Multiphasic value biases in fast-paced decisions.

Perceptual decisions are biased toward higher-value options when overall gains can be improved. When stimuli demand immediate reactions, the neurophysiological decision process dynamically evolves through distinct phases of growing anticipation, detection, and discrimination, but how value biases are exerted through these phases remains unknown. Here, by parsing motor preparation dynamics in human electrophysiology, we uncovered a multiphasic pattern of countervailing biases operating in speeded decisions. Anticipatory preparation of higher-value actions began earlier, conferring a 'starting point' advantage at stimulus onset, but the delayed preparation of lower-value actions was steeper, conferring a value-opposed buildup-rate bias. This, in turn, was countered by a transient deflection toward the higher-value action evoked by stimulus detection. A neurally-constrained process model featuring anticipatory urgency, biased detection, and accumulation of growing stimulus-discriminating evidence, successfully captured both behavior and motor preparation dynamics. Thus, an intricate interplay of distinct biasing mechanisms serves to prioritise time-constrained perceptual decisions.

Contralateral delay activity is not a robust marker of cognitive function in older adults at risk of mild cognitive impairment.

Contralateral delay activity (CDA) has been proposed as a pre-clinical neural marker for mild cognitive impairment (MCI). However, existing evidence is limited to one study with a small sample size (n = 24). Our aim was to extend previous work by investigating the relationship between the CDA and MCI risk in a large sample of older adults (n = 76). We used a regression approach to determine whether (and when) CDA amplitude predicted MCI risk, as indexed by the Montreal Cognitive Assessment (MoCA). CDA amplitude from ~300-500 and ~800-900 ms predicted MoCA performance. However, significant effects were only observed for specific electrodes (P5/P6 and CP3/CP4, but not PO7/PO8) and the nature of the relationship between the CDA and MoCA scores differed across time and according to set size. Bayesian regression analysis indicated partial evidence in favour of the null hypothesis (BF10 values = 4-1.18). Contrary to previous results, our findings suggest that the CDA may not a robust marker of MCI risk. More broadly, our results highlight the difficulty in identifying at-risk individuals, particularly as MCI is a heterogeneous, unstable condition. Future research should prioritise longitudinal approaches in order to track the progression of the CDA and its association with cognitive decline in later life.

Mood matters: a national survey on attitudes to depression.

BACKGROUND: Depression is the leading contributor to the burden of disease worldwide. Stigma and negative attitudes to depression can act as barriers to treatment and to social inclusion. Understanding attitudes to depression and treatment has implications for individual outcomes and societal mental health. AIMS: To explore public attitudes to, and management of depression, including lifestyle factors, medication, and psychotherapy. METHODS: A nationally representative online population survey of Irish adults was conducted by RED C. RESULTS: Nine hundred ninety-one people completed the survey. The majority thought that depression was a medical illness (90%), was different to sadness or stress (89%), and that awareness of depression was increasing (89%), while stigma was reducing (69%). Self-reported lifetime depression rates were high and were significantly higher in younger people (18-34 yrs) (63% vs 55%, p = 0.017), and in urban areas (60% vs 44%, p < 0.0001). Younger people were less likely to contact their GP (46% vs 61%, p = 0.034) and reported more stigma around antidepressants (ADTs) compared to older people (> 55 years) (74% vs 58%, p < 0.0001). There were negative attitudes to ADTs and a preference for talking therapies and lifestyle changes. Males were more likely to hold negative attitudes to ADTs. CONCLUSIONS: Stigma around depression is reducing and public awareness is improving. However, the very high self-reported lifetime rates of depression may reflect milder forms or emotional/psychological distress, rather than clinical depression. Negative attitudes and stigma towards ADTs remains high. A collaborative, sustained effort is required to advance public appreciation of mood and its management, across the severity spectrum, in tandem with destigmatising the targeted use of ADTs.