Decreased reward-related brain function prospectively predicts increased substance use

Substance use and addiction are prominent global health concerns and are associated with abnormalities in reward sensitivity. Reward sensitivity and approach motivation are supported by a fronto-striatal neural circuit including the orbitofrontal cortex (OFC), ventral striatum (VS), and dorsal striatum (DS). Although research highlights abnormalities in reward neural circuitry among individuals with problematic substance use, questions remain about whether such use arises from excessively high, or excessively low, reward sensitivity. This study examined whether reward-related brain function predicted subsequent substance use course. Participants were 79 right-handed individuals (Mage = 21.52, SD = 2.19 years), who completed a monetary incentive delay (MID) fMRI task, and follow-up measures assessing substance use frequency and impairment. The average duration of the follow-up period was 9.1 months. Regions-of-interest analyses focused on the reward anticipation phase of the MID. Decreased activation in the VS during reward anticipation predicted increased substance use frequency at follow-up. Decreased DS activation during reward anticipation predicted increased substance use frequency at follow-up, but this finding did not pass correction for multiple comparisons. Analyses adjusted for relevant covariates, including baseline substance use and the presence or absence of a lifetime substance use disorder prior to MRI scanning. Results support the reward hyposensitivity theory, suggesting that decreased reward-related brain function is a risk factor for increased substance use. Results have implications for understanding the pathophysiology of problematic substance use and highlight the importance of the fronto-striatal reward circuit in the development and maintenance of addiction. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Motor abnormalities, depression risk, and clinical course in adolescence

Background

Motor abnormalities, such as psychomotor agitation and retardation, are widely recognized as core features of depression. However, it is not currently known if motor abnormalities connote risk for depression.

Methods

Using data from the Adolescent Brain Cognitive Development (ABCD) Study, a nationally representative sample of youth (n=10,835, 9-11 years old), the present paper examines whether motor abnormalities are associated with (a) depression symptoms in early adolescence, (b) familial risk for depression (familial risk loading), and (c) future depression symptoms. Motor abnormalities measures included traditional (DSM) motor signs such as psychomotor agitation and retardation as well as other motor domains such as developmental motor delays and dyscoordination.

Results

Traditional motor abnormalities were less prevalent (agitation=3.2%, retardation=0.3%) than non-traditional domains (delays=13.79%, coordination=35.5%) among adolescents. Motor dysfunction was associated with depression symptoms (Cohen's ds=0.02 to 0.12). Familial risk for depression was related to motor abnormalities (Cohen's ds=0.08 to 0.27), with the exception of motor retardation. Family vulnerability varied in sensitivity to depression risk (e.g., retardation: .53%; dyscoordination: 32.05%). Baseline endorsement of motor abnormalities predicted future depression symptoms at one-year follow-up.

Conclusions

These findings suggest that motor signs reflect a novel, promising future direction for examining vulnerability to depression risk in early adolescence.

Chickens' growth performance and pancreas development exposed to soy cake varying in trypsin inhibitor activity, heat-degraded lysine concentration, and protein solubility in potassium hydroxide

This study focused on the effect of varying trypsin inhibitor activity (TIA), heat-degraded lysine concentration and protein solubility in potassium hydroxide on broiler performance and pancreas weight. Two soybean breeds were subject to varying thermal, hydrothermal, pressure, and kilning processing. This resulted in a total of 34 soy cake variants, widely varying in TIA (0.25 to 23.6 mg/g), heat-degraded lysine (1.40 to 8.60 g/kg), and potassium hydroxide (65.5 to 97.6%), respectively. These soy cake variants as well as a commercial soybean meal extract were included into a common grower and finisher diet for broiler chicks at fixed amounts (grower: 35%; finisher: 25%) and tested in a 35 d fattening experiment with 1680 broiler chicks (grower phase: day 11 to 24; finisher phase day 25 to 35). TIA was the dominant factor affecting zootechnical performance and pancreas weight at slaughter (day 35), depressing liveweight at day 24 (P < 0.006), and day 35 (0.026), weight gain (grower: P < 0.006) and feed: gain ratio during grower phase (P < 0.005) and increasing pancreas weight (P < 0.010) at the time of slaughter. Negative effects of TIA were also visible in soy cake variants below recommended thresholds. This highlights the necessity of complete elimination of TIA in broiler diets as far as technically possible.

Timing dysfunction and cerebellar resting state functional connectivity abnormalities in youth at clinical high-risk for psychosis

BACKGROUND

Consistent with pathophysiological models of psychosis, temporal disturbances in schizophrenia spectrum populations may reflect abnormal cortical (e.g. prefrontal cortex) and subcortical (e.g. striatum) cerebellar connectivity. However, few studies have examined associations between cerebellar connectivity and timing dysfunction in psychosis populations, and none have been conducted in youth at clinical high-risk (CHR) for psychosis. Thus, it is currently unknown if impairments in temporal processes are present in CHR youth or how they may be associated with cerebellar connectivity and worsening of symptoms.

METHODS

A total of 108 (56 CHR/52 controls) youth were administered an auditory temporal bisection task along with a resting state imaging scan to examine cerebellar resting state connectivity. Positive and negative symptoms at baseline and 12 months later were also quantified.

RESULTS

Controlling for alcohol and cannabis use, CHR youth exhibited poorer temporal accuracy compared to controls, and temporal accuracy deficits were associated with abnormal connectivity between the bilateral anterior cerebellum and a right caudate/nucleus accumbens striatal cluster. Poor temporal accuracy accounted for 11% of the variance in worsening of negative symptoms over 12 months.

CONCLUSIONS

Behavioral findings suggest CHR youth perceive durations of auditory tones as shortened compared to objective time, which may indicate a slower internal clock. Poorer temporal accuracy in CHR youth was associated with abnormalities in brain regions involved in an important cerebellar network implicated in prominent pathophysiological models of psychosis. Lastly, temporal accuracy was associated with worsening of negative symptoms across 12 months, suggesting temporal dysfunction may be sensitive to illness progression.

Fasting metabolic rate in hens. 1. Effects of body weight, feather loss, and activity

Environmental factors affecting fasting metabolic rate (FMR) were quantified and a short-time recording system was developed. Discontinuous measurements of gas exchange of 1,120 medium weight brown egg layers were taken after 24 and 36 hr of starvation. Body weight (BW) and shank length (SL) were measured and feather cover and activity evaluated by scores. The FMR increased with deterioration of plumage cover. Differences between hens with complete feather cover (Score 1) and nearly naked birds (Score 4) were 8 kJ2/hr at night and 11 kJ/hr during the light phase. Fully fed hens measured during the light phase showed the same curvilinear relationship as starved birds. Only a small proportion of the heat increment generated by ingested food is used by poorly feathered hens to maintain body temperature. Gaseous exchange was affected by locomotor activity in the respiration chamber. The FMR of resting and quietly standing birds were 29.75 +/- 1.00 kJ/hr and 30.55 +/- 1.00 kJ/hr, respectively. During the prelaying phase, FMR showed an increment of 13 kJ/hr with a peak shortly before oviposition. The following exponential relationships between BW in kilograms, and SL in centimeters with FMR were estimated for light phase FMR = 18.52 BW .59 +/- .05 kJ/hr, R2 = .11; for dark phase FMR = 15.21 BW 54 +/- .04 kJ/hr, R2 = .17 and FMR = .32 SL 1.64 +/- .10 kJ/hr, R2 = .19. In poorly feathered strains, SL was as good a predictor of body size as BW. Correcting FMR data for feather loss changed regression coefficients and allometric functions significantly: for light phase FMR = 15.47 BW .74 +/- .03 kJ/hr and R2 = .15; for dark phase FMR = 13.11 BW .66 +/- .03 kJ/hr and R2 = .28.

Fasting metabolic rate in hens. 2. Strain differences and heritability estimates

Short-term measurements of fasting metabolic rate (FMR) of two medium heavy breeds, Rhode Island Red (RIR), Light Sussex (SS), and their reciprocal crosses, were recorded between 40 and 60 weeks of age. Pure breeds differed significantly in fasting metabolism corrected for body weight, feather loss, and activity. During lighted hours, FMR of RIR exceeded FMR of SS hens by .8 kJ/hr. For the dark period the difference was 1.5 kJ/hr. Fasting metabolic rates of reciprocal crosses fell between parental means. Heterosis in egg mass output of 5 to 6% and 3 to 4% in feed conversion ratio, respectively, did not increase FMR of crosses. Heritability estimates for FMR within stocks were moderately high (FMRD: h2S = .23 to .43). An adjustment for body weight, feather loss, and activity decreased heritabilities, but a genetic component in FMR still persisted (h2S = .05 to .22).

Effects of gradual differences in trypsin inhibitor activity on the estimation of digestible amino acids in soybean expellers for broiler chickens

The present study investigated the effect of varying trypsin inhibitor activity (TIA) in differently processed soybean expellers on apparent prececal amino acid (AA) digestibility in male broiler chickens. Two different raw soybean batches were treated using varying processing techniques and intensities. In this way, 45 expeller extracted soybean meal (ESBM) variants were created. The processed soybean variants were then merged into a basal diet (160 g/kg crude protein [CP]) at 2 inclusion levels (15%, 30%) resulting in 90 different diets plus one basal diet (0.4 mg/g-8.5 mg/g TIA). All diets contained 0.5% titanium dioxide. A total of 5,460-day-old male broilers (Ross 308) were allocated on d 14 to 546 pens (10 birds/pen) after a starter phase (CP 215 g/kg, 14 g/kg Lysine, 12.5 MJ ME/kg). The 91 experimental diets were fed ad libitum until d 22. Subsequently, birds were euthanized and digesta of the terminal ileum was collected for determination of AA digestibility. TIA depressed the prececal digestibility of every single AA significantly in a straight linear fashion (P < 0.001). Sulfur-containing AA expressed the strongest suppression by TIA with cystine showing the lowest apparent prececal digestibility measured (10.6% at 23.6 mg/g TIA in raw ESBM). The present data demonstrate that TIA severely depresses digestibility of essential and nonessential AA in a straight linear fashion. On the one hand, this questions the usefulness of defined upper limits of TIA in soy products whereas on the other hand, TIA must be considered when testing raw components for their feed protein value in vivo.

Differentiating kinds of systemic stressors with relation to psychotic-like experiences in late childhood and early adolescence: the stimulation, discrepancy, and deprivation model of psychosis

INTRODUCTION

Conceptualizations that distinguish systems-level stress exposures are lacking; the Stimulation (lack of safety and high attentional demands), Discrepancy (social exclusion and lack of belonging), and Deprivation (lack of environmental enrichment) (SDD) theory of psychosis and stressors occurring at the systems-level has not been directly tested.

METHODS

Exploratory factor analysis was conducted on 3,207 youth, and associations with psychotic-like experiences (PLEs) were explored.

RESULTS

Though model fit was suboptimal, five factors were defined, and four were consistent with the SDD theory, and related to PLEs. Objective and subjective/self-report exposures for deprivation showed significantly stronger PLE associations compared to discrepancy and objective stimulation factors. Objective and subjective/self-report measures converged overall, though self-report stimulation exhibited a significantly stronger association with PLEs compared to objective stimulation.

DISCUSSION

Considering distinct system-level exposures could help clarify putative mechanisms and psychosis vulnerability. The preliminary approach potentially informs health policy efforts aimed at psychopathology prevention and intervention.

Demand-oriented riboflavin supply of organic broiler using a feed material from fermentation of Ashbya gossypii

Alternatives to riboflavin (vitamin B₂) production by recombinant microorganisms are needed in organic poultry production, but are cost-intensive, so that a demand-oriented riboflavin supply is necessary. Details on the riboflavin requirements of organic poultry are not available. A feed material with high native riboflavin content from fermentation of the filamentous fungus Ashbya gossypii was studied. Two runs with 800 Ranger Gold™ broilers each (40 pens with 20 animals) were conducted. The fattening period was divided into starter (S), grower (G) and finisher (F) stage. In the first run, a basal diet without riboflavin supplementation (NATIVE; 3.27, 3.50 and 3.16 mg riboflavin/kg DM in S, G and F) was compared to diets with supplementation at low (LOW; 5.30, 4.85 and 5.19 mg/kg in S, G and F), medium (MEDIUM; 7.56, 6.88 and 7.56 mg/kg in S, G and F) and high (HIGH; 10.38, 9.14 and 9.93 mg/kg in S, G and F) dosage. In the second run, different combinations of low and medium riboflavin supplementation were used in S, G and F diets: S-LOW (4.50 mg riboflavin/kg DM), G-MEDIUM (6.66 mg/kg), F-MEDIUM (5.71 mg/kg) (Treatment A), S-LOW (4.50 mg riboflavin/kg DM); G-LOW (4.92 mg/kg), F-LOW (4.01 mg/kg) (Treatment B); S-MEDIUM (6.37 mg/kg), G-MEDIUM (7.37 mg/kg), F-MEDIUM (5.07 mg/kg) (Treatment C); S-MEDIUM (6.37 mg/kg), G-LOW (5.28 mg/kg), F-LOW (4.22 mg/kg) (Treatment D). Body weight, feed and water consumption were recorded weekly, health and welfare indicators were scored bi-weekly. Slaughter traits were assessed for five males and females per pen. In the first run, NATIVE animals showed symptoms of riboflavin deficiency and lower live weights in the second week of age. Riboflavin contents of this group were increased to avoid further deficiency and recovery was observed. Feed conversion was better in HIGH (2.07) compared with NATIVE and LOW (2.11). At slaughter, treatments differed neither for foot pad dermatitis nor plumage cleanliness. In the second run, daily weight gains did not differ between treatments in any of the weeks. Feed conversion ranged between 1.99 and 2.04. Riboflavin deficiency was not observed in the second run, while treatment D showed superior economic efficiency. In conclusion, native contents of feed components (3.27 mg/kg DM) were not sufficient to meet the riboflavin demand and a total content of 4.50 mg/kg DM was identified as safe lower threshold. The levels rather according to commercial recommendations were not additionally beneficial to performance and health.

The Interplay between Reward-Relevant Life Events and Trait Reward Sensitivity in Neural Responses to Reward Cues

The reward hypersensitivity model posits that trait reward hypersensitivity should elicit hyper/hypo approach motivation following exposure to recent life events that activate (goal-striving and goal-attainment) or deactivate (goal-failure) the reward system, respectively. To test these hypotheses, eighty-seven young adults with high (HRew) versus moderate (MRew) trait reward sensitivity reported frequency of life events via the Life Event Interview. Brain activation was assessed during the fMRI Monetary Incentive Delay task. Greater exposure to goal-striving events was associated with higher nucleus accumbens (NAc) reward anticipation among HRew participants and lower orbitofrontal cortex (OFC) reward anticipation among MRew participants. Greater exposure to goal-failure events was associated with higher NAc and OFC reward anticipation only among HRew participants. This study demonstrated different neural reward anticipation (but not outcome) following reward-relevant events for HRew versus MRew individuals. Trait reward sensitivity and reward-relevant life events may jointly modulate reward-related brain function, with implications for understanding psychopathology.

[Water supply for Peking ducks--possible alternatives for bathing]

In order to investigate possible advantages of open water drinkers such as troughs and bells in the intensive husbandry of ducks, we evaluated in this study the effect of open water systems on the behavior and health of peking ducks. In this investigation six fattening trials each with 1152 Cherry Valley Peking ducks were analyzed. The average fattening period was 47 to 49 days. The ducks were kept on straw in six standardized compartments each 32 qm with 192 ducks. 25% of the compartment with perforated grid, with one of the tested water systems. In contrast to pens with nipple-drinkers only, the ducks in pens with open water troughs/showers had the opportunity to exhibit their natural drinking behavior and water associated activities in accordance with the animal welfare requirements. In the free-choice pens the open water systems were significantly preferred, and over a 24-hour period the ducks in watering areas with open water troughs showed higher activity. Limiting the access to the open water systems to eight, four or two hours per day led to an increased use per time unit. Ducks with access to nipple drinkers only showed a significantly higher percentage of plugged up nostrils than animals from pens with open water drinkers. Open water drinkers had also a positive impact on the plumage condition.

Physical and Mental Health in Adolescence: Novel Insights from a transdiagnostic examination of FitBit data in the ABCD Study

Adolescence is among the most vulnerable period for the emergence of serious mental illnesses. Addressing this vulnerability has generated interest in identifying markers of risk for symptoms and opportunities for early intervention. Physical fitness has been linked to psychopathology and may be a useful risk marker and target for early intervention. New wearable technology has made assessing fitness behavior more practical while avoiding recall and self-report bias. Still, questions remain regarding the clinical utility of physical fitness metrics for mental health, both transdiagnostically and along specific symptom dimensions. The current study includes 5007 adolescents (ages 10 to 13) who participated in the Adolescent Brain Cognitive Development (ABCD) study and additional sub-study that collected fitness data from wearable technology and clinical symptom measures. Physical fitness metrics included resting heart rate (RHR- an index of cardiovascular health), time spent sedentary (associated with increased inflammation and cardiovascular disease), and time spent in moderate physical activity (associated with increased neurogenesis, neuroplasticity, and healthy neurodevelopment). Self-report clinical symptoms included measures of internalizing symptoms, externalizing symptoms, and psychosis-like experiences - PLE). Increased RHR- lower cardiovascular fitness- related only to greater internalizing symptoms (t = 3.63). More sedentary behavior related to elevated PLE severity (t = 5.49). More moderate activity related to lower PLE (t=-2.69) and internalizing (t=-6.29) symptom severity. Wearable technology fitness metrics linked physical health to specific mental health dimensions, which emphasizes the utility of detailed digital health data as a marker for risk and the need for precision in targeting physical health behaviors to benefit symptoms of psychopathology.