic symptoms severity on BPRS scale were obtained. Correlation between variables of cannabis abuse and psychotic symptoms and total BPRS score were derived using Pearson correlation 2- tailed test. Hostility (83%) and excitement (77%) were most prevalent symptoms with increased severity followed by elevated mood, grandiosity, suspiciousness and motor hyperactivity. Patients with long duration and early onset of cannabis abuse presented with more severe form of psychosis. Frequency of cannabis use was not significantly correlated with total BPRS score, although amount spent over cannabis was significantly associated with total BPRS score. Family history of cannabis abuse predicted early onset of cannabis abuse.

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Spatial patterns in functional brain connectomes reflect acute and chronic cannabis use

10.1101/2021.03.08.434333 ◽

2021 ◽

Author(s):

JG Ramaekers ◽

NL Mason ◽

SW Toennes ◽

EL Theunissen ◽

E Amico

Keyword(s):

Spatial Patterns ◽

Resting State ◽

A Priori ◽

Brain Regions ◽

Brain Network ◽

Cannabis Use ◽

Connectivity Pattern ◽

Functional Brain ◽

Acute And Chronic Exposure ◽

The Impact

AbstractResting state fMRI has been employed to identify alterations in functional connectivity within or between brain regions following acute and chronic exposure to Δ9-tetrahydrocannabinol (THC), the psychoactive component in cannabis. Most studies focused a priori on a limited number of local brain areas or circuits, without considering the impact of cannabis on wholebrain network organization. The present study attempted to identify changes in the wholebrain human functional connectome as assessed with ultra-high field (7T) resting state scans of occasional (N=12) and chronic cannabis users (N=14) during placebo and following vaporization of cannabis. Two distinct data-driven methodologies, i.e. network-based statistics (NBS) and connICA, were used to identify changes in functional connectomes associated with acute cannabis intoxication and chronic cannabis use. Both methodologies revealed a broad state of hyperconnectivity within the entire range of major brain networks in chronic cannabis users compared to occasional cannabis users, which might be reflective of an adaptive network reorganization following prolonged cannabis exposure. The connICA methodology also extracted a distinct spatial connectivity pattern of hypoconnectivity involving the dorsal attention, limbic, subcortical and cerebellum networks and of hyperconnectivity between the default mode and ventral attention network, that was associated with the feeling of subjective high during THC intoxication across both user groups. Whole-brain network approaches identified spatial patterns in functional brain connectomes that distinguished acute from chronic cannabis use, and offer an important utility for probing the interplay between short and long-term alterations in functional brain dynamics when progressing from occasional to chronic use of cannabis.

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Early onset of cannabis use and violent behavior in psychosis

European Psychiatry ◽

10.1192/j.eurpsy.2020.71 ◽

2020 ◽

Vol 63 (1) ◽

Author(s):

Valerie Moulin ◽

Luis Alameda ◽

David Framorando ◽

Philipp-S Baumann ◽

Mehdi Gholam ◽

...

Keyword(s):

Risk Factors ◽

Substance Use ◽

Early Onset ◽

Psychotic Disorders ◽

Age Of Onset ◽

Violent Behavior ◽

Age At Onset ◽

Cannabis Use ◽

Early Psychosis ◽

The Impact

Abstract Background: Although evidence from psychosis patients demonstrates the adverse effects of cannabis use (CU) at a young age and that the rate of CU is high in subgroups of young violent patients with psychotic disorders, little is known about the possible effect of the age of onset of CU on later violent behaviors (VB). So, we aimed to explore the impact of age at onset of CU on the risk of displaying VB in a cohort of early psychosis patients. Method: Data were collected prospectively over a 36-month period in the context of an early psychosis cohort study. A total of 265 patients, aged 18–35 years, were included in the study. Logistic regression was performed to assess the link between age of onset of substance use and VB. Results: Among the 265 patients, 72 had displayed VB and 193 had not. While violent patients began using cannabis on average at age 15.29 (0.45), nonviolent patients had started on average at age 16.97 (0.35) (p = 0.004). Early-onset CU (up to age 15) was a risk factor for VB (odds ratio = 4.47, confidence interval [CI]: 1.13–20.06) when the model was adjusted for age group, other types of substance use, being a user or a nonuser and various violence risk factors and covariates. History of violence and early CU (until 15) were the two main risk factors for VB. Conclusions: Our results suggest that early-onset CU may play a role in the emergence of VB in early psychosis.

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What Is Personality?

The Fragmented Personality ◽

10.1093/med/9780190884574.003.0002 ◽

2018 ◽

pp. 7-82

Author(s):

Dragan M. Svrakic ◽

Mirjana Divac-Jovanovic

Keyword(s):

Working Memory ◽

Mental Life ◽

Functional Brain ◽

Self Reflection ◽

Liquid Modernity ◽

Mental Experience ◽

Functional Brain Networks ◽

The Mind ◽

Memory Support ◽

The Impact

This chapter reviews the neuroscience of brain and mind development. Recent advances in cognitive neuroscience, such as the concept of nonconscious working memory, support the psychanalytic concept of early object relations, which are believed to be the “elementary particles of the mind”: each contains a percept, a self-reflection, and the related affect and thus is not divisible to lower order units of mental experience. The functional brain networks giving rise to mental faculties (cognition, motivation, and emotions) are informed by these highly personal units of experience. Such “personalized” mental faculties self-organize into semistable subsystems within the mind, each providing a specific adaptive advantage to the mind as a whole. The impact of sociocultural transitions on human mental life, as well as the concepts of normal, postmodern, and fluid self in the context of conservativism, postmodernism, and liquid modernity, are discussed in detail.

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Do Children With Developmental Language Disorder (DLD) Have Difficulties With Interference Control, Visuospatial Working Memory, and Selective Attention? Developmental Patterns and the Role of Severity and Persistence of DLD

Journal of Speech Language and Hearing Research ◽

10.1044/2020_jslhr-20-00012 ◽

2020 ◽

Vol 63 (9) ◽

pp. 3036-3050

Author(s):

Elma Blom ◽

Tessel Boerma

Keyword(s):

Working Memory ◽

Selective Attention ◽

Language Disorder ◽

Typically Developing ◽

Developmental Language Disorder ◽

Visuospatial Working Memory ◽

Interference Control ◽

Developmental Patterns ◽

Search Tasks ◽

The Impact

Purpose Many children with developmental language disorder (DLD) have weaknesses in executive functioning (EF), specifically in tasks testing interference control and working memory. It is unknown how EF develops in children with DLD, if EF abilities are related to DLD severity and persistence, and if EF weaknesses expand to selective attention. This study aimed to address these gaps. Method Data from 78 children with DLD and 39 typically developing (TD) children were collected at three times with 1-year intervals. At Time 1, the children were 5 or 6 years old. Flanker, Dot Matrix, and Sky Search tasks tested interference control, visuospatial working memory, and selective attention, respectively. DLD severity was based on children's language ability. DLD persistence was based on stability of the DLD diagnosis. Results Performance on all tasks improved in both groups. TD children outperformed children with DLD on interference control. No differences were found for visuospatial working memory and selective attention. An interference control gap between the DLD and TD groups emerged between Time 1 and Time 2. Severity and persistence of DLD were related to interference control and working memory; the impact on working memory was stronger. Selective attention was unrelated to DLD severity and persistence. Conclusions Age and DLD severity and persistence determine whether or not children with DLD show EF weaknesses. Interference control is most clearly impaired in children with DLD who are 6 years and older. Visuospatial working memory is impaired in children with severe and persistent DLD. Selective attention is spared.

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Development of Reading Remediation for Dyslexic Individuals

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000259 ◽

2016 ◽

Vol 224 (4) ◽

pp. 240-246 ◽

Cited By ~ 4

Author(s):

Mélanie Bédard ◽

Line Laplante ◽

Julien Mercier

Keyword(s):

20Th Century ◽

Scientific Literature ◽

Behavioral Data ◽

Educational Neuroscience ◽

Reading Remediation ◽

Functional Brain ◽

Neurophysiological Data ◽

Brain Correlates ◽

Research Questions ◽

The Brain

Abstract. Dyslexia is a phenomenon for which the brain correlates have been studied since the beginning of the 20th century. Simultaneously, the field of education has also been studying dyslexia and its remediation, mainly through behavioral data. The last two decades have seen a growing interest in integrating neuroscience and education. This article provides a quick overview of pertinent scientific literature involving neurophysiological data on functional brain differences in dyslexia and discusses their very limited influence on the development of reading remediation for dyslexic individuals. Nevertheless, it appears that if certain conditions are met – related to the key elements of educational neuroscience and to the nature of the research questions – conceivable benefits can be expected from the integration of neurophysiological data with educational research. When neurophysiological data can be employed to overcome the limits of using behavioral data alone, researchers can both unravel phenomenon otherwise impossible to document and raise new questions.

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