In December 2019, the first reports came from China about cases of pneumonia caused by a previously unknown coronavirus, SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2), responsible for a disease called COVID-19. Since then, the pandemic has spread worldwide, affecting people’s physical and mental health and as well as quality of life. Currently, many people are experiencing the health consequences of contracting COVID-19, also due to the impact this disease has on the central nervous system. As a result, in addition to well-known ailments, such as headaches, chronic fatigue or smell and taste disorders, COVID-19 survivors may develop neuropsychological problems such as executive-attentional deficits. However, the specificity of these executive-attentional problems has not been determined. Thus, the purpose of this study was to learn if survivors of COVID-19 may present with more generalized or rather specific dysfunction(s) of the anterior attentional-executive system.

The study group consisted of 37 individuals who underwent COVID-19 (age M=44, education M=17). The comparison group consisted of 25 matched controls tested before the COVID-19 pandemia. The experimental procedures included (1) a clinical interview, (2) an assessment of selected cognitive functions (3) and attentionalexecutive functioning, which was assessed using the ROtman-Baycrest Battery to Investigate Attention (ROBBIA); a battery was designed to measure three attentional processes (i.e., energizing, task setting, and monitoring). Overall, four reaction time (RT) subtests from ROBBIA were administered: (1) Simple RT, (2) Choice RT, (3), Prepare RT, and (4) Concentrate. For each subtest, the instruction was to press an appropriate button on a response pad as quickly as possible when a target stimulus (one of the following capital letters: A, B, C, or D) is detected, but also (in Choice RT, Prepare RT and Concentrate) to make as few errors as possible.

Overall, the analyses revealed that individuals who survived COVID-19 exhibited a different effect of the warning stimulus compared to controls. Specifically, COVID19 survivors presented an increase in reaction time from 1s warning condition to 3s warning condition being significantly greater than the control group’s increase (p < .05). Also, only in the COVID-19 group, reaction time in the Concentrate task tended to be longer (p = 0.01). No group differences in monitoring (e.g., number of errors) or task setting emerged.

The patients’ problems appear analogous to those observed in other chronic somatic diseases, likely due to the impact of COVID-19 on the frontal lobe’s medial regions. However, due to a small sample size, future neuroimaging research, including computerized studies of attentional-execution networks, is needed to confirm that COVID-19 may predominantly affect the energization system that contributes to these patient’s cognitive slowing and defective ability to sustain attention.

Set-shifting/switching tasks, among other measures of executive functioning, are typically thought to represent frontal lobe functioning. However, the neuroanatomical correlates of these tests are not fully established. The aim of this study was to examine associations between individual measures of set-shifting/switching and cortical thickness. We hypothesized that performance on each switching measure would strongly correlate with aggregated cortical thickness within the frontal lobe.

Measures of interest included set-shifting subtests of the Delis-Kaplan Executive Function System (DKEFS): Color-Word Inhibition Switching, Category Switching, and Trail Making Test Number-Letter Switching. Archival data from an outpatient memory disorders clinic were reviewed to identify individuals whose neuropsychological evaluations included the measures of interest and had quality-assessed, volumetric MRI data available (n=243; 53.1% male, 81.9% Caucasian, Mage=72.4, SDage=6.7). Cortical thickness values were generated by FreeSurfer and averages were calculated for both frontal and temporal lobes, separately. Using partial correlations, controlling for age, we explored associations between each switching trial separately with right and left, frontal and temporal cortical thickness. The strength of associations within each lobe were then compared using Fisher's r-to-z transformations.

Category Switching was significantly correlated with left and right hemisphere temporal thickness (r=0.38 and 0.31, respectively), but was not significantly correlated with left or right frontal lobe cortical thickness (r=.12 and .07, respectively). Fisher's r-to-z transformations revealed significantly stronger relationships between Category Switching and temporal thickness, rather than frontal thicknesses. Trails Switching was also significantly correlated with left and right temporal cortical thickness (r=-0.28, and =-0.23, respectively) and bore weaker associations with frontal cortical thickness (r=-.13 and r = -.14 for left and right hemispheres, respectively). In contrast, Color-Word Inhibition-Switching did not show a significant relationship with frontal or temporal cortical thickness.

Contrary to our hypothesis, stronger associations were observed with temporal lobe cortical thickness for Category Switching. Category Switching involves a language production component which could explain the strong association with temporal cortical thickness compared to frontal cortical thickness. Additionally, the pattern of associations between Trails Switching and frontal and temporal thickness was non-specific. Perhaps most striking is the lack of association between each switching measure and frontal cortical thickness, which was unexpected, given that these measures are used to assess executive functioning, broadly localized to the frontal lobe. Future directions involve examining the associations of these measure with subcortical structures and replicating these findings in larger datasets.

The purpose of this investigation was to examine neuropsychological functioning after frontal (FL) or temporal lobectomy (ATL) in patients with localization related epilepsy. Few studies have compared cognitive changes following FL and ATL. Past research found improvement on measures of verbal and visual memory along with confrontation naming after FL (Busch et al., 2017). In contrast, a number of studies have reported verbal memory and naming decline in those undergoing left ATL. The current study examined post-operative cognitive changes in epilepsy patients who underwent either a left or right FL or ATL.

Subjects include 430 patients (204 men, 225 women, 1 gender not specified), who underwent surgical resection; Right FL = 25, Left FL = 26, Right ATL = 211, Left ATL = 168. Patients had a mean FSIQ = 90, ages ranging from 18 to 71 (mean age = 37 years), right (n=359), left (n=50), or mixed (n=18) handedness, and education ranging from 3 to 22 years (mean = 12.9 years of education). Change from pre- to post FL and ATL was examined in the following domains: learning and memory [Long Term Storage for Selective Reminding Tests (SRT), Wechsler’s Memory Scale (WMS): Logical Memory Delayed Recall (LM) and Visual Reproduction Delayed Recall (VR)], and language [Boston Naming Test (BNT)].

A one-way ANOVA was used to examine changes in language and memory. Our findings revealed statistically significant differences between resection groups for LM, SRT, and BNT. There were significant declines (p<.001) for left ATL when compared to right ATL for LM, SRT, and BNT. There were significant declines for left ATL, when compared to the gains in both left (p<.001; p=.002) and right (p=.018; p=.008) FL for LM and BNT. Left ATL also had significant declines when compared to gains in SRT (p<.001) for right FL. There were significant declines for left FL when compared to right ATL for SRT (p=.007). Lastly, there were significant gains for right FL when compared to left FL for SRT (p=.020).

The pre- to post-surgical neuropsychological change in learning, memory, and language is understudied in frontal lobe epilepsy (FLE); although several investigators reported some learning and memory impairments in FLE at either pre- or post-surgical time points (Johnson-Markve et al., 2011; Incisa Della Rocchetta et al., 1993). The current study suggests that resections of the frontal lobes are associated with better outcomes for naming and verbal memory (LM) when compared to left ATLs. Interestingly, verbal list learning declined more in left than right FL and right ATL patients suggesting a possible language based executive functioning component to this memory measure. As expected, our study further supports that left ATLs are associated with material specific memory declines. This pattern was not seen for those undergoing a right ATL (i.e., nonverbal memory did not decline in patients with right ATL).

The brain is reliant on mitochondria to carry out a host of vital cellular functions (e.g., energy metabolism, respiration, apoptosis) to maintain neuronal integrity. Clinically relevant, dysfunctional mitochondria have been implicated as central to the pathogenesis of Alzheimer’s disease (AD). Phosphorous magnetic resonance spectroscopy (31p MRS) is a non-invasive and powerful method for examining in vivo mitochondrial function via high energy phosphates and phospholipid metabolism ratios. At least one prior 31p MRS study found temporal-frontal differences for high energy phosphates in persons with mild AD. The goal of the current study was to examine regional (i.e., frontal, temporal) 31p MRS ratios of mitochondrial function in a sample of older adults at-risk for AD. Given the high energy consumption in temporal lobes (i.e., hippocampus) and preferential age-related changes in frontal structure-function, we predicted 31p MRS ratios of mitochondrial function would be greater in temporal as compared to frontal regions.

The current study leveraged baseline neuroimaging data from an ongoing multisite study at the University of Florida and University of Arizona. Participants were older adults with memory complaints and a first-degree family history of AD [N = 70; mean [M] age [years] = 70.9, standard deviation [SD] =5.1; M education [years] = 16.2, SD = 2.2; M MoCA = 26.5, SD = 2.4; 61.4% female; 91.5% non-latinx white]. To achieve optimal sensitivity, we used a single voxel method to examine 31p MRS ratios (bilateral prefrontal and left temporal). Mitochondrial function was estimated by computing 5 ratios for each voxel: summed adenosine triphosphate to total pooled phosphorous (ATP/TP; momentary energy), ATP to inorganic phosphate (ATP/Pi; energy consumption), phosphocreatine to ATP (PCr/ATP; energy reserve), phosphocreatine to inorganic phosphate (PCr/Pi; oxidative phosphorylation), and phosphomonoesters to phosphodiesters (PME/PDE; cellular membrane turnover rate). All ratios were corrected for voxel size and cerebrospinal fluid fraction. Separate repeated measures analyses of variance controlling for scanner site differences (RM ANCOVAs) were performed.

31p MRS ratios were unrelated to demographic characteristics and were not included as additional covariates in analyses. Results of separate RM ANCOVAs revealed all 31p MRS ratios of mitochondrial function were greater in left temporal relative to bilateral prefrontal voxel: ATP/TP (p < .001), ATP/Pi (p = .001), PCr/ATP (p = .004), PCr/Pi (p = .004), and PME/PDE (p = .017). Effect sizes (partial eta squared) ranged from 0.6-.20.

Consistent and extending one prior study, all 31p MRS ratios of mitochondrial function were greater in temporal as compared to frontal regions in older adults at-risk for AD. This may in part be related to the intrinsically high metabolic rate of the temporal region and preferential age-related changes in frontal structure-function. Alternatively, findings may reflect the influence of unaccounted factors (e.g., hemodynamics, auditory stimulation). Longitudinal study designs may inform whether patterns of mitochondrial function across different brain regions are present early in development, occur across the lifespan, or some combination. In turn, this may inform future studies examining differences in mitochondrial function (as measured using 31p MRS) in AD.

A high proportion of patients with remitted major depressive disorder (MDD) will experience recurring episodes, whilst some develop resilience and remain in recovery. The neural basis of resilience to recurrence is elusive. Abnormal resting-state connectivity of the subgenual cingulate cortex (sgACC) was previously found in cross-sectional studies of MDD, suggesting its potential pathophysiological importance. The current study aimed to investigate whether resting-state connectivity to a left sgACC seed region distinguishes resilient patients from those developing recurring episodes.

A total of 47 medication-free remitted MDD patients and 38 healthy controls underwent resting-state functional magnetic resonance imaging (fMRI) at baseline. Over 14 months, 30 patients remained resilient whilst 17 experienced a recurring episode.

Attenuated interhemispheric left-to-right sgACC connectivity distinguished the resilient from the recurring-episode and control groups and was not correlated with residual depressive symptoms.

The current study revealed a neural signature of resilience to recurrence in MDD and thereby elucidates the role of compensatory adaptation in sgACC networks.

Relatively lower executive functioning is characteristic of individuals with schizophrenia. As low socio-economic status (SES) early in life (i.e. parent SES) has been linked with lower executive skills in healthy children, we hypothesized that parental SES (pSES) would be more strongly related to executive functioning in individuals with schizophrenia than in controls and have a greater impact on prefrontal cortical morphology.

Healthy controls (n = 125) and individuals with schizophrenia (n = 102) completed tests assessing executive functioning and intelligence. The groups were matched on pSES, which was evaluated with the Hollingshead–Redlich scale. A principal components analysis (PCA) was conducted on 10 variables from six executive tests, yielding three specific components (fluency, planning and response inhibition). Voxel-based morphometry (VBM) was used to evaluate effects of pSES on gray matter (GM) concentration.

Lower pSES was associated with lower scores across the three executive functioning components, and a significant group by pSES interaction was observed such that low pSES, in particular, affected individuals with schizophrenia. These effects remained significant when intellectual ability, education and self-SES (sSES) were added as covariates. VBM revealed that lower pSES was associated with reduced GM volume in several anterior brain regions, especially the superior frontal gyrus, in patients but not in controls.

These findings suggest that individuals with schizophrenia may be particularly vulnerable to the adverse impact of low pSES, in terms of both lower executive skills and reduced anterior GM volumes.

Interest in the neuro-cognitive profile of patients with schizophrenia and co-morbid obsessive compulsive disorder (schizo-OCD) is rising in response to reports of high co-morbidity rates. Whereas schizophrenia has been associated with global impairment in a wide range of neuro-cognitive domains, OCD is associated with specific deficits featuring impaired performance on tasks of motor and cognitive inhibition involving frontostriatal neuro-circuitry.

We compared cognitive function using the CANTAB battery in patients with schizo-OCD (n=12) and a schizophrenia group without OCD symptoms (n=16). The groups were matched for IQ, gender, age, medication, and duration of illness.

The schizo-OCD patients made significantly more errors on a task of attentional set-shifting (ID-ED set-shift task). By contrast, no significant differences emerged on the Stockings of Cambridge task, the Cambridge Gamble Task or the Affective Go/NoGo tasks. No correlation emerged between ID-ED performance and severity of schizophrenia, OCD or depressive symptoms, consistent with neurocognitive impairment holding trait rather than state-marker status. Schizo-obsessives also exhibited a trend toward more motor tics emphasizing a neurological contribution to the disorder.

Our findings reveal a more severe attentional set-shifting deficit and neurological abnormality that may be fundamental to the neuro-cognitive profile of schizo-OCD. The clinical implications of these impairments merit further exploration in larger studies.