Economic choice options contain multiple components and constitute vectorial bundles. The question arises how they are represented by single-dimensional, scalar neuronal signals that are suitable for economic decision-making. Revealed Preference Theory provides formalisms for establishing preference relations between such bundles, including convenient graphic indifference curves. During stochastic choice between bundles with the same two juice components, we identified neuronal signals for vectorial, multi-component bundles in the orbitofrontal cortex of monkeys. A scalar signal integrated the values from all bundle components in the structured manner of the Theory; it followed the behavioral indifference curves within their confidence limits, was indistinguishable between differently composed but equally revealed preferred bundles, predicted bundle choice and complied with an optimality axiom. Further, distinct signals in other neurons coded the option components separately but followed indifference curves as a population. These data demonstrate how scalar signals represent vectorial, multi-component choice options.

IntroductionTrastuzumab, a recombinant humanized monoclonal antibody, is targeted against the external domain of the human epidermal growth factor receptor type 2 (HER2). It improves efficacy of HER2-positive breast cancer treatment. The authors present their experience with patients (pts) treated with trastuzumab in the aspects of cardiac complications.Material and methodsWe observed prospectively 253 women with early positive HER2 breast cancer treated with trastuzumab. Assessment of cardiovascular status, ECG and echocardiography was performed initially and every 3 months until 6th month during follow-up.ResultsCardiac complications developed in 52 pts (20.55%) and included: asymptomatic left ventricle dysfunction (43), symptomatic heart failure (6), new asymptomatic LBBB (1); new negative T-waves in ECG (2). There was a progressive decline in left ventricular ejection fraction (LVEF) during treatment. It was more enhanced in pts with cardiac complications. Following trastuzumab termination/discontinuation LVEF increased but at month 18 still remained significantly lower than initially in both groups (61.07 ±4.84 vs. 59.97 ±5.23 – no cardiac complications; p < 0.05; 58.14 ±4.08% vs. 53.08 ±5.74% – cardiac complications; p < 0.05). During 6-month follow-up 33 out of 46 pts experienced an improvement in left ventricular status. In 13 pts in whom trastuzumab was discontinued, it was restarted; 6 of them successfully completed total therapy. Univariate analysis revealed no association between any cardiovascular risk factor and the development of cardiotoxicity.ConclusionsOne out of five treated patients discontinues trastuzumab in an adjuvant setting due to cardiac complications. LV dysfunction is the most frequent. Routine cardiac monitoring should be obligatory.

In hypertensive patients, a first-ever ischemic stroke was associated with larger left atrial size, left ventricular mass index and internal carotid artery stenosis. LAVi was the left atrial measurement most closely associated with ischemic stroke.

Frequency modulation (FM) is a common acoustic feature of natural sounds and is known to play a role in robust sound source recognition. Auditory neurons show precise stimulus-synchronized discharge patterns that may be used for the representation of low-rate FM. However, it remains unclear whether this representation is based on synchronization to slow temporal envelope (ENV) cues resulting from cochlear filtering or phase locking to faster temporal fine structure (TFS) cues. To investigate the plausibility of those encoding schemes, single units of the ventral cochlear nucleus of guinea pigs of either sex were recorded in response to sine FM tones centered at the unit's best frequency (BF). The results show that, in contrast to high-BF units, for modulation depths within the receptive field, low-BF units (<4 kHz) demonstrate good phase locking to TFS. For modulation depths extending beyond the receptive field, the discharge patterns follow the ENV and fluctuate at the modulation rate. The receptive field proved to be a good predictor of the ENV responses for most primary-like and chopper units. The current data also reveal a high level of diversity in responses across unit types. TFS cues are mainly conveyed by low-frequency and primary-like units and ENV cues by chopper and onset units. The diversity of responses exhibited by cochlear nucleus neurons provides a neural basis for a dual-coding scheme of FM in the brainstem based on both ENV and TFS cues. Natural sounds, including speech, convey informative temporal modulations in frequency. Understanding how the auditory system represents those frequency modulations (FM) has important implications as robust sound source recognition depends crucially on the reception of low-rate FM cues. Here, we recorded 115 single-unit responses from the ventral cochlear nucleus in response to FM and provide the first physiological evidence of a dual-coding mechanism of FM via synchronization to temporal envelope cues and phase locking to temporal fine structure cues. We also demonstrate a diversity of neural responses with different coding specializations. These results support the dual-coding scheme proposed by psychophysicists to account for FM sensitivity in humans and provide new insights on how this might be implemented in the early stages of the auditory pathway.