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In analogy to the appreciation of humor, that of tickling is based upon the re- interpretation of an anticipated emotional situation. Hence, the anticipation of tickling contributes to the final outburst of ticklish laughter. To localize the neuronal substrates of this process, fMRI was conducted on 31 healthy volunteers. The state of anticipation was simulated by generating an uncertainty respecting the onset of manual foot tickling. Anticipation was characterized by an augmented fMRI- signal in the anterior insula, the hypothalamus, the nucleus accumbens and the ventral tegmental area, as well as by an attenuated one in the internal globus pallidus. Furthermore, anticipatory activity in the anterior insula correlated positively with the degree of laughter that was produced during tickling. These findings are consistent with an encoding of the expected emotional consequences of tickling and suggest that early regulatory mechanisms influence, automatically, the laughter circuitry at the level of affective and sensory processing. Tickling activated not only those regions of the brain that were involved during anticipation, but also the posterior insula, the anterior cingulate cortex and the periaqueductal gray matter. Sequential or combined anticipatory and tickling-related neuronal activities may adjust emotional- and sensorimotor pathways in preparation for the impending laughter response.

The burst of laughter that is evoked by tickling is a primitive form of vocalization. It evolves during an early phase of postnatal life and appears to be independent of higher cortical circuits. Clinicopathological observations have led to suspicions that the hypothalamus is directly involved in the production of laughter. In this functional magnetic resonance imaging investigation, healthy participants were 1) tickled on the sole of the right foot with permission to laugh, 2) tickled but asked to stifle laughter, and 3) requested to laugh voluntarily. Tickling that was accompanied by involuntary laughter activated regions in the lateral hypothalamus, parietal operculum, amygdala, and right cerebellum to a consistently greater degree than did the 2 other conditions. Activation of the periaqueductal gray matter was observed during voluntary and involuntary laughter but not when laughter was inhibited. The present findings indicate that hypothalamic activity plays a crucial role in evoking ticklish laughter in healthy individuals. The hypothalamus promotes innate behavioral reactions to stimuli and sends projections to the periaqueductal gray matter, which is itself an important integrative center for the control of vocalization. A comparison of our findings with published data relating to humorous laughter revealed the involvement of a common set of subcortical centers

Early acquisition of a second language influences the development of language abilities and cognitive functions. In the present study, we used functional Magnetic Resonance Imaging (fMRI) to investigate the impact of early bilingualism on the organization of the cortical language network during sentence production. Two groups of adult multilinguals, proficient in three languages, were tested on a narrative task; early multilinguals acquired the second language before the age of three years, late multilinguals after the age of nine. All participants learned a third language after nine years of age. Comparison of the two groups revealed substantial differences in language-related brain activity for early as well as late acquired languages. Most importantly, early multilinguals preferentially activated a fronto-striatal network in the left hemisphere, whereas the left posterior superior temporal gyrus (pSTG) was activated to a lesser degree than in late multilinguals. The same brain regions were highlighted in previous studies when a non-target language had to be controlled. Hence the engagement of language control in adult early multilinguals appears to be influenced by the specific learning and acquisition conditions during early childhood. Remarkably, our results reveal that the functional control of early and subsequently later acquired languages is similarly affected, suggesting that language experience has a pervasive influence into adulthood. As such, our findings extend the current understanding of control functions in multilinguals.

The burst of laughter that is evoked by tickling is a primitive form of vocalization. It evolves during an early phase of postnatal life and appears to be independent of higher cortical circuits. Clinicopathological observations have led to suspicions that the hypothalamus is directly involved in the production of laughter. In this functional magnetic resonance imaging investigation, healthy participants were 1) tickled on the sole of the right foot with permission to laugh, 2) tickled but asked to stifle laughter, and 3) requested to laugh voluntarily. Tickling that was accompanied by involuntary laughter activated regions in the lateral hypothalamus, parietal operculum, amygdala, and right cerebellum to a consistently greater degree than did the 2 other conditions. Activation of the periaqueductal gray matter was observed during voluntary and involuntary laughter but not when laughter was inhibited. The present findings indicate that hypothalamic activity plays a crucial role in evoking ticklish laughter in healthy individuals. The hypothalamus promotes innate behavioral reactions to stimuli and sends projections to the periaqueductal gray matter, which is itself an important integrative center for the control of vocalization. A comparison of our findings with published data relating to humorous laughter revealed the involvement of a common set of subcortical centers.

Auf dem Gebiet der Spracherwerbsforschung gilt es als erwiesen, dass frühe Spracherfahrung die Sprachentwicklung nachhaltig beeinflusst. Der frühe Erwerb einer oder zweier Sprachen müsste sich deshalb unterschiedlich auf die Ausbildung späterer Sprachkompetenzen auswirken. Einige psycholinguistische Untersuchungen konnten dies betätigen. Bis heute wurde jedoch der Einfluss früher Zweisprachigkeit auf die Ausbildung des kortikalen Sprachennetzwerkes wenig erforscht. Diesen Aspekt der Sprachentwicklung untersucht die vorliegende Arbeit mittels funktioneller Magnetresonanztomographie (fMRI). Dazu wurden zwei Gruppen von Mehrsprachigen gebildet: die erste von „frühen Mehrsprachigen“, die eine Zweitsprache (L2) im Kleinkindalter (bis drei Jahren); die zweite von „späten Mehrsprachigen“, die eine Zweitsprache (L2) als Heranwachsende oder später (ab neun Jahren) gelernt haben. Im Gegensatz zu früheren Arbeiten mit bildgebenden Verfahren beherrschten die in dieser Studie erfassten frühen und späten Mehrsprachigen eine weitere, als Heranwachsende oder später erworbene Drittsprache (L3). Die neuronale Hirnaktivität in den drei Sprachen (L1, L2 und L3) früher und später Mehrsprachiger wurde durch eine Sprachproduktionsaufgabe erfasst, somit auch für L3, wodurch der mögliche Einfluss früher Mehrsprachigkeit auf diese Drittsprache zum ersten Mal beurteilt werden konnte. Die sprachliche Aufgabe bestand darin, dass die Probanden in der jeweils getesteten Sprache über die Ereignisse des vergangenen Tages berichten mussten. Um den Einfluss nicht sprachspezifischer Einflüsse wie variable Aufmerksamkeit oder unterschiedlichen Bezug zum gerade Erlebten auf die gemessene Aktivierung zu verringern, wurde die Messung zweimal, und zwar an unterschiedlichen Tagen, durchgeführt. Die Durchschnittsaktivierungen von L1, L2 und L3 wurden für die Gruppen von frühen und späten Mehrsprachigen statistisch berechnet, wobei beide Messungen in die Auswertung einbezogen wurden. Der Vergleich der Hirnakt, Research on language acquisition has shown that language development depends on language experience during early childhood. Early acquisition of one as opposed to two languages should therefore influence the development of language capabilities. Various psycholinguistic studies have provided support for this idea. The impact of early second language acquisition on the establishment of the cortical network, however, remains elusive. In the present study we used functional magnetic resonance imaging (fMRI) to investigate this aspect. Language related brain activity was assessed in two groups of multilinguals with different ages of second language acquisition: “early multilinguals” had acquired a second language (L2) in early childhood (before the age of three years); “late multilinguals” learned a second language (L2) in early adolescence or later (after the age of nine years). Of particular interest was the previously unexplained question of whether the brain representation of languages learned as adolescents or adults is influenced by early second language acquisition. With this perspective in mind, all early and late multilinguals included in the study had also learned a third language (L3) after the age of nine years, so that not only early, but also late learned languages could be compared between both groups. All multilinguals were tested in their three languages (L1, L2 and L3) by fMRI. The brain activity was measured during a language production task in which the subjects had to report the happenings of the previous day. To reduce influences not specifically related to language processes such as variable attention or valuation of the described experiences, the subjects were tested twice, on different days. The average brain activity during processing of L1, of L2 and of L3 has been statistically assessed for the groups of early and late multilinguals separately, including both tested runs. The comparison of the early acquired languages between both groups reve

Auf dem Gebiet der Spracherwerbsforschung gilt es als erwiesen, dass frühe Spracherfahrung die Sprachentwicklung nachhaltig beeinflusst. Der frühe Erwerb einer oder zweier Sprachen müsste sich deshalb unterschiedlich auf die Ausbildung späterer Sprachkompetenzen auswirken. Einige psycholinguistische Untersuchungen konnten dies betätigen. Bis heute wurde jedoch der Einfluss früher Zweisprachigkeit auf die Ausbildung des kortikalen Sprachennetzwerkes wenig erforscht. Diesen Aspekt der Sprachentwicklung untersucht die vorliegende Arbeit mittels funktioneller Magnetresonanztomographie (fMRI). Dazu wurden zwei Gruppen von Mehrsprachigen gebildet: die erste von „frühen Mehrsprachigen“, die eine Zweitsprache (L2) im Kleinkindalter (bis drei Jahren); die zweite von „späten Mehrsprachigen“, die eine Zweitsprache (L2) als Heranwachsende oder später (ab neun Jahren) gelernt haben. Im Gegensatz zu früheren Arbeiten mit bildgebenden Verfahren beherrschten die in dieser Studie erfassten frühen und späten Mehrsprachigen eine weitere, als Heranwachsende oder später erworbene Drittsprache (L3). Die neuronale Hirnaktivität in den drei Sprachen (L1, L2 und L3) früher und später Mehrsprachiger wurde durch eine Sprachproduktionsaufgabe erfasst, somit auch für L3, wodurch der mögliche Einfluss früher Mehrsprachigkeit auf diese Drittsprache zum ersten Mal beurteilt werden konnte. Die sprachliche Aufgabe bestand darin, dass die Probanden in der jeweils getesteten Sprache über die Ereignisse des vergangenen Tages berichten mussten. Um den Einfluss nicht sprachspezifischer Einflüsse wie variable Aufmerksamkeit oder unterschiedlichen Bezug zum gerade Erlebten auf die gemessene Aktivierung zu verringern, wurde die Messung zweimal, und zwar an unterschiedlichen Tagen, durchgeführt. Die Durchschnittsaktivierungen von L1, L2 und L3 wurden für die Gruppen von frühen und späten Mehrsprachigen statistisch berechnet, wobei beide Messungen in die Auswertung einbezogen wurden. Der Vergleich der Hirnakt, Research on language acquisition has shown that language development depends on language experience during early childhood. Early acquisition of one as opposed to two languages should therefore influence the development of language capabilities. Various psycholinguistic studies have provided support for this idea. The impact of early second language acquisition on the establishment of the cortical network, however, remains elusive. In the present study we used functional magnetic resonance imaging (fMRI) to investigate this aspect. Language related brain activity was assessed in two groups of multilinguals with different ages of second language acquisition: “early multilinguals” had acquired a second language (L2) in early childhood (before the age of three years); “late multilinguals” learned a second language (L2) in early adolescence or later (after the age of nine years). Of particular interest was the previously unexplained question of whether the brain representation of languages learned as adolescents or adults is influenced by early second language acquisition. With this perspective in mind, all early and late multilinguals included in the study had also learned a third language (L3) after the age of nine years, so that not only early, but also late learned languages could be compared between both groups. All multilinguals were tested in their three languages (L1, L2 and L3) by fMRI. The brain activity was measured during a language production task in which the subjects had to report the happenings of the previous day. To reduce influences not specifically related to language processes such as variable attention or valuation of the described experiences, the subjects were tested twice, on different days. The average brain activity during processing of L1, of L2 and of L3 has been statistically assessed for the groups of early and late multilinguals separately, including both tested runs. The comparison of the early acquired languages between both groups reve

The burst of laughter that is evoked by tickling is a primitive form of vocalization. It evolves during an early phase of postnatal life and appears to be independent of higher cortical circuits. Clinicopathological observations have led to suspicions that the hypothalamus is directly involved in the production of laughter. In this functional magnetic resonance imaging investigation, healthy participants were 1) tickled on the sole of the right foot with permission to laugh, 2) tickled but asked to stifle laughter, and 3) requested to laugh voluntarily. Tickling that was accompanied by involuntary laughter activated regions in the lateral hypothalamus, parietal operculum, amygdala, and right cerebellum to a consistently greater degree than did the 2 other conditions. Activation of the periaqueductal gray matter was observed during voluntary and involuntary laughter but not when laughter was inhibited. The present findings indicate that hypothalamic activity plays a crucial role in evoking ticklish laughter in healthy individuals. The hypothalamus promotes innate behavioral reactions to stimuli and sends projections to the periaqueductal gray matter, which is itself an important integrative center for the control of vocalization. A comparison of our findings with published data relating to humorous laughter revealed the involvement of a common set of subcortical centers

In analogy to the appreciation of humor, that of tickling is based upon the re- interpretation of an anticipated emotional situation. Hence, the anticipation of tickling contributes to the final outburst of ticklish laughter. To localize the neuronal substrates of this process, fMRI was conducted on 31 healthy volunteers. The state of anticipation was simulated by generating an uncertainty respecting the onset of manual foot tickling. Anticipation was characterized by an augmented fMRI- signal in the anterior insula, the hypothalamus, the nucleus accumbens and the ventral tegmental area, as well as by an attenuated one in the internal globus pallidus. Furthermore, anticipatory activity in the anterior insula correlated positively with the degree of laughter that was produced during tickling. These findings are consistent with an encoding of the expected emotional consequences of tickling and suggest that early regulatory mechanisms influence, automatically, the laughter circuitry at the level of affective and sensory processing. Tickling activated not only those regions of the brain that were involved during anticipation, but also the posterior insula, the anterior cingulate cortex and the periaqueductal gray matter. Sequential or combined anticipatory and tickling-related neuronal activities may adjust emotional- and sensorimotor pathways in preparation for the impending laughter response.

The burst of laughter that is evoked by tickling is a primitive form of vocalization. It evolves during an early phase of postnatal life and appears to be independent of higher cortical circuits. Clinicopathological observations have led to suspicions that the hypothalamus is directly involved in the production of laughter. In this functional magnetic resonance imaging investigation, healthy participants were 1) tickled on the sole of the right foot with permission to laugh, 2) tickled but asked to stifle laughter, and 3) requested to laugh voluntarily. Tickling that was accompanied by involuntary laughter activated regions in the lateral hypothalamus, parietal operculum, amygdala, and right cerebellum to a consistently greater degree than did the 2 other conditions. Activation of the periaqueductal gray matter was observed during voluntary and involuntary laughter but not when laughter was inhibited. The present findings indicate that hypothalamic activity plays a crucial role in evoking ticklish laughter in healthy individuals. The hypothalamus promotes innate behavioral reactions to stimuli and sends projections to the periaqueductal gray matter, which is itself an important integrative center for the control of vocalization. A comparison of our findings with published data relating to humorous laughter revealed the involvement of a common set of subcortical centers.

The insular cortex is fundamentally involved in the processing of interoceptive information. It has been postulated that the integrative monitoring of the bodily responses to environmental stimuli is crucial for the recognition and experience of emotions. Because emotional arousal is known to be closely coupled to functions of the anterior insula, we suspected laughter to be associated primarily with neuronal activity in this region. An anatomically constrained re-analysis of our imaging data pertaining to ticklish laughter, to inhibited ticklish laughter, and to voluntary laughter revealed regional differences in the levels of neuronal activity in the posterior and mid-/anterior portions of the insula. Ticklish laughter was associated specifically with right ventral anterior insular activity, which was not detected under the other two conditions. Hence, apparently, only laughter that is evoked as an emotional response bears the signature of autonomic arousal in the insular cortex.