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1.
Nat Commun ; 12(1): 771, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536422

RESUMO

Many animals use the Earth's geomagnetic field for orientation and navigation. Yet, the molecular and cellular underpinnings of the magnetic sense remain largely unknown. A biophysical model proposed that magnetoreception can be achieved through quantum effects of magnetically-sensitive radical pairs formed by the photoexcitation of cryptochrome (CRY) proteins. Studies in Drosophila are the only ones to date to have provided compelling evidence for the ultraviolet (UV)-A/blue light-sensitive type 1 CRY (CRY1) involvement in animal magnetoreception, and surprisingly extended this discovery to the light-insensitive mammalian-like type 2 CRYs (CRY2s) of both monarchs and humans. Here, we show that monarchs respond to a reversal of the inclination of the Earth's magnetic field in an UV-A/blue light and CRY1, but not CRY2, dependent manner. We further demonstrate that both antennae and eyes, which express CRY1, are magnetosensory organs. Our work argues that only light-sensitive CRYs function in animal light-dependent inclination-based magnetic sensing.


Assuntos
Borboletas/fisiologia , Criptocromos/metabolismo , Proteínas de Insetos/metabolismo , Campos Magnéticos , Orientação/fisiologia , Sensação/fisiologia , Sequência de Aminoácidos , Animais , Antenas de Artrópodes/fisiologia , Antenas de Artrópodes/efeitos da radiação , Borboletas/genética , Borboletas/efeitos da radiação , Criptocromos/genética , Olho/efeitos da radiação , Humanos , Proteínas de Insetos/genética , Luz , Mutação , Orientação/efeitos da radiação , Sensação/genética , Sensação/efeitos da radiação , Homologia de Sequência de Aminoácidos
2.
Nature ; 533(7601): 52-7, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27120164

RESUMO

The primary visual cortex contains a detailed map of the visual scene, which is represented according to multiple stimulus dimensions including spatial location, ocular dominance and stimulus orientation. The maps for spatial location and ocular dominance arise from the spatial arrangement of thalamic afferent axons in the cortex. However, the origins of the other maps remain unclear. Here we show that the cortical maps for orientation, direction and retinal disparity in the cat (Felis catus) are all strongly related to the organization of the map for spatial location of light (ON) and dark (OFF) stimuli, an organization that we show is OFF-dominated, OFF-centric and runs orthogonal to ocular dominance columns. Because this ON-OFF organization originates from the clustering of ON and OFF thalamic afferents in the visual cortex, we conclude that all main features of visual cortical topography, including orientation, direction and retinal disparity, follow a common organizing principle that arranges thalamic axons with similar retinotopy and ON-OFF polarity in neighbouring cortical regions.


Assuntos
Mapeamento Encefálico , Percepção Espacial/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia , Vias Aferentes/efeitos da radiação , Animais , Axônios/fisiologia , Gatos , Escuridão , Dominância Ocular/fisiologia , Luz , Macaca mulatta , Masculino , Modelos Neurológicos , Orientação/fisiologia , Orientação/efeitos da radiação , Estimulação Luminosa , Retina/fisiologia , Retina/efeitos da radiação , Percepção Espacial/efeitos da radiação , Tálamo/fisiologia , Tálamo/efeitos da radiação , Córtex Visual/efeitos da radiação
3.
PLoS One ; 10(8): e0135213, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308915

RESUMO

Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history, larvae of coastal species have to head back to the shore at the end of their pelagic episode, to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence of coast-related cues on orientation. In this study we quantified the in situ orientation behavior of settlement-stage larvae in a temperate region, with a continuous coast and a dominant along-shore current, and inspected both coast-dependent and independent cues. We tested six species: one Pomacentridae, Chromis chromis, and five Sparidae, Boops boops, Diplodus annularis, Oblada melanura, Spicara smaris and Spondyliosoma cantharus. Over 85% of larvae were highly capable of keeping a bearing, which is comparable to the orientation abilities of tropical species. Sun-related cues influenced the precision of bearing-keeping at individual level. Three species, out of the four tested in sufficient numbers, oriented significantly relative to the sun position. These are the first in situ observations demonstrating the use of a sun compass for orientation by wild-caught settlement-stage larvae. This mechanism has potential for large-scale orientation of fish larvae globally.


Assuntos
Peixes/fisiologia , Orientação/efeitos da radiação , Luz Solar , Animais , Peixes/crescimento & desenvolvimento , Larva/fisiologia , Larva/efeitos da radiação , Estágios do Ciclo de Vida/fisiologia , Mar Mediterrâneo
4.
Proc Natl Acad Sci U S A ; 112(36): 11395-400, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26305929

RESUMO

Diurnal and nocturnal African dung beetles use celestial cues, such as the sun, the moon, and the polarization pattern, to roll dung balls along straight paths across the savanna. Although nocturnal beetles move in the same manner through the same environment as their diurnal relatives, they do so when light conditions are at least 1 million-fold dimmer. Here, we show, for the first time to our knowledge, that the celestial cue preference differs between nocturnal and diurnal beetles in a manner that reflects their contrasting visual ecologies. We also demonstrate how these cue preferences are reflected in the activity of compass neurons in the brain. At night, polarized skylight is the dominant orientation cue for nocturnal beetles. However, if we coerce them to roll during the day, they instead use a celestial body (the sun) as their primary orientation cue. Diurnal beetles, however, persist in using a celestial body for their compass, day or night. Compass neurons in the central complex of diurnal beetles are tuned only to the sun, whereas the same neurons in the nocturnal species switch exclusively to polarized light at lunar light intensities. Thus, these neurons encode the preferences for particular celestial cues and alter their weighting according to ambient light conditions. This flexible encoding of celestial cue preferences relative to the prevailing visual scenery provides a simple, yet effective, mechanism for enabling visual orientation at any light intensity.


Assuntos
Encéfalo/fisiologia , Besouros/fisiologia , Neurônios/fisiologia , Orientação/fisiologia , Animais , Encéfalo/citologia , Ritmo Circadiano/fisiologia , Besouros/efeitos da radiação , Sinais (Psicologia) , Ecossistema , Meio Ambiente , Luz , Lua , Atividade Motora/efeitos da radiação , Orientação/efeitos da radiação , Sistema Solar , Luz Solar
5.
Artigo em Inglês | MEDLINE | ID: mdl-25726016

RESUMO

The influence of salt concentration in the seawater on solar orientation in Talitrus saltator and Talorchestia ugolinii was studied in a confined environment (transparent plexiglass bowls). Sodium and calcium concentrations strongly affect both sea-land orientation and the sun compass mechanism in T.saltator, whereas the behaviour of T. ugolinii is less influenced. The absence of Na(+) does not influence the sun compass mechanism, but causes an inversion in the mean direction of orientation in T. saltator. In T. ugolinii, there was no influence on the compass mechanism for solar orientation and no inversion in the directional choice. In the absence of Ca(2+), a photonegative tendency was observed for T saltator together with marked reduction in the capacity to go in any direction. However, the effect of Ca(2+) absence on the orientation capacity of T. saltator is reversible and the orientation capacity can be reduced in a few minutes. The different behaviour of the two species of sandhoppers is discussed.


Assuntos
Anfípodes/fisiologia , Orientação , Cloreto de Sódio/farmacologia , Sistema Solar , Luz Solar , Animais , Cálcio/metabolismo , Orientação/efeitos dos fármacos , Orientação/fisiologia , Orientação/efeitos da radiação , Água do Mar/química , Especificidade da Espécie
6.
Bioelectromagnetics ; 36(1): 27-34, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25263937

RESUMO

Low-level radiofrequency (RF) signals may produce disorientation and nausea. In experiment I, we assessed mobile phone effects on graviception in nine symptomatic subjects after mobile telephone use and 21 controls. The mobile handset was strapped to each ear for 30 min in pulsed emission, continuous RF emission, or no emission test mode, respectively. The subjective visual vertical and horizontal (SVV/SVH) were tested from min 25 of exposure. There was no exposure effect; however, there was an ear effect, with the SVV/SVH being shifted to the opposite direction of the ear exposed. This could be due to thermal or RF effects or handset weight. In experiment II, we assessed the handset weight effect on 18 normal controls. After baseline SVV/SVH, the switched off handset was strapped to either ear; the SVV/SVH was repeated 25 min later. A significant ear effect was found. We compared the observed ear effect SVV/SVH change in the experiment II group to the continuous exposure ear effect change in the experiment I group, and the difference was not significant. The ear effect was attributed to a minor head tilt due to the handset weight, or proprioceptive stimulation of neck muscle affecting the perception of verticality.


Assuntos
Telefone Celular , Orientação , Percepção , Adulto , Orelha/fisiologia , Orelha/efeitos da radiação , Feminino , Gravitação , Humanos , Masculino , Pessoa de Meia-Idade , Orientação/fisiologia , Orientação/efeitos da radiação , Percepção/fisiologia , Percepção/efeitos da radiação , Estimulação Física , Ondas de Rádio , Radiometria , Inquéritos e Questionários , Temperatura , Adulto Jovem
7.
J R Soc Interface ; 11(97): 20140451, 2014 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-24942848

RESUMO

We report on the experiments on orientation of a migratory songbird, the garden warbler (Sylvia borin), during the autumn migration period on the Courish Spit, Eastern Baltics. Birds in experimental cages, deprived of visual information, showed the seasonally appropriate direction of intended flight with respect to the magnetic meridian. Weak radiofrequency (RF) magnetic field (190 nT at 1.4 MHz) disrupted this orientation ability. These results may be considered as an independent replication of earlier experiments, performed by the group of R. and W. Wiltschko with European robins (Erithacus rubecula). Confirmed outstanding sensitivity of the birds' magnetic compass to RF fields in the lower megahertz range demands for a revision of one of the mainstream theories of magnetoreception, the radical-pair model of birds' magnetic compass.


Assuntos
Migração Animal/fisiologia , Migração Animal/efeitos da radiação , Campos Magnéticos , Orientação/fisiologia , Orientação/efeitos da radiação , Aves Canoras/fisiologia , Percepção Espacial/fisiologia , Animais , Relação Dose-Resposta à Radiação , Doses de Radiação , Ondas de Rádio , Estações do Ano , Percepção Espacial/efeitos da radiação
8.
J Biol Rhythms ; 29(2): 144-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24682208

RESUMO

The present investigation was aimed at testing whether the lizard sky polarization compass is time compensated. For this purpose, ruin lizards, Podarcis sicula, were both trained and tested for orientation inside a Morris water maze under clear skies with the sun not in view. During training, lizards showed a striking bimodal orientation along the training axis, demonstrating their capability of determining the symmetry plane of the sky polarization pattern and thus the use of polarization information in orientation. After reaching criteria, lizards were kept 7 days in a 6-h fast clock-shift treatment and then released with the sun not in view. Six-hour clock-shifted lizards showed a bimodal distribution of directional choices, which was oriented perpendicularly to the training axis, as it was expected on the basis of the clock-shift. The results show that the only celestial diurnal compass mechanism that does not need a direct vision of the sun disk (i.e., the sky polarization compass) is a time-compensated compass.


Assuntos
Ritmo Circadiano/fisiologia , Lagartos/fisiologia , Orientação/fisiologia , Comportamento Espacial/fisiologia , Animais , Aprendizagem em Labirinto/fisiologia , Orientação/efeitos da radiação , Percepção Espacial/fisiologia , Comportamento Espacial/efeitos da radiação , Luz Solar
9.
PLoS One ; 9(3): e92109, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24647586

RESUMO

Zebrafish (Danio rerio) offer advantages as model animals for studies of inner ear development, genetics and ototoxicity. However, traditional assessment of vestibular function in this species using the vestibulo-ocular reflex requires agar-immobilization of individual fish and specialized video, which are difficult and labor-intensive. We report that using a static magnetic field to directly stimulate the zebrafish labyrinth results in an efficient, quantitative behavioral assay in free-swimming fish. We recently observed that humans have sustained nystagmus in high strength magnetic fields, and we attributed this observation to magnetohydrodynamic forces acting on the labyrinths. Here, fish were individually introduced into the center of a vertical 11.7T magnetic field bore for 2-minute intervals, and their movements were tracked. To assess for heading preference relative to a magnetic field, fish were also placed in a horizontally oriented 4.7T magnet in infrared (IR) light. A sub-population was tested again in the magnet after gentamicin bath to ablate lateral line hair cell function. Free-swimming adult zebrafish exhibited markedly altered swimming behavior while in strong static magnetic fields, independent of vision or lateral line function. Two-thirds of fish showed increased swimming velocity or consistent looping/rolling behavior throughout exposure to a strong, vertically oriented magnetic field. Fish also demonstrated altered swimming behavior in a strong horizontally oriented field, demonstrating in most cases preferred swimming direction with respect to the field. These findings could be adapted for 'high-throughput' investigations of the effects of environmental manipulations as well as for changes that occur during development on vestibular function in zebrafish.


Assuntos
Campos Magnéticos , Natação/fisiologia , Vestíbulo do Labirinto/fisiologia , Peixe-Zebra/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/efeitos da radiação , Feminino , Gentamicinas/farmacologia , Raios Infravermelhos , Locomoção/efeitos dos fármacos , Locomoção/efeitos da radiação , Masculino , Fenômenos Ópticos , Orientação/efeitos dos fármacos , Orientação/efeitos da radiação , Vestíbulo do Labirinto/efeitos dos fármacos
10.
Nat Neurosci ; 16(9): 1331-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23872595

RESUMO

Visual cortical neurons fire at higher rates to visual stimuli during locomotion than during immobility, while maintaining orientation selectivity. The mechanisms underlying this change in gain are not understood. We performed whole-cell recordings from layer 2/3 and layer 4 visual cortical excitatory neurons and from parvalbumin-positive and somatostatin-positive inhibitory neurons in mice that were free to rest or run on a spherical treadmill. We found that the membrane potential of all cell types became more depolarized and (with the exception of somatostatin-positive interneurons) less variable during locomotion. Cholinergic input was essential for maintaining the unimodal membrane potential distribution during immobility, whereas noradrenergic input was necessary for the tonic depolarization associated with locomotion. Our results provide a mechanism for how neuromodulation controls the gain and signal-to-noise ratio of visual cortical neurons during changes in the state of vigilance.


Assuntos
Modelos Neurológicos , Neurônios/fisiologia , Orientação/fisiologia , Córtex Visual/citologia , Vias Visuais/fisiologia , Potenciais de Ação/fisiologia , Animais , Proteínas de Ligação a DNA/genética , Feminino , Imobilização , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/classificação , Neurônios/efeitos dos fármacos , Neurotransmissores/farmacologia , Orientação/efeitos dos fármacos , Orientação/efeitos da radiação , Parvalbuminas/genética , Técnicas de Patch-Clamp , Estimulação Luminosa , Razão Sinal-Ruído , Fatores de Transcrição/genética , Córtex Visual/fisiologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-23848712

RESUMO

The radical-pair mechanism is one of two distinct mechanisms used to explain the navigation of birds in geomagnetic fields, however little research has been done to explore the role of quantum entanglement in this mechanism. In this paper we study the lifetime of radical-pair entanglement corresponding to the magnitude and direction of magnetic fields to show that the entanglement lasts long enough in birds to be used for navigation. We also find that the birds appear to not be able to orient themselves directly based on radical-pair entanglement due to a lack of orientation sensitivity of the entanglement in the geomagnetic field. To explore the entanglement mechanism further, we propose a model in which the hyperfine interactions are replaced by local magnetic fields of similar strength. The entanglement of the radical pair in this model lasts longer and displays an angular sensitivity in weak magnetic fields, both of which are not present in previous models.


Assuntos
Migração Animal/fisiologia , Migração Animal/efeitos da radiação , Aves/fisiologia , Voo Animal/fisiologia , Modelos Biológicos , Orientação/fisiologia , Orientação/efeitos da radiação , Animais , Simulação por Computador , Voo Animal/efeitos da radiação , Campos Magnéticos , Teoria Quântica
12.
Proc Biol Sci ; 280(1763): 20130853, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23720547

RESUMO

The avian magnetic compass works in a fairly narrow functional window around the intensity of the local geomagnetic field, but adjusts to intensities outside this range when birds experience these new intensities for a certain time. In the past, the geomagnetic field has often been much weaker than at present. To find out whether birds can obtain directional information from a weak magnetic field, we studied spontaneous orientation preferences of migratory robins in a 4 µT field (i.e. a field of less than 10 per cent of the local intensity of 47 µT). Birds can adjust to this low intensity: they turned out to be disoriented under 4 µT after a pre-exposure time of 8 h to 4 µT, but were able to orient in this field after a total exposure time of 17 h. This demonstrates a considerable plasticity of the avian magnetic compass. Orientation in the 4 µT field was not affected by local anaesthesia of the upper beak, but was disrupted by a radiofrequency magnetic field of 1.315 MHz, 480 nT, suggesting that a radical-pair mechanism still provides the directional information in the low magnetic field. This is in agreement with the idea that the avian magnetic compass may have developed already in the Mesozoic in the common ancestor of modern birds.


Assuntos
Voo Animal/fisiologia , Fenômenos Magnéticos , Orientação/fisiologia , Aves Canoras/fisiologia , Migração Animal , Animais , Bico/fisiologia , Bico/efeitos da radiação , Aves , Campos Magnéticos , Orientação/efeitos da radiação , Ondas de Rádio
13.
Artigo em Inglês | MEDLINE | ID: mdl-23111859

RESUMO

Iron-rich structures have been described in the beak of homing pigeons, chickens and several species of migratory birds and interpreted as magnetoreceptors. Here, we will briefly review findings associated with these receptors that throw light on their nature, their function and their role in avian navigation. Electrophysiological recordings from the ophthalmic nerve, behavioral studies and a ZENK-study indicate that the trigeminal system, the nerves innervating the beak, mediate information on magnetic changes, with the electrophysiological study suggesting that these are changes in intensity. Behavioral studies support the involvement of magnetite and the trigeminal system in magnetoreception, but clearly show that the inclination compass normally used by birds represents a separate system. However, if this compass is disrupted by certain light conditions, migrating birds show 'fixed direction' responses to the magnetic field, which originate in the receptors in the beak. Together, these findings point out that there are magnetite-based magnetoreceptors located in the upper beak close to the skin. Their natural function appears to be recording magnetic intensity and thus providing one component of the multi-factorial 'navigational map' of birds.


Assuntos
Bico/fisiologia , Aves/fisiologia , Óxido Ferroso-Férrico/metabolismo , Campos Magnéticos , Orientação/fisiologia , Células Receptoras Sensoriais/fisiologia , Nervo Trigêmeo/fisiologia , Vias Aferentes/fisiologia , Vias Aferentes/efeitos da radiação , Animais , Bico/inervação , Bico/efeitos da radiação , Magnetometria/métodos , Orientação/efeitos da radiação , Células Receptoras Sensoriais/efeitos da radiação , Nervo Trigêmeo/efeitos da radiação
15.
Bull Exp Biol Med ; 153(6): 816-9, 2012 Oct.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-23113292

RESUMO

Single exposure of white outbred rats to electromagnetic radiation with a frequency 905 MHz (GSM frequency) for 2 h increased anxiety, reduced locomotor, orientation, and exploration activities in females and orientation and exploration activities in males. Glucocorticoid levels and antioxidant system activity increased in both males and females. In addition to acute effects, delayed effects of radiation were observed in both males and females 1 day after the exposure. These results demonstrated significant effect of GSM-range radiation on the behavior and activity of stress-realizing and stress-limiting systems of the body.


Assuntos
Ansiedade/sangue , Radiação Eletromagnética , Comportamento Exploratório/efeitos da radiação , Reação de Congelamento Cataléptica/efeitos da radiação , Atividade Motora/efeitos da radiação , Orientação/efeitos da radiação , Adulto , Animais , Animais não Endogâmicos , Antioxidantes/metabolismo , Ansiedade/fisiopatologia , Telefone Celular , Feminino , Glucocorticoides/sangue , Humanos , Masculino , Ratos
16.
J Exp Biol ; 215(Pt 19): 3478-87, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22735352

RESUMO

Edges represent important information in object recognition, and thus edge detection is crucial for animal survival. Various types of edges result from visual contrast, such as luminance contrast and color contrast. So far, the molecular and neural mechanisms underlying edge detection and the relationship between different edge information-processing pathways have been largely undemonstrated. In the present study, using a color light-emitting-diode-based Buridan's paradigm, we demonstrated that a blue/green demarcation is able to generate edge-orientation behavior in the adult fly. There is a blue/green intensity ratio, the so-called point of equal luminance, at which wild-type flies did not show obvious orientation behavior towards edges. This suggests that orientation behavior towards edges is dependent on luminance contrast in Drosophila. The results of mutants ninaE(17) and sev(LY3);rh5(2);rh6(1) demonstrated that achromatic R1-R6 photoreceptor cells, but not chromatic R7/R8 photoreceptor cells, were necessary for orientation behavior towards edges. Moreover, ectopic expression of rhodopsin 4 (Rh4), Rh5 or Rh6 could efficiently restore the edge-orientation defect in the ninaE(17) mutant. Altogether, our results show that R1-R6 photoreceptor cells are both necessary and sufficient for orientation behavior towards edges in Drosophila.


Assuntos
Sensibilidades de Contraste/fisiologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/efeitos da radiação , Luz , Animais , Comportamento Animal/fisiologia , Visão de Cores/fisiologia , Visão de Cores/efeitos da radiação , Sensibilidades de Contraste/efeitos da radiação , Orientação/fisiologia , Orientação/efeitos da radiação , Células Fotorreceptoras de Invertebrados/fisiologia , Células Fotorreceptoras de Invertebrados/efeitos da radiação , Rodopsina/metabolismo
17.
J Exp Biol ; 215(Pt 18): 3200-6, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22693032

RESUMO

The present study first examined whether ruin lizards, Podarcis sicula, are able to orientate using plane-polarized light produced by an LCD screen. Ruin lizards were trained and tested indoors, inside a hexagonal Morris water maze positioned under an LCD screen producing white polarized light with a single E-vector, which provided an axial cue. White polarized light did not include wavelengths in the UV. Lizards orientated correctly either when tested with E-vector parallel to the training axis or after 90 deg rotation of the E-vector direction, thus validating the apparatus. Further experiments examined whether there is a preferential region of the light spectrum to perceive the E-vector direction of polarized light. For this purpose, lizards reaching learning criteria under white polarized light were subdivided into four experimental groups. Each group was tested for orientation under a different spectrum of plane-polarized light (red, green, cyan and blue) with equalized photon flux density. Lizards tested under blue polarized light orientated correctly, whereas lizards tested under red polarized light were completely disoriented. Green polarized light was barely discernible by lizards, and thus insufficient for a correct functioning of their compass. When exposed to cyan polarized light, lizard orientation performances were optimal, indistinguishable from lizards detecting blue polarized light. Overall, the present results demonstrate that perception of linear polarization in the blue is necessary - and sufficient - for a proper functioning of the sky polarization compass of ruin lizards. This may be adaptively important, as detection of polarized light in the blue improves functioning of the polarization compass under cloudy skies, i.e. when the alternative celestial compass based on detection of the sun disk is rendered useless because the sun is obscured by clouds.


Assuntos
Luz , Lagartos/fisiologia , Orientação/fisiologia , Orientação/efeitos da radiação , Animais , Comportamento Animal/fisiologia , Comportamento Animal/efeitos da radiação , Cor , Itália , Reprodutibilidade dos Testes
18.
Int Rev Psychiatry ; 23(5): 413-23, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22200131

RESUMO

Magnetic seizure therapy (MST) is a novel neurotherapeutic intervention in development for the treatment of major affective disorders. Like other neurotherapeutic strategies such as electroconvulsive therapy (ECT) or transcranial magnetic stimulation (TMS), a primary interest will be to monitor the associated neurocognitive effects. Thus, the purpose of this systematic review was to synthesize the available data on the neurocognitive effects of MST. The authors performed two independent literature searches with the following terms terms: MST, magnetic, magnetic seizure therapy, depression, neurocognition, cognitive, preclinical. We included in this review a total of eleven articles that mentioned MST and neurocognition in the abstract. The articles were divided into three methodological domains that included virtual computer simulations, preclinical studies, and clinical investigations. Collectively, the available evidence suggests MST has little to no adverse cognitive effects. Specifically, virtual computer simulations found the magnetic field was localized to grey matter, and preclinical studies found no neurocortical or neurocognitive sequelae. Clinical investigations found MST to be associated with rapid reorientation and intact anterograde and retrograde memory. Future investigations using translational methods are warranted to confirm these findings and to further determine the effects of MST on neurocognitive functions.


Assuntos
Cognição/efeitos da radiação , Memória/efeitos da radiação , Transtornos do Humor/terapia , Orientação/efeitos da radiação , Estimulação Magnética Transcraniana , Simulação por Computador/tendências , Aprovação de Equipamentos , Humanos , Modelos Neurológicos , Modelos Psicológicos , Monitorização Fisiológica/métodos , Transtornos do Humor/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Convulsões/etiologia , Terapias em Estudo/instrumentação , Terapias em Estudo/métodos , Estimulação Magnética Transcraniana/instrumentação , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Interface Usuário-Computador
19.
PLoS One ; 6(6): e20990, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21695167

RESUMO

Orientation of insects to host plants and conspecifics is the result of detection and integration of chemical and physical cues present in the environment. Sensory organs have evolved to be sensitive to important signals, providing neural input for higher order multimodal processing and behavioral output. Here we report experiments to determine decisions made by Colorado potato beetle (CPB), Leptinotarsa decemlineata, in response to isolated stimuli and multimodal combinations of signals on a locomotion compensator. Our results show that in complete darkness and in the absence of other stimuli, pheromonal stimulation increases attraction behavior of CPB as measured in oriented displacement and walking speed. However, orientation to the pheromone is abolished when presented with the alternative stimulation of a low intensity yellow light in a dark environment. The ability of the pheromone to stimulate these diurnal beetles in the dark in the absence of other stimuli is an unexpected but interesting observation. The predominance of the phototactic response over that to pheromone when low intensity lights were offered as choices seems to confirm the diurnal nature of the insect. The biological significance of the response to pheromone in the dark is unclear. The phototactic response will play a key role in elucidating multimodal stimulation in the host-finding process of CPB, and perhaps other insects. Such information might be exploited in the design of applications to attract and trap CPB for survey or control purposes and other insect pests using similar orientation mechanisms.


Assuntos
Besouros/metabolismo , Besouros/efeitos da radiação , Luz , Feromônios/metabolismo , Animais , Comportamento Animal/efeitos da radiação , Besouros/fisiologia , Cor , Escuridão , Feminino , Masculino , Atividade Motora/efeitos da radiação , Orientação/efeitos da radiação
20.
Nature ; 471(7340): E11-2; discussion E12-3, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21455128

RESUMO

Arising from W. Wiltschko et al. 419, 467-470 (2002); Wiltschko et al. replyThe magnetic compass of migratory birds is embedded in the visual system and it has been reported by Wiltschko et al. that European Robins, Erithacus rubecula, cannot show magnetic compass orientation using their left eye only. This has led to the notion that the magnetic compass should be located only in the right eye of birds. However, a complete right lateralization of the magnetic compass would be very surprising, and functional neuroanatomical data have questioned this notion. Here we show that the results of Wiltschko et al. could not be independently confirmed using double-blind protocols. European Robins can perform magnetic compass orientation with both eyes open, with the left eye open only, and with the right eye open only. No clear lateralization is observed.


Assuntos
Migração Animal/fisiologia , Olho , Magnetismo , Fenômenos Fisiológicos Oculares , Orientação/fisiologia , Aves Canoras/fisiologia , Migração Animal/efeitos da radiação , Animais , Olho/efeitos da radiação , Lateralidade Funcional/fisiologia , Modelos Biológicos , Fenômenos Fisiológicos Oculares/efeitos da radiação , Orientação/efeitos da radiação , Estimulação Luminosa , Reprodutibilidade dos Testes , Estações do Ano , Aves Canoras/anatomia & histologia
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