performance

The potential risk of toxoplasmosis for traffic accidents: A systematic review and meta-analysis

February 12, 2018
Gohardehi, S. , Sharif, M. , Sarvi, S., Moosazadeh, M., Alizadeh-Navaei,R., Hosseini,S. A., Amouei,A. , Pagheh, A. , Sadeghi , M., Daryani, A.
Experimental Parasitology 2018; 191: 19-24

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Toxoplasmosis is a prevalent infectious disease. Although most people infected by Toxoplasma gondii are asymptomatic, evidence has suggested that this disease might affect some aspects of a hoses behavior and associate with schizophrenia, suicide attempt, changes in various aspects of personality, and poor neurocognitive performance. These associations may play roles in increasing the risk of a number of incidents, such as traffic accidents, among infected people. In this regard, this study aimed to provide summary estimates for the available data on the potential risk of toxoplasmosis for traffic accidents. To this end, using a number of search terms, i.e. toxoplasmosis, Toxoplasma gondii, traffic accident, road accident car accident, crash, and prevalence, literature searches (up to October 1, 2017) were carried out via 6 databases. The meta-analysis was conducted using the StatsDirect statistical software and a P-value less than 0.05 was regarded as significant in all statistical analyses. Out of 1841 identified studies, 9 studies were finally considered eligible for carrying out this systematic review. Reviewing results of these studies indicated that 5 out of 9 studies reported a significant relationship between Toxoplasma gondii and traffic accidents. Additionally, data related to gender showed significant differences between infected and control men and women. Considering age, reviewing the results of these studies revealed a significant difference between the infected people and the Toxoplasma-negative subjects under 45 years of age. However, no significant difference was found between the two groups aged 45 or older. Given these results, it can be concluded that Toxoplasma gondii significantly increases the risk of having traffic accidents.

Tagged: behavior, gondii infection, latent asymptomatic toxoplasmosis, meta-analysis, performance, systematic review, Toxoplasma gondii, toxoplasmosis, traffic accidents, women

Behavior Reviews

Reduced ERPs and theta oscillations underlie working memory deficits in Toxoplasma gondii infected seniors

October 6, 2016
Gajewski, P. D., Falkenstein, M., Hengstler, J. G., Golka, K.
Psychology 2016; 120: 35-45.

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Toxoplasma gondii is one of the most widespread infections in humans. Recent studies give evidence for memory deficits in infected older adults. To investigate working memory dysfunction in infected elderly, a double-blinded electrophysiological study was conducted. 84 persons derived from a sample of 131 healthy participants with the mean age of 70 years were assigned to two groups of 42 non-infected and 42 infected individuals. The outcome measures were behavioral performance, target and response-related ERPs, and time-frequency wavelets during performance in a n-back working-memory task. The infected individuals showed a reduced rate of detected targets and diminished P3b amplitude both in target-locked as well as response-locked data compared to the non-infected group. Time-frequency decomposition of the EEG-signals revealed lower evoked power in the theta frequency range in the target-locked as well as in the response-locked data in infected individuals. The reported effects were comparable with differences between healthy young and old adults described previously. Taking together, the reduced working-memory performance accompanied by an attenuated P3b and frontal theta activity may suggest neurotransmitter imbalance like dopamine and norepinephrine in T. gondii infected individuals. In face of a high prevalence of T. gondii infection and the increasing ratio of older population their accelerated memory decline may have substantial socioeconomic consequences.

Tagged: (erps) aging, behavior, brain, Dopamine, eeg-dynamics, event-related potentials, latent toxoplasmosis, norepinephrine, p300, performance, response-locked erps, Schizophrenia, stimulus-locked erps, task, theta, time-window, Toxoplasma gondii, working memory

Cognitive functions

Association between latent toxoplasmosis and cognition in adults: a cross-sectional study

October 9, 2015
Gale, S. D., Brown, B. L., Erickson, L. D., Berrett, A., Hedges, D. W.
Parasitology 2015; 142: 557-565

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Latent infection from Toxoplasma gondii (T. gondii) is widespread worldwide and has been associated with cognitive deficits in some but not all animal models and in humans. We tested the hypothesis that latent toxoplasmosis is associated with decreased cognitive function in a large cross-sectional dataset, the National Health and Nutrition Examination Survey (NHANES). There were 4178 participants aged 20-59 years, of whom 191% had IgG antibodies against T. gondii. Two ordinary least squares (OLS) regression models adjusted for the NHANES complex sampling design and weighted to represent the US population were estimated for simple reaction time, processing speed and short-term memory or attention. The first model included only main effects of latent toxoplasmosis and demographic control variables, and the second added interaction terms between latent toxoplasmosis and the poverty-to-income ratio (PIR), educational attainment and race-ethnicity. We also used multivariate models to assess all three cognitive outcomes in the same model. Although the models evaluating main effects only demonstrated no association between latent toxoplasmosis and the cognitive outcomes, significant interactions between latent toxoplasmosis and the PIR, between latent toxoplasmosis and educational attainment, and between latent toxoplasmosis and race-ethnicity indicated that latent toxoplasmosis may adversely affect cognitive function in certain groups.

Tagged: attention, behavior, brain, cognition, deficits, disease, gondii infection, memory, Mexico, performance, processing speed, Schizophrenia, seroprevalence, socioeconomic position, Toxoplasma gondii, toxoplasmosis

Cognitive functions

Toxoplasma gondii seropositivity and cognitive functions in school-aged children

October 6, 2015
Mendy, A., Vieira, E. R., Albatineh, A. N., Gasana, J.
Parasitology 2015; 142: 1221-1227

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Toxoplasma gondii (T. gondii) infects one-third of the world population, but its association with cognitive functions in school-aged children is unclear. We examined the relationship between Toxoplasma seropositivity and neuropsychological tests scores (including math, reading, visuospatial reasoning and verbal memory) in 1755 school-aged children 12-16 years old who participated to the Third National Health and Nutrition Examination Survey, using multiple linear regressions adjusted for covariates. Toxoplasma seroprevalence was 7.7% and seropositivity to the parasite was associated with lower reading skills (regression coefficient [beta] = -5.86, 95% confidence interval [CI]: -11.11, -0.61, P = 0.029) and memory capacities (beta = -0.86, 95% CI: -1.58, -0.15, P = 0.017). The interaction between T. gondii seropositivity and vitamin E significantly correlated with memory scores. In subgroup analysis, Toxoplasma-associated memory impairment was worse in children with lower serum vitamin E concentrations (beta = -1.61, 95% CI: -2.44, -0.77, P < 0.001) than in those with higher values (beta = -0.12, 95% CI: -1.23, 0.99, P = 0.83). In conclusion, Toxoplasma seropositivity may be associated with reading and memory impairments in school-aged children. Serum vitamin E seems to modify the relationship between the parasitic infection and memory deficiency.

Tagged: adults, association, behavior, cognition, cognitive function, disease, Dopamine, gene-expression, infection, intelligence, math, memory, mice, parasites, performance, reading, school-aged children, Toxoplasma gondii, vitamin e, vitamins

Cognitive functions

Interaction between Helicobacter pylori and latent toxoplasmosis and demographic variables on cognitive function in young to middle-aged adults

January 9, 2015
Gale, S. D., Erickson, L. D., Brown, B. L., Hedges, D. W.
Plos One 2015; 10: UNSP e0116874 10.1371/journal.pone.0116874

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Helicobacter pylori and latent toxoplasmosis are widespread diseases that have been associated with cognitive deficits and Alzheimer's disease. We sought to determine whether interactions between Helicobacter pylori and latent toxoplasmosis, age, race-ethnicity, educational attainment, economic status, and general health predict cognitive function in young and middle-aged adults. To do so, we used multivariable regression and multivariate models to analyze data obtained from the United States' National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention, which can be weighted to represent the US population. In this sample, we found that 31.6 percent of women and 36.2 percent of men of the overall sample had IgG Antibodies against Helicobacter pylori, although the seroprevalence of Helicobacter pylori varied with sociodemographic variables. There were no main effects for Helicobacter pylori or latent toxoplasmosis for any of the cognitive measures in models adjusting for age, sex, race-ethnicity, educational attainment, economic standing, and self-rated health predicting cognitive function. However, interactions between Helicobacter pylori and race-ethnicity, educational attainment, latent toxoplasmosis in the fully adjusted models predicted cognitive function. People seropositive for both Helicobacter pylori and latent toxoplasmosis - both of which appear to be common in the general population - appear to be more susceptible to cognitive deficits than are people seropositive for either Helicobacter pylori and or latent toxoplasmosis alone, suggesting a synergistic effect between these two infectious diseases on cognition in young to middle-aged adults.

Tagged: alzheimer disease, association, deficiency, gastritis, gondii infection, health, impairment, performance, united-states, us adults

Cognitive functions

Toxoplasma gondii impairs memory in infected seniors

October 10, 2014
Gajewski, P. D., Falkenstein, M., Hengstler, J. G., Golka, K.
Brain Behavior and Immunity 2014; 36: 193-199

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lmost 30% of humans present a Toxoplasma gondii positive antibody status and its prevalence increases with age. The central nervous system is the main target. However, little is known about the influence of asymptomatic i.e. latent Toxoplasmosis on cognitive functions in humans. To investigate neurocognitive dysfunctions in asymptomatic older adults with T. gondii positive antibody status a double-blinded neuropsychological study was conducted. The participants were classified from a population-based sample (N = 131) of healthy participants with an age of 65 years and older into two groups with 42 individuals each: Toxoplasmosis positive (T-pos; IgG > 50 IU/ml) and Toxoplasmosis negative (T-neg; IgG = 0 IU/ml). The outcome measures were a computer-based working-memory test (2-back) and several standardized psychometric tests of memory and executive cognitive functions. T-pos seniors showed an impairment of different aspects of memory. The rate of correctly detected target symbols in a 2-back task was decreased by nearly 9% (P = 0.020), corresponding to a performance reduction of about 35% in working memory relative to the T-neg group. Moreover, T-pos seniors had a lower performance in a verbal memory test, both regarding immediate recall (10% reduction; P = 0.022), delayed recognition (6%; P = 0.037) and recall from long-term memory assessed by the word fluency tests (12%; P = 0.029). In contrast, executive functions were not affected. The effects remained mostly unchanged after controlling for medication. The impairment of memory functions in T-pos seniors was accompanied by a decreased self-reported quality of life. Because of the high prevalence of asymptomatic Toxoplasmosis and an increasing population of older adults this finding is of high relevance for public health

Tagged: age, aging, behavior, challenges, cognition, Dopamine, humans, load, memory, performance, rats, task, Toxoplasma gondii, vaccines, working memory

Cognitive functions

Toxoplasma gondii exposure affects neural processing speed as measured by acoustic startle latency in schizophrenia and controls

October 10, 2013
Pearce, B. D., Hubbard, S., Rivera, H. N., Wilkins, P. P., Fisch, M. C., Hopkins, M. H., Hasenkamp, W., Gross, R., Bliwise, N., Jones, J. L., Duncan, E.
Schizophrenia Research 2013; 150: 258-261

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The prevalence of Toxoplasma gondii (TOXO) infection in schizophrenia (SCZ) is elevated compared to controls (odds ratio = 2.73). TOXO infection is associated with psychomotor slowing in rodents and non-psychiatric humans. Latency of the acoustic startle response, an index of neural processing speed, is the time it takes for a startling stimulus to elicit the reflexive response through a three-synapse subcortical circuit. We report a significant slowing of latency in TOXO seropositive SCZ vs. seronegative SCZ, and in TOXO seropositive controls vs. seronegative controls. Latency was likewise slower in SCZ subjects than in controls. These findings indicate a slowing of neural processing speed with chronic TOXO infection; the slowest startle latency was seen in the TOXO seropositive SCZ group

Tagged: acoustic startle, deficits, habituation, infection, latency, normals, performance, prepulse inhibition, rats, reflex, rodents, Schizophrenia, Toxoplasma gondii, traffic accidents

Behavior Cognitive functions Motor functions

Look what the cat dragged in: do parasites contribute to human cultural diversity?

October 30, 2005
Lafferty, K.D.
Behavioural Processes 2005; 68: 279-282

Tagged: behavior, cats, culture, mice, performance, personality, rats, rattus-norvegicus, Toxoplasma gondii, toxoplasma gondii infection

Behavior Personality

Toxoplasma gondii & Human Phenotype

Compendium of Known Effects and Ongoing Research

performance

The potential risk of toxoplasmosis for traffic accidents: A systematic review and meta-analysis

Association between latent toxoplasmosis and cognition in adults: a cross-sectional study

Toxoplasma gondii seropositivity and cognitive functions in school-aged children

Interaction between Helicobacter pylori and latent toxoplasmosis and demographic variables on cognitive function in young to middle-aged adults

Toxoplasma gondii impairs memory in infected seniors

Toxoplasma gondii exposure affects neural processing speed as measured by acoustic startle latency in schizophrenia and controls

Look what the cat dragged in: do parasites contribute to human cultural diversity?