News and Commentary Archive

Explore recent scientific discoveries and news as well as CLBB events, commentary, and press.

Mission

The speed of technology in neuroscience as it impacts ethical and just decisions in the legal system needs to be understood by lawyers, judges, public policy makers, and the general public. The Massachusetts General Hospital Center for Law, Brain, and Behavior is an academic and professional resource for the education, research, and understanding of neuroscience and the law. Read more

Social Cognition Over Time in Individuals at Clinical High Risk for Psychosis: Findings from the NAPLS-2 Cohort

By Danijela Piskulic, Lu Liu, Kristin S. Cadenhead, Tyrone D. Cannon, Barbara A. Cornblatt, Thomas H. McGlashan, Diana O. Perkins, Larry J. Seidman, Ming T. Tsuang, Elaine F. Walker, Scott W. Woods, Carrie E. Bearden, Daniel H. Mathalon, and Jean Addington | Schizophrenia Research | January 16, 2016

Abstract:

Deficits in social cognition are well established in schizophrenia and have been observed prior to the illness onset. Compared to healthy controls (HCs), individuals at clinical high risk of psychosis (CHR) are said to show deficits in social cognition similar to those observed in patients experiencing a first episode of psychosis. These deficits have been observed in several domains of social cognition, such as theory of mind (ToM), emotion perception and social perception. In the current study, the stability of three domains of social cognition (ToM, social perception and facial emotion perception) was assessed over time along and their association with both clinical symptoms and the later development of psychosis. Six hundred and seventy-five CHR individuals and 264 HC participants completed four tests of social cognition at baseline. Of those, 160 CHR and 155 HC participants completed assessments at all three time points (baseline, 1 year and 2 years) as part of their participation in the North American Prodrome Longitudinal Study. The CHR group performed poorer on all tests of social cognition across all time points compared to HCs. Social cognition was not associated with attenuated positive symptoms at any time point in the study. CHR individuals who developed a psychotic disorder during the course of the study did not differ in social cognition compared to those who did not develop psychosis. This longitudinal study demonstrated mild to moderate, but persistent ToM and social perception impairments in those at CHR for psychosis compared to HCs.

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Alterations of Lateral Temporal Cortical Gray Matter and Facial Memory as Vulnerability Indicators for Schizophrenia: An MRI Study in Youth at Familial High-Risk for Schizophrenia

By Benjamin K. Brent, Isabelle M. Rosso, Heidi W. Thermenos, Daphne J. Holt, Stephen V. Faraone, Nikos Makris, Ming T. Tsuang, and Larry J. Seidman | Schizophrenia Research | November 24, 2015

Abstract:

Background

Structural alterations of the lateral temporal cortex (LTC) in association with memory impairments have been reported in schizophrenia. This study investigated whether alterations of LTC structure were linked with impaired facial and/or verbal memory in young first-degree relatives of people with schizophrenia and, thus, may be indicators of vulnerability to the illness.

Methods

Subjects included 27 non-psychotic, first-degree relatives of schizophrenia patients, and 48 healthy controls, between the ages of 13 and 28. Participants underwent high-resolution magnetic resonance imaging (MRI) at 1.5 Tesla. The LTC was parcellated into superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus, and temporal pole. Total cerebral and LTC volumes were measured using semi-automated morphometry. The Wechsler Memory Scale — Third Edition and the Children’s Memory Scale — Third Edition assessed facial and verbal memory. General linear models tested for associations among LTC subregion volumes, familial risk and memory.

Results

Compared with controls, relatives had significantly smaller bilateral middle temporal gyri. Moreover, right middle temporal gyral volume showed a significant positive association with delayed facial memory in relatives.

Conclusion

These results support the hypothesis that smaller middle temporal gyri are related to the genetic liability to schizophrenia and may be linked with reduced facial memory in persons at genetic risk for the illness. The findings add to the growing evidence that children at risk for schizophrenia on the basis of positive family history have cortical and subcortical structural brain abnormalities well before psychotic illness occurs.

Read the full article here.

Evaluating the Relationship between Cannabis Use and IQ in Youth and Young Adults at Clinical High Risk of Psychosis

By Lisa Buchy, Larry J. Seidman, Kristin S. Cadenhead, Tyrone D. Cannon, Barbara A. Cornblatt, Thomas H. McGlashan, Diana O. Perkins, William Stone, Ming T. Tsuang, Elaine F. Walker, Scott W. Woods, Carrie E. Bearden, Daniel H. Mathalon, and Jean Addington | Psychiatry Research | November 20, 2015

Abstract:

Among people with psychosis, those with a history of cannabis use show better cognitive performance than those who are cannabis naïve. It is unknown whether this pattern is present in youth at clinical high risk (CHR) of psychosis. We evaluated relationships between IQ and cannabis use while controlling for use of other substances known to impact cognition in 678 CHR and 263 healthy control (HC) participants. IQ was estimated using the Vocabulary and Block Design subtests of the Wechsler Abbreviated Scale of Intelligence. Drug and alcohol use severity and frequency were assessed with the Alcohol and Drug Use Scale, and we inquired participants’ age at first use. CHR were further separated into early and late age at onset of cannabis use sub-groups, and low-, moderate- and high-frequency sub-groups. No significant differences in IQ emerged between CHR or HC cannabis users vs. non-users, or between use frequency groups. CHR late-onset users showed significantly higher IQ than CHR early-onset users. Age at onset of cannabis use was significantly and positively correlated with IQ in CHR only. Results suggest that age at onset of cannabis may be a more important factor for IQ than use current use or use frequency in CHR.

Read the entire paper here.

A New MRI Masking Technique Based on Multi-Atlas Brain Segmentation in Controls and Schizophrenia: A Rapid and Viable Alternative to Manual Masking

By Elisabetta C. del Re, Yi Gao, Ryan Eckbo, Tracey L. Petryshen, Gabriëlla A.M. Blokland, Larry J. Seidman, Jun Konishi, Jill M. Goldstein, Robert W. McCarley, Martha E. Shenton, and Sylvain Bouix | Journal of Neuroimaging | November 20, 2015

Abstract:

Brain masking of MRI images separates brain from surrounding tissue and its accuracy is important for further imaging analyses. We implemented a new brain masking technique based on multi-atlas brain segmentation (MABS) and compared MABS to masks generated using FreeSurfer (FS; version 5.3), Brain Extraction Tool (BET), and Brainwash, using manually defined masks (MM) as the gold standard. We further determined the effect of different masking techniques on cortical and subcortical volumes generated by FreeSurfer.

METHODS

Images were acquired on a 3-Tesla MR Echospeed system General Electric scanner on five control and five schizophrenia subjects matched on age, sex, and IQ. Automated masks were generated from MABS, FS, BET, and Brainwash, and compared to MM using these metrics: a) volume difference from MM; b) Dice coefficients; and c) intraclass correlation coefficients.

RESULTS

Mean volume difference between MM and MABS masks was significantly less than the difference between MM and FS or BET masks. Dice coefficient between MM and MABS was significantly higher than Dice coefficients between MM and FS, BET, or Brainwash. For subcortical and left cortical regions, MABS volumes were closer to MM volumes than were BET or FS volumes. For right cortical regions, MABS volumes were closer to MM volumes than were BET volumes.

CONCLUSIONS

Brain masks generated using FreeSurfer, BET, and Brainwash are rapidly obtained, but are less accurate than manually defined masks. Masks generated using MABS, in contrast, resemble more closely the gold standard of manual masking, thereby offering a rapid and viable alternative.

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Cognitive Ability in Childhood and the Chronicity and Suicidality of Depression

By Galen Chin-Lun Hung, Stefanie A. Pietras, Hannah Carliner, Laurie Martin, Larry J. Seidman, Stephen L. Buka, and Stephen E. Gilman | The British Journal of Psychiatry | November 2015

Abstract:

Background

There is inconsistent evidence regarding the influence of general cognitive abilities on the long-term course of depression.

Aims

To investigate the association between general childhood cognitive abilities and adult depression outcomes.

Method

We conducted a cohort study using data from 633 participants in the New England Family Study with lifetime depression. Cognitive abilities at age 7 were measured using the Wechsler Intelligence Scale for Children. Depression outcomes were assessed using structured diagnostic interviews administered up to four times in adulthood between ages 17 and 49.

Results

In analyses adjusting for demographic factors and parental psychiatric illness, low general cognitive ability (i.e. IQ<85 v. IQ>115) was associated with recurrent depressive episodes (odds ratio (OR) = 2.19, 95% CI 1.20–4.00), longer episode duration (rate ratio 4.21, 95% CI 2.24–7.94), admission to hospital for depression (OR = 3.65, 95% CI 1.34–9.93) and suicide ideation (OR = 3.79, 95% CI 1.79–8.02) and attempt (OR = 4.94, 95% CI 1.67–14.55).

Conclusions

Variation in cognitive abilities, predominantly within the normal range and established early in childhood, may confer long-term vulnerability for prolonged and severe depression. The mechanisms underlying this vulnerability need to be established to improve the prognosis of depression among individuals with lower cognitive abilities.

Read the full article here.