In business, a pessimistic mood prevents people from investing. If you're pessimistic , you see a beautiful waterfall and assume you're going to die in it. Here are some examples of the word:. Most people are a little of both, and you can certainly be optimistic — you just learned new words! Or pessimistic — you'll probably just forget them, though. An optimistic person thinks the best possible thing will happen, and hopes for it even if it's not likely. So what did you come up with?

Was it mostly positive stuff like: "My day's going great! My grandmother made me pancakes for breakfast. I sat with my friends at lunch, and I actually enjoyed English class today! My friends wasted the entire lunch period gossiping about a boring TV show, and I had English class today. I hate Thursdays! Researchers have spent a lot of time studying people who think positively. It turns out that an optimistic attitude helps us be happier, more successful, and healthier. Optimism can protect against depression — even for people who are at risk for it.

An optimistic outlook makes people more resistant to stress. Optimism may even help people live longer. The best thing about optimism is you can learn it, even if your outlook tends to be more pessimistic. Optimism and pessimism are mindsets — ways of thinking and seeing things. Optimists see the positive side of things. They expect things to turn out well. They believe they have the skill and ability to make good things happen. You've probably heard people who tend to see the faults in everything called "pessimists.

People aren't always optimistic or always pessimistic, but most people tend to lean toward one of these thinking patterns. The good news is, if you tend to be more pessimistic, you're not destined to always think that way. We can all become more optimistic by adjusting the way we see things.

Optimism goes beyond seeing the bright side of a situation or expecting good things. It's also a way of explaining what has already happened. When something good happens, optimists think about what they did to make the situation turn out so well. They see their abilities as permanent, stable parts of themselves. They think of how this good thing can lead to other good things.

When things don't go as expected, it's the reverse: Optimists don't blame themselves. They see setbacks as temporary. When something goes wrong, optimists link it to a specific situation or event, not their capabilities. The stable-temporary dimension refers to whether the cause of a particular event is one that will remain stable across time or is more transient in nature. A pessimistic explanatory style involves attributing negative events to internal, stable, and global factors e.

In contrast, an optimistic explanatory style involves external, temporary, and specific causal attributions for negative events e. Research has demonstrated that a pessimistic explanatory style is related to depressive symptoms and poorer physical health e. Individuals with an optimistic explanatory style often use problem-focused coping strategies that involve active attempts to cope with a problem by engaging in direct problem solving e.

In many cases, such an approach is highly adaptive. However, the use of problem-focused coping strategies may result in wasted effort when the problem is not subject to change or the individual does not have adequate resources to implement such change.

An optimistic explanatory style works well during childhood, adolescence, and much of adulthood, but it may be mal-adaptive in later life when individuals often face circumstances that are less amenable to change e.

Emotion-focused coping, in which individuals attempt to regulate their emotions, may be more adap-tive than wasting time and energy on problem-solving attempts in such circumstances.

It may be most adaptive for individuals to tailor their explanatory style to the particular event with which they are faced. Defensive pessimism refers to a cognitive strategy of setting low expectations for some upcoming event, thereby preparing for and protecting oneself from potential failure.

Then, after considering all the things that could possibly go wrong, he or she plans carefully to prevent each feared event from occurring.

Strategic optimism refers to a strategy of setting high expectations that are consistent with self-perceptions and past experiences.

This strategy avoids thoughts about possible negative outcomes associated with an upcoming task while preparing for the task. For instance, a person who has to deliver a formal speech would demonstrate strategic optimism by anticipating on the basis of past performance that he or she will do well and beginning to prepare for the speech at an appropriate time.

Although few studies have examined the genetic basis of optimism and pessimism, scholars generally provide heritability estimates of approximately. In a morphometric study, patients with various neurodegenerative diseases underwent a set of neuropsychological tests and the researchers asked them, after the assessment, to rate how well they think they did on the tests compared to other people.

Analysis of the correlation between the patients' estimates of their own cognitive performance and their brain scan images found that reduced gray matter volume in the right ventromedial prefrontal cortex vmPFC was associated with greater overestimation of one's abilities, and that the accuracy of self-appraisal correlated positively with the tissue size in the RH vmPFC [ 71 ].

Similarly, a study on individuals with traumatic brain injuries mostly resulting from automobile accidents found that a more accurate insight into one's post-injury cognitive deficits was associated with the functioning of specific neural networks in the RH [ 72 ].

These studies underscore the RH involvement in mediating a more realistic and less exaggerated evaluation of oneself. It is one of the factors leading to a sense of happiness and a general success in life [ 73 ]. Self-esteem is closely linked with one's basic outlook on life and the motivation to deal with challenges. Those with a high self-esteem feel confident, capable, worthy and tend to be optimistic, whereas people with a low self-esteem are typically more critical of themselves, somewhat insecure, often feel incapable of dealing with life's challenges, and are generally pessimistic [ 74 , 75 ].

Psychological studies show that high self-esteem is associated with the LH. In a dichotic listening experiment, words describing positive or negative traits were presented either to the right-ear i. LH or to the left-ear i. RH and participants' task was to attribute each of these traits either to themselves or to other people.

Faster response times for linking good qualities to themselves and negative traits to others were observed when the words were presented through the right-ear [ 76 ]. Similarly, rightward errors in the line bisection test, which indicate a relative LH hyperfunctioning, were associated with a tendency of participants to describe themselves as active, dominant, mighty, powerful and strong [ 77 ].

EEG studies revealed that a greater physiological activity in the frontal parts of the LH, relative to the RH, is associated with a higher self-esteem [ 78 , 79 ], a general sense of happiness and well-being [ 80 , 81 ], as well as a better resilience and recovery from an abusive childhood [ 82 ]. In contrast, greater physiological activity in the frontal parts of the RH is associated with an increased risk of feeling hopeless about negative events in one's life, and a higher likelihood of falling into depression [ 83 ].

Likewise, neurological reports suggest that LH stroke patients, whose emotional and psychological profile presumably reflect the intact RH, have a relatively lower self-esteem [ 84 ], and their caregivers suffer from greater stress [ 85 ], as compared to RH stroke patients.

These studies demonstrate how a high self-esteem and good appreciation of oneself are associated with the LH, while a low self-esteem and a negative attitude are linked with the RH. Accordingly, the RH involvement in negative-thinking and low self-esteem is reflected also in body image perceptions.

Healthy women viewed size-distorted pictures of themselves and had to decide for each image whether it was fatter or thinner than their real body. The results indicated that when the pictures were presented in the left visual-field i.

In a rare psychiatric disorder, called 'body integrity identity disorder' BIID , able-bodied individuals feel that their body form is inappropriate and desire an amputation of their own limb, which they describe as not belonging to them [ 87 ]. Furthermore, the majority of these individuals desire a removal of their left limb [ 89 , 90 ] which is innervated by the RH. These findings imply that dissatisfaction with one's body shape is associated with neurophysiological processes in the RH.

The RH also mediates a more critical and harsher judgement about other people's faces and bodies. When adults and children judged facial images of boys and girls with strabismus, a squinting right-eye was rated as more disturbing than a squinting left-eye [ 91 ].

Given that the right-eyes in the photographs were within the perceiver's left visual-field and processed initially by his RH, and vice versa for the left-eyes, these findings suggest that the RH is involved, more than the LH, in mediating an unfavourable look at bodily imperfections. Together, these studies link the RH with a relatively less favorable viewpoint. That is, the tendency to see more body imperfections real or imagined and exaggerate their significance is associated primarily with the RH.

When faced with obstacles on the way toward a desired goal, the pessimist will usually give-up quite fast. Volunteers in an experiment squeezed a rubber ball either with their right or left hand.

This physical exercise, which its purpose was hidden from the participants, was aimed to selectively activate the contralateral hemisphere that executed the muscle activations.

Then, participants received a cognitive challenge; to trace some figure drawings without backtracking or removing the pencil from the paper. Two of these puzzles were easily soluble but the other two were insoluble. In another study, the hemispheres were unilaterally stimulated by a passive sensory stimulation - tactile vibrations applied to the contralateral hand - instead of active ball squeezing.

Similar results were obtained; the LH-stimulated group showed greater persistence in trying to solve the insoluble puzzles [ 97 ]. Personal growth and success - achievement of meaningful things and desired states - require courage and readiness to take some risks, i. Optimism leads one to take more reasonable risks, whereas pessimism is associated with a reduced tolerance for risks [ , ].

Apart from extreme conditions where risk-taking can be motivated by hopelessness and a desperate sense of 'there is nothing to lose anymore' [e. Rather, taking a risk reflects the person's optimistic forecast that the outcome will be favorable.

There is evidence in the literature that risk-taking is associated with the LH and risk-avoidance with the RH. Induction of a rightward attentional orientation thereby activating the LH can increase the propensity for risk-taking [ ]. Similarly, LH dominance, as indicated by the line bisection test, is associated with a higher preference for risks [ 32 ].

Risk aversion, on the other hand, is positively correlated with baseline cortical activity in the right prefrontal cortex [ ]. Likewise, brief interruptions of inter-hemispheric balance with tDCS or TMS can affect a person's choice in decisions that involve risk-taking.

Enhancement of the RH activity resulted in less risky decisions in a gambling session [ ], while disruption of the RH activity or enhancement of the LH activity is capable of inducing more risky behaviors [ , ]. When patients with unilateral lesions in the prefrontal cortex played the Iowa Gambling Task a measure for risk-taking , those with the RH-lesion preferred the riskier decks, compared to LH-lesion patients and controls, and this preference correlated with the lesion volume [ , ].

Collectively, these studies suggest that risk-taking is mediated by the LH and that the RH mediates the temperance and suppression of risk-taking tendencies. At the broader context of hemispheric asymmetry in optimism and pessimism, risk-taking and risk-avoidance are behavioral manifestations of these attitudes, respectively. Perhaps, the most striking evidence, for the two hemispheres asymmetric role in mediating optimism and pessimism, comes from the association between the RH physiological activity and depression - a pathological state of pessimism.

Depression is characterized by overly pessimistic thoughts, a negative-thinking style and a tendency to focus and ruminate on what is wrong and magnify it, while ignoring the good things in one's life. Furthermore, the severity of the illness correlates with the relative imbalance of the physiological activity in the two hemispheres [ , ].

Accordingly, recovery from depression is associated with a restoration of the inter-hemispheric balance. Studies of different treatment methods e. In addition, some novel treatments for depression are based on the principle of directly manipulating the brain's physiological activity, in an attempt to restore the inter-hemispheric balance - i.

Three of these methods, EEG neurofeedback, TMS and tDCS have been shown to alleviate depressive symptoms while reinstating a balanced neurophysiological activity [ - ]. Similarly, right-ear CVS which temporarily increases activity in the contarlateral LH thereby minimizing the inter-hemispheric imbalance in depression has been proposed as an alternative or complementary treatment for alleviating depression [ , ].

While the extreme pessimism of depression is associated with a hyperfunctioning RH, mania - elevated mood, euphoria and unjustified optimism - occurs when the LH is hyperactivated. Neurological reports indicate that whilst patients with LH stroke i. Similarly, Parkinson's disease typically starts with asymmetrical motor deficits; the side with the most severe motor symptoms is contralateral to the hemisphere with the worst dopamine denervation. A study found that patients with motor impairments predominantly on the left-hand - indicating a damaged RH and a relatively less-damaged LH - have higher frequencies of hypomania [ ].

Likewise, injection of a sedative drug sodium amobarbital to the left carotid artery - thereby anesthetizing the LH - resulted in crying, pessimistic statements and worries about the future, whereas sedation of the RH produced smiling, laughing, elated mood and euphoric reactions [ - ]. In the same line, left-ear CVS had been used as an effective technique to reduce manic symptoms; presumably, activating the contralateral RH that mediates pessimism re-balances the inter-hemispheric dynamics [ , ].

Suicide attempts reflect the ultimate pessimistic state and extreme hopelessness. An EEG comparison between healthy girls and those who tried to commit suicide but failed, found a greater physiological activity in the RH among the suicide-attempters group [ ].

Further analysis revealed that this greater RH activation was more notable among the individuals who really intended to die i. Similarly, suicidal patients were reported to have a larger right amygdala than non-suicidal patients [ ]. In addition, a postmortem histological analysis revealed a greater density of von Economo neurons in the right anterior cingulate cortex of suicide victims, compared to individuals who died from other causes [ ].

Together, these studies further demonstrate that pessimistic mood is strongly interlinked with the RH at the physiological level i. The aforementioned studies demonstrate clearly that optimistic and pessimistic thoughts, attitudes, moods and behaviors are lateralized in the brain.

Optimism is associated with physiological activity in the LH, whilst pessimism is linked with the RH. This leads to the question: what are the underlying biological mechanisms that can explain this difference between the two hemispheres?

More specifically, is there something in the RH neurophysiology and functions that make it more suitable to mediate and sustain pessimistic thinking patterns? Similarly, what is it in the LH physiology that enables it to mediate a less vulnerable and more resilient optimistic attitude? Various studies suggest that the RH mediates a relatively more watchful and fearful mode, than the LH; a mental state which seems to be the major factor in the link between the RH and pessimistic thought patterns.

The peripheral autonomic nervous system regulates visceral functions via two branches; the sympathetic and parasympathetic nervous systems SNS and PSNS, respectively. The SNS prepares the body to respond to a potential threat or danger by increasing heartbeats in order to accelerate blood supply to the motor organs.

The SNS also increases the sweating rate to keep the body temperature cool within the optimal range, it tightens the blood vessels of the gastro-intestinal tract so digestion is slowed and energy is saved, and it dilates the pupils to allow more light to come in and increase far vision. When the threat situation is over and the potential 'fight or flight' response is no longer required, the PSNS functions as a dampener of the SNS effects, thereby restoring physiological regularity and calmness.

For instance, electrical stimulation of the left insular cortex or vibrotactile stimulation applied to the right-hand i. LH slows heartbeats i. Similarly, left insular stroke often shifts cardiovascular functioning toward SNS hyperactivation, presumably due to the loss of the PSNS balancing effects [ , ].

Likewise, pharmacologically induced anesthesia of regions within the LH thereby letting the RH to take control resulted in accelerated heartbeats, while sedation of the RH slowed heartbeats [ , , ].

This principle - that the RH is biologically designed to handle potential threats, more than the LH - is manifested also in the central nervous system. Sub-threshold or masked frightening stimuli are better detected and trigger a greater response in skin conductivity when they are presented in the LVF initially processed by the RH , compared to identical presentations in the RVF [ - ].

Similarly, an increased neural activity in the amygdala, pulvinar and superior colliculus was found when participant viewed fearful facial expressions, compared to neutral expressions, selectively for LVF, but not for RVF, presentations [ , ].

In addition, the startle reflex - the behavioral response of humans and many animals to a sudden fearful stimulus - can be potentiated during perception of negative emotional stimuli and attenuated during perception of positive emotional stimuli [ ]. Experiments showed that the differences in the reflex magnitude between pleasant and unpleasant stimuli were consistently large and reliable for reflexes elicited by left-ear probes i.

RH processing but weak and inconsistent for reflexes elicited by right-ear probes [ ], suggesting that startle modulation is mediated primarily by neural structures within the RH.

Studies on the amygdala - the neural system with the most robust activity during fear - found that the right amygdala reaction to fear conditioned stimuli is faster and longer in duration than the left amygdala [ ].

Likewise, lesions in the right amygdala result in a significantly lower emotional response to fearful images, compared to left amygdala lesions [ , ]. The RH greater involvement in mediating fearful experiences is reflected also in its significant role in regulating the stress hormone cortisol. Higher levels of cortisol induced by stress and anxiety correlated with a greater RH activation [ - ].

There is evidence that post-traumatic stress disorder PTSD - where the original mental trauma is re-experienced through flashbacks and nightmares that re-activate the fear and stress responses - is coupled with an increase in RH activation [ - ]. Similarly, panic disorder and social phobia are associated with a RH hyperactivity [ - ].

This division of labor between the hemispheres is also reflected in the RH relatively greater involvement in automatic orientation of spatial attention [ - ], and in the RH advantage in detecting a change in the environment [ - ]. These superior attentional functions of the RH sustain and complement its role of mediating the SNS processes by maintaining higher alertness and a vigilant mode. The LH, on the contrary, is relatively more involved in routine, well-rehearsed and repetitive responses [ 15 , 16 , ].

This fundamental difference in the physiological and psychological functions of the two hemispheres, in which the LH primary role is to maintain homeostasis and relaxation by keeping physiological activity within normal levels, whereas the RH functions as the 'alarm system' that identifies potential threats and prepares the body to deal with dangerous situations via the SNS , explains very well why pessimistic tendencies are associated with the RH.

Firstly, the RH major role in the detection of potential threats and possible conflicts effectively means that the RH is biologically geared to focus attention on what might go wrong, rather than on what is good. Secondly, pessimism in regard to the unknown that lies ahead is essentially looking at the world through lenses that are stained with fear, anxiety and stress.

Therefore, a pessimistic thinking style that anticipates negative outcomes in the future is naturally associated with the RH physiological activity, since pessimism and worry about the uncertain future contain significant elements of fear, anxiety and stress - emotions that are mediated primarily by neural circuits within the RH. The LH, on the contrary, is biologically designed to keep the body's physiology within normalcy via the PSNS and promote relaxation and balance - mental states that enable positive thinking patterns and optimistic thoughts to thrive and flourish.

A somewhat related functional distinction between the two hemispheres, that can explain their different involvement in processing optimistic and pessimistic attitudes, is Jeffrey Gray's concept of behavioral activation and inhibition systems.

Based on a variety of experimental observations and the principles of behavioral learning theories, Gray [ ] proposed that our interaction with the environment is controlled by two neural systems; the behavioral activation system BAS and the behavioral inhibition system BIS.

The BAS regulates appetitive, positive-incentive motivation, and is manifested in approach behaviors toward potentially rewarding stimuli. Initiation of a verbal response activates regions within the LH, whereas withholding speech engages RH regions [ ]. The LH is involved in approach-related emotions, while the RH is associated with withdrawal-related emotions [ 19 , ]. Cognitive processes show the same hemispheric asymmetry. For instance, a commitment to do a specific act is associated with an increased left frontal activation [ ], presumably by stimulating an 'action mode'.

Likewise, an increased physiological activation in the LH was detected when participants were presented publically with a bogus negative assessment of their personality test, thereby prompting them into an 'active mode' for defending their good reputation [ ]. Similarly, making or avoiding a decision is associated with left and right frontal activations, respectively [ , ].

This functional organization of the two cerebral hemispheres means that the right and left hemispheres subserve different modes of dealing with the environment.

The RH, on the other hand, mediates a cautious mode which balances the drive for actions, and promotes a relatively passive state-of-mind. A major distinctive characteristic between optimistic and pessimistic people is their coping strategies. Optimism is associated with taking an active approach for both maximizing one's well-being and minimizing stressors.

Pessimism, on the contrary, is associated with using mostly escape and avoidance strategies when dealing with distress, as well as with hesitations and a passive attitude when faced with an opportunity. Furthermore, having confidence about eventual success prompts the optimist to continue trying even when the going gets tough, while doubts about the future discourage the pessimist from persisting [ 3 , ]. The link between passivity and pessimism is well exemplified in depression.

A prominent symptom of major depression is psychomotor retardation - an overall slowness and reduction of physical movements [ 59 ]. In severe depression, the process is intensified and the patient may have difficulties in doing mundane and simple motor activities such as taking a shower, dressing, self-grooming, or even getting out of bed. Mental activity and verbal speech are also slowed in depression [ , ]. Accordingly, a unique treatment program for depression - the behavioural activation therapy - attempts to help patients reengage in their lives through focused activation strategies; creating daily schedules of activity, seeking pleasurable experiences and sources of positive reinforcements, as well as breaking the patterns of avoidance, withdrawal and inactivity [ - ].

Similarly, a regular habit of exercise and physical activity can prevent and alleviate depression [ - ]. Similarly, a comparison of athletes and non-athletes in the line bisection test, found that while the latter group tended to deviate leftward from the veridical center, indicating a RH dominance, the athletes deviated rightward [ ], suggesting a link between high levels of physical activity and a LH dominance. Thus, from an inter-hemispheric dynamics perspective, the positive mood that comes with exercise and physical activity is achieved, at least partly, through the increased neural activation in the LH [ , ].

The relationship between activity and optimism is bi-directional. Optimistic thoughts lead to active coping strategies and the rewarding results weave a sense of self-efficacy and mastery over one's environment internal locus-of-control , which further reinforces the proactive attitude.

In contrast, pessimism facilitates a passive attitude which hinders and minimizes positive feedback, thereby further exacerbating a 'learned helplessness' thinking pattern and depressed mood [ - ]. Thus, the LH association with optimism seems to be related also to its mediation of an active approach mode, which enables the positive sense of accomplishment following successful experiences to further promote and reinforce an 'I can do it' attitude and optimism. The RH association with pessimism, on the contrary, is facilitated by its mediation of a relatively passive mode, escape and avoidance coping style, which minimizes and prevents potential positive experiences and their reinforcing effects on one's attitude.

Another account for the lateralization of optimism and pessimism is related to the notion that perceptual and cognitive processes are fundamentally intertwined with actions. According to ecological perception theorists James and Eleanor Gibson, perception is action oriented and essentially it is an adaptive process, sensitive to the feedback an organism receives from its particular environment and its affordances. That is, perception is a reciprocal interaction between a person's potential and actual motor actions and locomotion in the environment and the actionable properties and opportunities that the environment provides for the person.

Therefore, learning occurs mainly through acting in the environment [ - ]. Furthermore, cognitive development theorists Jean Piaget and Lev Vygotsky assert that almost all higher mental functions originally arise from actions, and that, from an evolutionary perspective, the main function of cognition is to guide actions and to contribute to situation-appropriate behaviors [ - ].

Thus, the process of concept formation is essentially a regulatory process of adaptation to the environment. Schemas - the organized patterns of reasoning, emotions and behaviors - begin to form in early infancy at the initial sensory-motor pre-linguistic stage through primitive symbols. Every encounter with something unfamiliar a new object, environment or situation is perceived and understood by reference to previous knowledge. When the new information fits into one's pre-existing schema it is integrated and assimilated into the schema, and when it cannot fit in, the schema is altered to accommodate the new information [ , ].

Typical infant behaviors exemplify this. An infant comes into the world with an inborn reflex of sucking. As this action satisfies the baby's basic needs it is further reinforced. As it grows a bit, the infant starts to suck everything within its reach. By realizing that some objects do not satisfy when sucked, the infant learns to distinguish between eatable and non-eatable objects.

From a cognitive perspective, the infant is engaged in trying to assimilate its new experiences to its existing knowledge that sucking leads to satisfaction and through the interaction with objects that do not confirm that expectation the schema is modified. Cognitive development and intelligence, in children and adults, are therefore a progressive reorganization of knowledge into larger, more elaborated and sophisticated frameworks, a process that results from biological maturation and environmental experiences [ , ].

Crucially, however, schemas are not abstract concepts detached from the nervous system; rather they are based on concrete sensory and motor experiences [ , - ].

Indeed, recent research demonstrates that perceptual, cognitive and emotional processes are inherently embodied. That is, mental processes are grounded in bodily states - i. The following experiments illustrate this point vividly. Participants in a study were asked to hold a pen in their mouth, and simultaneously read several cartoons and rate their funniness. Two groups were compared; one group was asked to hold the pen only with their teeth but not with their lips, a condition that caused them to open their lips widely thereby unconsciously activating the smiling muscles which draw the angle of the mouth upward and backward, whereas the other group was asked to hold the pen only with their lips, a condition that caused them to hold their lips closed thereby inhibiting the production of a smiling facial expression pictures related to this experiment can be found in [ ].

It was found that the former group rated the cartoons as funnier than the latter group [ , ]. Presumably, the activation of the facial muscles associated with smiling evoked the mental representation and some degree of the mood associated with that physiomuscular state and influenced participants' judgments of the humor in the cartoons. Similarly, in another study, participants either pulled a lever toward themselves or pushed it away from themselves while simultaneously watching neutral stimuli and rating them.

The researchers found that the pulling and pushing which imitate arm flexion and extension movements associated in everyday life with liking and disliking something, affected participants' preferences of the neutral stimuli, respectively. That is, in the pulling condition the participants reported higher preferences for the neutral stimuli than in the pushing condition [ , ]. Likewise, experiments in psychology have shown that manipulating participants into experiences of physical warmth, e.

On the other hand, experiences of social exclusion and loneliness, i. This effect presumably occurs because our mind often relies on scaffolding processes whereby newer concepts are built on and make use of older structures; in this case, mental experiences are conceptualized by analogy and linkage to physiological experiences [ , , - ].

Accordingly, early childhood experiences of being cradled and cuddled in the bosom of a loving caregiver form the semantic association between warm sensation and affection more evidence of this semantic link between physical and psychological warmth can be found in the works of John Bowlby [ ] and Mary Ainsworth [ ] with human infants, and in the works of Harry Harlow [ ] with monkey infants. Building on the aforementioned ideas that a mental processes involve operations of schemas - structured networks of symbols, knowledge and feelings linked by conceptual metaphors - and b that schemas are intrinsically shaped by the sensory feedback received through motor and muscular activation, it seems plausible that the laterality in handedness may also have its contribution to the lateralization of optimism and pessimism.

Anatomically, the right-hand is controlled by the LH, and the right-hand dexterity is subserved by a superior neural connectivity in LH motor regions, compared to the homotopic RH areas [ ]. Perhaps, the dexterity associated with the LH and the relative clumsiness associated with the RH, breed a sense of potency and a sense of incompetence, respectively. The early sensory-motor experiences of a child interacting with its environment provide both, positive feedback through the dexterous, smooth and fluent motor actions of the right limbs, as well as negative feedback from the left limbs clumsiness and ineptness.

These primitive sensorimotor experiences of concrete strength and weakness, which are encoded into the LH and RH respectively, constitute the kernel of the child schemas about its abilities and limitations in dealing with environmental challenges. That is, even in the pre-linguistic stage and before the child has a sufficient cognitive capability and conceptual frameworks to comprehend the full meaning of skillfulness and ineptitude, these feelings exist in an intuitive and crude form of a tacit knowledge i.

During development, these schemas evolve further so that experiences of success and failure, confidence and insecurity, as well as more elaborated concepts such as self-esteem i. Schematic presentation of the neural basis of optimism and pessimism. The primitive right and left sensorimotor experiences of concrete strength and weakness, which are encoded into the LH and RH respectively, are the basis of optimism A and pessimism B.

Indeed, studies show a positive correlation between the sense of power - i. Similarly, confidence is robustly associated with hope, optimism and resilience [ , ]. In addition, a sense of power increases active and approach behaviors, while it reduces inhibition and withdrawal tendencies [ , , ] - behavioral patterns that are associated with optimism and pessimism, respectively, as outlined in the previous section.

These cognitive schemas about one's abilities and limitations are ingrained in the activation patterns of their respective neural networks, and as the aforementioned studies suggest they are relatively lateralized in the two cerebral hemispheres. The optimistic schema is scaffolded and assimilated into neural structures and systems within the LH, while the pessimistic schema is primarily associated with, and integrated into, neural circuits and networks in the RH.

Concentration on the shortcomings of a person's environment and conditions, or when the focus on the glass half empty is directed inward in the form of the thought that 'I am not good enough' etc.

However, when taken extremely, it can lead to perfectionism - i. Constant assessments of oneself or comparisons with unattainable high standards are doomed to find flaws and failures.

This vicious cycle further exacerbate negative thinking patterns and may lead to a sense of hopelessness, self-blame and eventually depression. Indeed, studies showed that unhappiness, low self-esteem, pessimism and depression are all linked to the chase after perfectness [ - ].

Accordingly, therapeutic methods for overcoming pessimism and unhappiness concentrate on setting realistically achievable goals for oneself, cultivating a non-judgmental attitude and practicing unconditional self-acceptance - applying compassion, generosity and love to oneself [ , ]. From a neurobiological perspective, it is not a mere coincidence that the RH: a receives a relatively poorer motor feedback and an overall sense of clumsiness and awkwardness, b mediates negative thought patterns i.

Negative thinking, a focus on what's not good, a poor self-image and the strive for perfection are all parts of the same pessimistic schema that is mediated by associated neural networks of the same cerebral hemisphere that registers the sensorimotor feedback and evaluates its meaning i. The early childhood realization of one's relative motor ineptness and physical weakness of the left limbs is the conceptual skeleton on which all subsequent thematically related experiences i.

Since the body-mind relationship is bi-directional - mental states affect body states and body states affect mental states e. LH brain lesions or laboratory induced manipulations of the inter-hemispheric dynamics which provide the RH with a temporary advantage activate the pessimistic schema with its ensuing set of behaviors.

The opposite applies to the LH and the optimistic schema. Optimism and pessimism are both necessary for our survival and wellness. As in many areas of life, the 'golden mean' - the middle between the two extremes of excess and deficiency - is the desirable optimum.

This classic notion is widely accepted in both Western and Eastern cultures which were traditionally influenced by the ideas of Aristotle and Confucius. These philosophers discussed the concepts of symmetry, proportion, harmony, balance and stability, and emphasized the benefits of applying these principles in personal life and social relationships.

Nonetheless, the empirical literature suggests that, in regard to one's general attitude, being in the middle of the optimism-pessimism continuum i. A moderate dose of optimism, although it distorts one's perception of reality to some extent, can be advantageous. Studies that investigated the correlation between optimism and health suggest that optimists generally have better physical health [ ], less cardiovascular diseases [ ] and improved immunological functioning [ ].

Furthermore, optimists and their romantic partners indicated greater satisfaction in their relationships [ ]. A review of the literature on the neurophysiology associated with these two fundamental approaches to life suggests that optimism and pessimism are differentially associated with the two cerebral hemispheres. Attentiveness to the positive aspects of a given situation, a high self-esteem and a belief that the future will be bright are all mediated by the LH. The RH, in contrast, is generally involved in mediating a focus on the negative side, a low self-esteem and a gloomy view about the future.

The biological sources of this hemispheric asymmetry in thinking styles and attitudes are severalfold. The RH is relatively more involved in mediating fear and stress, and it serves as the brain's 'alarm system'. Physiologically, the RH is primed to detect perils and prepare the body for dealing with threats by activating the SNS. This special sensitivity of the RH is necessary for survival, yet it has a negative side; it entails focusing attention on what can potentially go wrong.

Furthermore, a preoccupation with menace is accompanied with fear, anxiety and stress - emotions which further taint and bias one's perception to see the world through negative lenses.

In addition, the RH mediation of a fearful mode sustains a relative passivity - inhibition, escape and avoidance strategies - when dealing with obstacles along the way. These primal biological functions of the RH shape its mode of perceiving the world, and therefore the RH 'sees' more potential troubles than potential opportunities.

This biased perceptual mode gives rise to a general tense feeling of uncertainty and insecurity which breed pessimistic thoughts and attitudes. Consequently, negative views as well as experiences that may strengthen a pessimistic outlook on life are mediated by, and become assimilated into, neural networks in the RH which support and facilitate fear, stress, negative thinking patterns and their ensuing sets of actions.

The LH, on the contrary, is biologically designed to keep the body in physiological equilibrium via the PSNS - a relaxed state that enables optimistic thoughts to thrive and flourish.

In addition, the LH has a more active role in dealing with the environment. This fosters and encourages a proactive mindset of taking the initiative in dealing with life's challenges - a basic component of optimism - and the rewarding results further reinforce an optimistic attitude.

Furthermore, the LH receives, from the early formative years of infancy, a relatively more positive sensory-motor feedback, due to its dexterity and smoothness of actions, compared to the RH.

This motor fluency breeds a sense of confidence and high self-esteem - a feeling that one has a fair degree of control in life and capability to overcome potential obstacles on the way. Accordingly, optimistic thinking patterns and positive experiences that reinforce them are primarily connected with, and integrated into, neural systems within the LH.

However, Mojon-Azzi et al. Therefore, the findings of Mojon-Azzi et al. Therefore, all these neural networks, which are spread throughout each hemisphere, are integral parts of these schemas.

Therefore, most of our knowledge on issues of functional laterality, including the current topic of optimism and pessimism, is relevant mainly to right-handed people. As for the left-handers, theoretically their optimism and pessimism schemas should be lateralized in reverse, i. However, the research on left-handers is inconclusive on this issue. Some studies show that left-handers have a symmetrically reversed functional lateralization. For instance, right-handers perceive positive facial expressions better when they are presented in the RVF i.

LH and negative faces better when they appear in the LVF i. RH , while the reverse is true for some left-handers [ , ]. Likewise, right-handers reported more positive and less negative affect for music played to their right-ear i.

LH , while the same affective experience was obtained for music played to the left-ear i. RH of left-handers [ ]. Similarly, approach motivation tendencies are associated with LH activation in right-handers and with RH activation in left-handers [ , ]. However, some studies on left-handers' emotional lateralization show that it is not a symmetric reverse of right-handers [e. In addition, some inborn left-handers were 'converted' and forced, since childhood, to use their right non-dominant hand for writing and other tasks; an intervention which may have shaped their neural development i.

Furthermore, even non-converted left-handers may not necessarily have a perfect symmetrical reverse of functional laterality for optimism and pessimism, since our world is significantly biased in favor of right-handers.

For instance, most manual tools, equipments, machines and environments are ergonomically designed for the use of right-handers. Besides, although motor dominance and its sensory-motor feedback are hemispherically reversed in left-handers, there is no evidence for a reversal of the association between the SNS and PSNS with RH and LH processes, respectively, in left-handers, though the magnitude of these links, may not be similar in right- and left-handers [e.

Therefore, even though the RH of left-handers receives a motor feedback of relative strengths, this hemisphere is still involved in SNS processes which bias perception and cognition toward a pessimistic mode. National Center for Biotechnology Information , U. Journal List Exp Neurobiol v. Exp Neurobiol. Published online Sep David Hecht. Find articles by David Hecht. Author information Article notes Copyright and License information Disclaimer. Corresponding author. To whom correspondence should be addressed.

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