Event-related Potentials reveal differential Brain Regions implicated in Discounting in Two Tasks

The way people make decisions about future benefits – termed discounting - has important implications for both financial planning and health behaviour. Several theories assume that, when delaying gratification, the lower weight given to future benefits (the discount rate) declines exponentially. However there is considerable evidence that it declines hyperbolically with the rate of discount being proportionate to the delay distance. There is relatively little evidence as to whether neural areas mediating time- dependent discounting processes differ according to the nature of the task. The present study investigates the potential neurological mechanisms underpinning domain-specific discounting processes. We present high-density event-related potentials (ERPs) data from a task in which participants were asked to make decisions about financial rewards or their health over short and long time-horizons. Participants (n=17) made a button-press response to their preference for an immediate or delayed gain (in the case of finance) or loss (in the case of health), with the discrepancy in the size of benefits/losses varying between alternatives. Waveform components elicited during the task were similar for both domains and included posterior N1, frontal P2 and posterior P3 components. We provide source dipole evidence that differential brain activation does occur across domains with results suggesting the possible involvement of the right cingulate gyrus and left claustrum for the health domain and the left medial and right superior frontal gyri for the finance domain. However, little evidence for differential activation across time horizons is found.Decision Making, Domain-Specific Discounting, Event-Related Potentials

Event-Related Potentials Reveal Differential Brain Regions Implicated in Discounting in Two Tasks

The way people make decisions about future benefits termed discounting - has important implications for both financial planning and health behaviour. Several theories assume that, when delaying gratification, the lower weight given to future benefits (the discount rate) declines exponentially. However there is considerable evidence that it declines hyperbolically with the rate of discount being proportionate to the delay distance. There is relatively little evidence as to whether neural areas mediating timedependent discounting processes differ according to the nature of the task. The present study investigates the potential neurological mechanisms underpinning domain-specific discounting processes. We present high-density event-related potentials (ERPs) data from a task in which participants were asked to make decisions about financial rewards or their health over short and long time-horizons. Participants (n=17) made a button-press response to their preference for an immediate or delayed gain (in the case of finance) or loss (in the case of health), with the discrepancy in the size of benefits/losses varying between alternatives. Waveform components elicited during the task were similar for both domains and included posterior N1, frontal P2 and posterior P3 components. We provide source dipole evidence that differential brain activation does occur across domains with results suggesting the possible involvement of the right cingulate gyrus and left claustrum for the health domain and the left medial and right superior frontal gyri for the finance domain. However, little evidence for differential activation across time horizons is found.

Default Mode Network alterations in alexithymia: An EEG power spectra and connectivity study

Recent neuroimaging studies have shown that alexithymia is characterized by functional alterations in different brain areas [e.g., posterior cingulate cortex (PCC)], during emotional/social tasks. However, only few data are available about alexithymic cortical networking features during resting state (RS). We have investigated the modifications of electroencephalographic (EEG) power spectra and EEG functional connectivity in the default mode network (DMN) in subjects with alexithymia. Eighteen subjects with alexithymia and eighteen subjects without alexithymia matched for age and gender were enrolled. EEG was recorded during 5 min of RS. EEG analyses were conducted by means of the exact Low Resolution Electric Tomography software (eLORETA). Compared to controls, alexithymic subjects showed a decrease of alpha power in the right PCC. In the connectivity analysis, compared to controls, alexithymic subjects showed a decrease of alpha connectivity between: (i) right anterior cingulate cortex and right PCC, (ii) right frontal lobe and right PCC, and (iii) right parietal lobe and right temporal lobe. Finally, mediation models showed that the association between alexithymia and EEG connectivity values was directed and was not mediated by psychopathology severity. Taken together, our results could reflect the neurophysiological substrate of some core features of alexithymia, such as the impairment in emotional awareness

Decision Making and the Brain: Neurologists' View

The article reflects the fact, that concepts like decision making and free will have entered the field of cognitive neuroscience towards the end of 20th century. It gives an overview of brain structures involved in decision making and the concept of free will; and presenting the results of clinical observations and new methods (functional neuroimaging, electrophysiology) it postulates possible mechanisms of these processes. We give a review of the neuroanatomy, specially discussing those parts of the brain important to the present topic, because the process of decision making is dependent on deep subcortical as well as superficial cortical structures. Dopamine has a central role in the in process of reward related behaviour and hedonism. A list of brain structures, related to dopamine action, is also given. The article especially concentrates on the Single Photon Emission Computer Tomography studies in patients with Parkinson's disease (neuroimaging), as well as to the studies concerning the Readiness Potential and Endogeneous Potential P300 (electrophysiology). In the end, we discuss the volition, whose functional anatomy overlaps with the functional anatomy of free will and decision making processes.cognitive neuroscience, brain, decision making, free will, electrophysiology, functional imaging, dopamine

The functional organization of the brain for mental imagery and image rotation: an electroencephalographic investigation

The intent of this dissertation was to reveal (by utilizing a set of cognitive tasks that are visuospatial in nature) how complex mental tasks are performed in the brain. Particular attention was devoted to the functional systems subserving the processes comprising the complex internal generation of mental images and their rotation;Utilizing Electroencephalography (more specifically, alpha power reduction), the functional system subserving the processes of mental rotation and mental image generation was identified. In this functional system, the occipital lobes are bilaterally involved in the initial encoding of visual information into a neural representation. These representations are then shunted to the parietal lobes, with the left parietal lobe specifically involved in generating the three dimensional representation of the stimuli, while actual mental rotation is mediated by left temporal lobe. All of the above subprocesses are completed under the auspices of the right frontal lobe which appears to be involved in mediating comparison and decision subcomponents of the task. In cases where stimuli need to be resampled for further analysis, the right occipital lobe played an important role;The most significant findings of this dissertation are that multiple brain locales are involved in performance of complex visuospatial tasks, and that these locales can be quite remote from one another, with some residing in left hemisphere and some in the right. It is apparent that some of the existing confusion in the literature exploring hemispheric superiority for image generation and mental rotation may be partly attributed to the mistaken expectation that one hemisphere is solely involved in performing a given spatial task. Recent advances in brain imaging technology (like the one employed here) are rapidly changing this manner of thinking