The Prognosis in Insanity

1883 ◽  
Vol 29 (126) ◽  
pp. 188-205
Author(s):  
D. G. Thomson

Mental Exaltation, Mania.—The question of the Prognosis in Mental Exaltation—Mania—in its various forms, is a far more debatable and uncertain matter than in melancholia. The symptoms in melancholia being of a negative character due to a lowering or suspension of brain activity, we do not look for all those diversities, endless varieties and aspects which we may find in mania, be it simple, acute, or chronic. Generally there is an increased vitality, a state of hyperæsthesia, an increase in the activity of the brain, generally of the whole brain, and we must believe that these states will not so easily end in complete resolution as the condition of merely depressed action, or rather no action, which obtains in melancholia—I mean in melancholia generally, and not those states of acute melancholia which are supposed to be closely allied to the state which in other brains and under other subjective circumstances would give rise to mania from a pathological point of view. If this increased activity does not rapidly terminate in resolution, one of two things must occur—either exhaustion or atrophy, resulting in death or dementia, will supervene, or abnormal tissue will invade or replace healthy nerve paths or areas, and chronic aberration of mind ensue.


2021 ◽  
pp. 1-10
Author(s):  
Shahul Mujib Kamal ◽  
Norazryana Mat Dawi ◽  
Hamidreza Namazi

BACKGROUND: Walking like many other actions of a human is controlled by the brain through the nervous system. In fact, if a problem occurs in our brain, we cannot walk correctly. Therefore, the analysis of the coupling of brain activity and walking is very important especially in rehabilitation science. The complexity of movement paths is one of the factors that affect human walking. For instance, if we walk on a path that is more complex, our brain activity increases to adjust our movements. OBJECTIVE: This study for the first time analyzed the coupling of walking paths and brain reaction from the information point of view. METHODS: We analyzed the Shannon entropy for electroencephalography (EEG) signals versus the walking paths in order to relate their information contents. RESULTS: According to the results, walking on a path that contains more information causes more information in EEG signals. A strong correlation (p= 0.9999) was observed between the information contents of EEG signals and walking paths. Our method of analysis can also be used to investigate the relation among other physiological signals of a human and walking paths, which has great benefits in rehabilitation science.



Author(s):  
Soomi Lee ◽  
Susan T Charles ◽  
David M Almeida

Abstract Objectives Participating in a variety of daily activities (i.e., activity diversity) requires people to adjust to a variety of situations and engage in a greater diversity of behaviors. These experiences may, in turn, enhance cognitive functioning. This study examined associations between activity diversity and cognitive functioning across adulthood. Method Activity diversity was defined as the breadth and evenness of participation in seven common daily activity domains (e.g., paid work, time with children, leisure, physical activities, volunteering). Participants from the National Survey of Daily Experiences (NSDE: N = 732, Mage = 56) provided activity data during eight consecutive days at Wave 1 (W1) and Wave 2 (W2) 10 years apart. They also provided cognitive data at W2. Results Greater activity diversity at W2 was associated with higher overall cognitive functioning and higher executive functioning at W2. Individuals who increased activity diversity from W1 to W2 also exhibited higher scores in overall cognitive functioning and executive functioning at W2. Overall cognitive functioning, executive functioning, and episodic memory were better in those who had higher activity diversity at both waves, or increased activity diversity from W1 to W2, compared to those who had lower activity diversity or decreased activity diversity over time. Discussion Activity diversity is important for cognitive health in adulthood. Future work can study the directionality between activity diversity and cognitive functioning and underlying social and neurological mechanisms for these associations.



2011 ◽  
Vol 23 (11) ◽  
pp. 3620-3636 ◽  
Author(s):  
David B. Miele ◽  
Tor D. Wager ◽  
Jason P. Mitchell ◽  
Janet Metcalfe

Judgments of agency refer to people's self-reflective assessments concerning their own control: their assessments of the extent to which they themselves are responsible for an action. These self-reflective metacognitive judgments can be distinguished from action monitoring, which involves the detection of the divergence (or lack of divergence) between observed states and expected states. Presumably, people form judgments of agency by metacognitively reflecting on the output of their action monitoring and then consciously inferring the extent to which they caused the action in question. Although a number of previous imaging studies have been directed at action monitoring, none have assessed judgments of agency as a potentially separate process. The present fMRI study used an agency paradigm that not only allowed us to examine the brain activity associated with action monitoring but that also enabled us to investigate those regions associated with metacognition of agency. Regarding action monitoring, we found that being “out of control” during the task (i.e., detection of a discrepancy between observed and expected states) was associated with increased brain activity in the right TPJ, whereas being “in control” was associated with increased activity in the pre-SMA, rostral cingulate zone, and dorsal striatum (regions linked to self-initiated action). In contrast, when participants made self-reflective metacognitive judgments about the extent of their own control (i.e., judgments of agency) compared with when they made judgments that were not about control (i.e., judgments of performance), increased activity was observed in the anterior PFC, a region associated with self-reflective processing. These results indicate that action monitoring is dissociable from people's conscious self-attributions of control.



2020 ◽  
Author(s):  
Carlos Coronel-Oliveros ◽  
Rodrigo Cofré ◽  
Patricio Orio

AbstractSegregation and integration are two fundamental principles of brain structural and functional organization. Neuroimaging studies have shown that the brain transits between different functionally segregated and integrated states, and neuromodulatory systems have been proposed as key to facilitate these transitions. Although computational models have reproduced the effect of neuromodulation at the whole-brain level, the role of local inhibitory circuits and their cholinergic modulation has not been studied. In this article, we consider a Jansen & Rit whole-brain model in a network interconnected using a human connectome, and study the influence of the cholinergic and noradrenergic neuromodulatory systems on the segregation/integration balance. In our model, a newly introduced local inhibitory feedback enables the integration of whole-brain activity, and its modulation interacts with the other neuromodulatory influences to facilitate the transit between different functional states. Moreover, the new proposed model is able to reproduce an inverted-U relationship between noradrenergic modulation and network integration. Our work proposes a new possible mechanism behind segregation and integration in the brain.



2009 ◽  
Vol 12 (1) ◽  
pp. 32-45 ◽  
Author(s):  
Elena V. Aslanyan ◽  
Valery N. Kiroy

In a series of studies, in which 19 apparently healthy male volunteers participated, on the basis of a comparative analysis of the bioelectric brain activity and work performance, it is shown that two strategies of adaptation to the factors of monotony are possible. One of them is based on the maintenance of a high quality of activity even at the price of a considerable reduction in the functional state of the brain; the second is based on the maintenance of the functional status of the brain even at the expense of the short-term loss of control over realizable performance. The factor conditioning the long term inability to support continual high quality of performance under the conditions of monotony is a high lability in nervous processes. The resistance to the effects of the factors of monotony is connected, on the other hand, with the low lability of nervous processes with a certain predominance of excitatory processes over inhibiting processes. The electrographic correlates of the development of the state of monotony represent an increase in the EEG of an alert person of the slow spectra (theta and alpha), and also beta-2 waves, as well as a reduction in the intrahemispheric coherence of alpha-waves. These results can be used for the development of control systems for the state of the operators who work in conditions of monotony (pilots, the operators of electric trains, the operators of power plants, including atomic power plants, and others), as well as in the occupational selection of individuals for jobs involving work under such conditions.



2021 ◽  
Author(s):  
Jaakko Paasonen ◽  
Petteri Stenroos ◽  
Hanne Laakso ◽  
Tiina Pirttimaki ◽  
Ekaterina Paasonen ◽  
...  

Understanding the link between the brain activity and behavior is a key challenge in modern neuroscience. Behavioral neuroscience, however, lacks tools to record whole-brain activity in complex behavioral settings. Here we demonstrate that a novel Multi-Band SWeep Imaging with Fourier Transformation (MB-SWIFT) functional magnetic resonance imaging (fMRI) approach enables whole-brain studies in spontaneously behaving head-fixed rats. First, we show anatomically relevant functional parcellation. Second, we show sensory, motor, exploration, and stress-related brain activity in relevant networks during corresponding spontaneous behavior. Third, we show odor-induced activation of olfactory system with high correlation between the fMRI and behavioral responses. We conclude that the applied methodology enables novel behavioral study designs in rodents focusing on tasks, cognition, emotions, physical exercise, and social interaction. Importantly, novel zero echo time and large bandwidth approaches, such as MB-SWIFT, can be applied for human behavioral studies, allowing more freedom as body movement is dramatically less restricting factor.



2002 ◽  
Vol 14 (6) ◽  
pp. 303-321 ◽  
Author(s):  
Mark K. Borsody ◽  
Jay M. Weiss

Activity of locus coeruleus (LC) neurons, the major noradrenergic cell-body group in the brain whose axons give rise to approximately 70% of norepinephrine (NE) in the brain, is believed to play an important role in attention/vigilance, cognitive functions and behavioral disorders, particularly depression. Results described here show that in the rat, intraperitoneal (i.p.) injection of lipopolysaccharide (LPS, a bacterial endotoxin) causes long-lasting changes in electrophysiological activity of LC neurons that are mediated by interleukin-1 (IL-1) acting locally in the LC region. First, it was found that IL-1, when microinjected into the LC region or stimulated/expressed in that brain region, increased activity of LC neurons. The only exception to this was that a very low dose of microinjected IL-1 (5 pg) decreased LC activity, which could be blocked by an antagonist to corticotropin-releasing hormone (CRH), thus suggesting that the decrease was due to IL-1 stimulation of CRH release. All of these effects could be blocked by injection and/or infusion of IL-1 receptor antagonist (IL-1RA) specifically into the LC region. Next, intraperitoneal (i.p.) injection of a low dose of LPS(10 µg/kg or 100 ng/kg) was also found to increase LC activity. The excitation of LC produced by 10 µg/kg i.p. LPS increased progressively for at least 1 week, with LC neurons firing at more than twice their normal rate at 1 week after the i.p. LPS injection. Alteration of LC activity lasted for 3 weeks after a single i.p. injection of 10 µg/kg LPS. The effects of i.p. LPS on LC activity at any time after i.p. injection could be blocked by a brief microinfusion of IL-1RA into the LC region, thereby indicating that changes in LC activity seen after the i.p. LPS were caused by IL-1 acting in the LC region. Finally, i.p. injection of peptidoglycan, representing gram-positive bacteria, and polyinsinic-polycytidylic acid [poly(I):(C)], representing viral infection, also caused increases in LC activity, and the effects of peptidoglycan [but not those of poly(I):(C)] were blocked by microinfusion of IL-1RA into LC. These findings suggest that bacterial infections can give rise to prolonged changes in brain activity through cytokine action in brain.



2021 ◽  
Vol 17 (2) ◽  
pp. e1008737
Author(s):  
Carlos Coronel-Oliveros ◽  
Rodrigo Cofré ◽  
Patricio Orio

Segregation and integration are two fundamental principles of brain structural and functional organization. Neuroimaging studies have shown that the brain transits between different functionally segregated and integrated states, and neuromodulatory systems have been proposed as key to facilitate these transitions. Although whole-brain computational models have reproduced this neuromodulatory effect, the role of local inhibitory circuits and their cholinergic modulation has not been studied. In this article, we consider a Jansen & Rit whole-brain model in a network interconnected using a human connectome, and study the influence of the cholinergic and noradrenergic neuromodulatory systems on the segregation/integration balance. In our model, we introduce a local inhibitory feedback as a plausible biophysical mechanism that enables the integration of whole-brain activity, and that interacts with the other neuromodulatory influences to facilitate the transition between different functional segregation/integration regimes in the brain.



2021 ◽  
Vol 15 ◽  
Author(s):  
Hans Albert Braun

If one accepts that decisions are made by the brain and that neuronal mechanisms obey deterministic physical laws, it is hard to deny what some brain researchers postulate, such as “We do not do what we want, but we want what we do” and “We should stop talking about freedom. Our actions are determined by physical laws.” This point of view has been substantially supported by spectacular neurophysiological experiments demonstrating action-related brain activity (readiness potentials, blood oxygen level–dependent signals) occurring up to several seconds before an individual becomes aware of his/her decision to perform the action. This report aims to counter the deterministic argument for the absence of free will by using experimental data, supplemented by computer simulations, to demonstrate that biological systems, specifically brain functions, are built on principle randomness, which is introduced already at the lowest level of neuronal information processing, the opening and closing of ion channels. Switching between open and closed states follows physiological laws but also makes use of randomness, which is apparently introduced by Brownian motion – principally unavoidable under all life-compatible conditions. Ion-channel stochasticity, manifested as noise, function is not smoothed out toward higher functional levels but can even be amplified by appropriate adjustment of the system’s non-linearities. Examples shall be given to illustrate how stochasticity can propagate from ion channels to single neuron action potentials to neuronal network dynamics to the interactions between different brain nuclei up to the control of autonomic functions. It is proposed that this intrinsic stochasticity helps to keep the brain in a flexible state to explore diverse alternatives as a prerequisite of free decision-making.



2009 ◽  
pp. 121-126
Author(s):  
M Ďurfinová ◽  
M Brechtlová ◽  
B Líška ◽  
Ž Barošková

K+-p-nitrophenylphosphatase (K+pNPPase) is the enzyme, which is considered to be involved in K+-dependent hydrolysis of the phosphoenzyme in the reaction cycle of Na+, K+-ATPase. The aim of our present study was to characterize some features of K+pNPPase in homogenates of the rat brain and liver. We determined p-nitrophenylphosphatase (pNPPase) activity in the presence of various ion combinations (Mg2++K+, Mg2+, K+). We found a higher total pNPPase activity in the brain (0.8±0.079 nkat/mg protein) than in the liver (0.08±0.01 nkat/mg protein). Contrary to the liver, the main part of the total brain activity was K+-dependent. The activity of K+pNPPase was significantly higher in cerebral cortex homogenates (0.86±0.073 nkat/mg protein) in comparison to those of the whole brain (0.57±0.075 nkat/mg protein). The specific K+pNPPase activity was two times higher in the isolated pellet fraction (0.911±0.07 nkat/mg protein), rich in synaptosomes, compared to the whole brain homogenate (0.57±0.075 nkat/mg protein). Our results demonstrate the high activity of K+pNPPase in the brain tissue and its distribution mainly into the pellet fraction, what might indicate a possible role of K+pNPPase in specific structures of the brain, e.g. in synaptosomes.



Sign in / Sign up

Export Citation Format

Share Document