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1.
J Clin Aesthet Dermatol ; 12(5): 28-32, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31320974

RESUMO

Pyoderma gangrenosum (PG) is a rare, ulcerative, inflammatory skin disease that most commonly presents on the lower legs. Development of PG on the head and neck is exceedingly rare. We present the case of a 52-year-old man with no known history of underlying systemic disease who developed multiple facial lesions of PG that were refractory to both standard and alternative treatment modalities. Clearance of disease was ultimately achieved using adalimumab.

2.
Med Hypotheses ; 83(5): 614-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25227333

RESUMO

Compelling new findings suggest that an early core signature of autism is a deficient left anterior temporal lobe response to language and an atypical over-activation of the right anterior temporal lobe. Intriguingly, our recent results from an entirely different line of reasoning and experiments also show that applying cathodal stimulation (suppressing) at the left anterior temporal lobe together with anodal stimulation (facilitating) at the right anterior temporal lobe, by transcranial direct current stimulation (tDCS), can induce some autistic-like cognitive abilities in otherwise normal adults. If we could briefly induce autistic like cognitive abilities in healthy individuals, it follows that we might be able to mitigate some autistic traits by reversing the above stimulation protocol, in an attempt to restore the typical dominance of the left anterior temporal lobe. Accordingly, we hypothesize that at least some autistic traits can be mitigated, by applying anodal stimulation (facilitating) at the left anterior temporal lobe together with cathodal stimulation (suppressing) at the right anterior temporal lobe. Our hypothesis is supported by strong convergent evidence that autistic symptoms can emerge and later reverse due to the onset and subsequent recovery of various temporal lobe (predominantly the left) pathologies. It is also consistent with evidence that the temporal lobes (especially the left) are a conceptual hub, critical for extracting meaning from lower level sensory information to form a coherent representation, and that a deficit in the temporal lobes underlies autistic traits.


Assuntos
Transtorno Autístico/fisiopatologia , Transtorno Autístico/terapia , Estimulação Elétrica/métodos , Lobo Temporal/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletrodos , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Testes Neuropsicológicos
4.
Sci Rep ; 2: 502, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22792435

RESUMO

The earliest stages in our perception of the world have a subtle but powerful influence on later thought processes; they provide the contextual cues within which our thoughts are framed and they adapt to many different environments throughout our lives. Understanding the changes in these cues is crucial to understanding how our perceptual ability develops, but these changes are often difficult to quantify in sufficiently complex tasks where objective measures of development are available. Here we simulate perceptual learning using neural networks and demonstrate fundamental changes in these cues as a function of skill. These cues are cognitively grouped together to form perceptual templates that enable rapid 'whole scene' categorisation of complex stimuli. Such categories reduce the computational load on our capacity limited thought processes, they inform our higher cognitive processes and they suggest a framework of perceptual pre-processing that captures the central role of perception in expertise.


Assuntos
Sinais (Psicologia) , Modelos Teóricos , Redes Neurais de Computação , Percepção , Generalização do Estímulo , Humanos , Aprendizagem
5.
Neurosci Lett ; 515(2): 121-4, 2012 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-22440856

RESUMO

Certain problems are inherently difficult for the normal human mind. Yet paradoxically they can be effortless for those with an unusual mind. We discovered that an atypical protocol for non-invasive brain stimulation enabled the solution of a problem that was previously unsolvable. The majority of studies over the last century find that no participants can solve the nine-dot problem - a fact we confirmed. But with 10 min of right lateralising transcranial direct current stimulation (tDCS), more than 40% of participants did so. Specifically, whereas no participant solved this extremely difficult problem before stimulation or with sham stimulation, 14 out of 33 participants did so with cathodal stimulation of the left anterior temporal lobe together with anodal stimulation of the right anterior temporal lobe. This finding suggests that our stimulation paradigm might be helpful for mitigating cognitive biases or dealing with a broader class of tasks that, although deceptively simple, are nonetheless extremely difficult due to our cognitive makeup.


Assuntos
Encéfalo/fisiologia , Estimulação Elétrica , Resolução de Problemas/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Neuropsychology ; 25(2): 185-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21381825

RESUMO

OBJECTIVE: Inhibiting the anterior temporal lobe (ATL) via repetitive transcranial magnetic stimulation (rTMS) appears to have deleterious effects on people's semantic conceptualization, and left ATL damage is associated with semantic dementia. However, little research has investigated whether rTMS can inhibit conceptual schemata that have potentially negative consequences. Our aim was to investigate whether rTMS to the ATLs could reduce scores on a standard measure of prejudice (implicit association test, IAT). METHOD: Forty (17 female; mean age 20.6) neurologically normal, right-handed undergraduates participated. Participants were randomly allocated into one of four rTMS stimulation conditions-left ATL, right ATL, control site (motor cortex, Cz), and sham stimulation. All participants completed a modified IAT, where "good" and "bad" words were replaced with "terrorist" and "law-abider" words, and, "Black" and "White" were replaced with "Arab" and "Non-Arab" words. Participants were then given 15 min of rTMS stimulation. Afterward, participants completed a parallel form of the IAT. RESULTS: To investigate the effects of rTMS on IAT scores, a one-way ANOVA on the difference between pre- and postscores was carried out revealing that there were significant between group differences (F3,36 = 3.57; p = .02). Planned contrasts revealed that both left and right ATL stimulation significantly reduced IAT scores poststimulation, indicating lower prejudice. CONCLUSION: We show that prejudice scores can be significantly reduced by inhibitory rTMS delivered to the bilateral ATLs. This may implicate this area in conceptual associations that lead to overgeneralization and stereotyping of social groups.


Assuntos
Preconceito , Lobo Temporal/fisiologia , Lobo Temporal/efeitos da radiação , Estimulação Magnética Transcraniana , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Testes Psicológicos , Tempo de Reação/efeitos da radiação , Semântica , Inquéritos e Questionários , Adulto Jovem
7.
PLoS One ; 6(2): e16655, 2011 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-21311746

RESUMO

Our experiences can blind us. Once we have learned to solve problems by one method, we often have difficulties in generating solutions involving a different kind of insight. Yet there is evidence that people with brain lesions are sometimes more resistant to this so-called mental set effect. This inspired us to investigate whether the mental set effect can be reduced by non-invasive brain stimulation. 60 healthy right-handed participants were asked to take an insight problem solving task while receiving transcranial direct current stimulation (tDCS) to the anterior temporal lobes (ATL). Only 20% of participants solved an insight problem with sham stimulation (control), whereas 3 times as many participants did so (p = 0.011) with cathodal stimulation (decreased excitability) of the left ATL together with anodal stimulation (increased excitability) of the right ATL. We found hemispheric differences in that a stimulation montage involving the opposite polarities did not facilitate performance. Our findings are consistent with the theory that inhibition to the left ATL can lead to a cognitive style that is less influenced by mental templates and that the right ATL may be associated with insight or novel meaning. Further studies including neurophysiological imaging are needed to elucidate the specific mechanisms leading to the enhancement.


Assuntos
Melhoramento Biomédico/métodos , Encéfalo/fisiologia , Estimulação Elétrica , Resolução de Problemas/fisiologia , Adolescente , Adulto , Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos , Feminino , Humanos , Masculino , Matemática , Modelos Biológicos , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
8.
Brain Res ; 1353: 168-75, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20682299

RESUMO

Our visual memories are susceptible to errors, but less so in people who have a more literal cognitive style. This inspired us to attempt to improve visual memory with non-invasive brain stimulation. We applied 13 min of bilateral transcranial direct current stimulation (tDCS) to the anterior temporal lobes. Our stimulation protocol included 3 conditions, each with 12 neurotypical participants: (i) left cathodal stimulation together with right anodal stimulation, (ii) left anodal stimulation together with right cathodal stimulation, and (iii) sham (control) stimulation. Only participants who received left cathodal stimulation (decrease in excitability) together with right anodal stimulation (increase in excitability) showed an improvement in visual memory. This 110% improvement in visual memory was similar to the advantage people with autism, who are known to be more literal, show over normal people in the identical visual task. Importantly, participants receiving stimulation of the opposite polarity (left anodal together with right cathodal stimulation) failed to show any change in memory performance. This is the first demonstration that visual memory can be enhanced in healthy people using non-invasive brain stimulation.


Assuntos
Encéfalo/fisiologia , Memória/fisiologia , Estimulação Magnética Transcraniana/métodos , Percepção Visual/fisiologia , Adolescente , Adulto , Análise de Variância , Biofísica/métodos , Estimulação Elétrica/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa/métodos , Detecção de Sinal Psicológico/fisiologia , Adulto Jovem
9.
Philos Trans R Soc Lond B Biol Sci ; 364(1522): 1399-405, 2009 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-19528023

RESUMO

I argue that savant skills are latent in us all. My hypothesis is that savants have privileged access to lower level, less-processed information, before it is packaged into holistic concepts and meaningful labels. Owing to a failure in top-down inhibition, they can tap into information that exists in all of our brains, but is normally beyond conscious awareness. This suggests why savant skills might arise spontaneously in otherwise normal people, and why such skills might be artificially induced by low-frequency repetitive transcranial magnetic stimulation. It also suggests why autistic savants are atypically literal with a tendency to concentrate more on the parts than on the whole and why this offers advantages for particular classes of problem solving, such as those that necessitate breaking cognitive mindsets. A strategy of building from the parts to the whole could form the basis for the so-called autistic genius. Unlike the healthy mind, which has inbuilt expectations of the world (internal order), the autistic mind must simplify the world by adopting strict routines (external order).


Assuntos
Aptidão/fisiologia , Cognição/fisiologia , Modelos Psicológicos , Lobo Temporal/fisiologia , Estimulação Magnética Transcraniana/métodos , Humanos , Resolução de Problemas/fisiologia
10.
PLoS One ; 4(3): e4959, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19319182

RESUMO

A recent study found that false memories were reduced by 36% when low frequency repetitive transcranial magnetic stimulation (rTMS) was applied to the left anterior temporal lobe after the encoding (study) phase. Here we were interested in the consequences on a false memory task of brain stimulation throughout the encoding and retrieval task phases. We used transcranial direct current stimulation (tDCS) because it has been shown to be a useful tool to enhance cognition. Specifically, we examined whether tDCS can induce changes in a task assessing false memories. Based on our preliminary results, three conditions of stimulation were chosen: anodal left/cathodal right anterior temporal lobe (ATL) stimulation ("bilateral stimulation"); anodal left ATL stimulation (with a large contralateral cathodal electrode--referred as "unilateral stimulation") and sham stimulation. Our results showed that false memories were reduced significantly after the two active conditions (unilateral and bilateral stimulation) as compared with sham stimulation. There were no significant changes in veridical memories. Our findings show that false memories are reduced by 73% when anodal tDCS is applied to the anterior temporal lobes throughout the encoding and retrieval stages, suggesting a possible strategy for improving certain aspects of learning.


Assuntos
Estimulação Elétrica , Memória/fisiologia , Lobo Temporal/fisiologia , Estimulação Magnética Transcraniana , Adolescente , Feminino , Humanos , Aprendizagem , Masculino , Adulto Jovem
11.
Neurosci Lett ; 449(3): 151-4, 2009 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-19022348

RESUMO

False memories are ubiquitous and often to our detriment. Yet, certain pathologies, including anterior temporal lobe dementia and autism, can lead to literal recall and thus greater resistance to false memories. This inspired us to reduce false memories by temporarily inhibiting the left anterior temporal lobe, using low frequency magnetic pulse stimulation. This site has been implicated in semantic memory and conceptual labelling. After active stimulation, participants in the sham/TMS group had 36% fewer false memories than they had with sham stimulation, and intact veridical memory. This is comparable to the improvement that people with autism and semantic dementia show over "normal" individuals. This finding suggests a potential method for reducing certain types of false memories.


Assuntos
Memória/fisiologia , Repressão Psicológica , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Semântica , Lobo Temporal/fisiologia , Adulto Jovem
13.
Perception ; 35(6): 837-45, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16836048

RESUMO

Oliver Sacks observed autistic twins who instantly guessed the exact number of matchsticks that had just fallen on the floor, saying in unison "111". To test the suggestion that normal individuals have the capacity for savant numerosity, we temporarily simulated the savant condition in normal people by inhibiting the left anterior temporal lobe of twelve participants with repetitive transcranial magnetic stimulation (rTMS). This site has been implicated in the savant condition. Ten participants improved their ability to accurately guess the number of discrete items immediately following rTMS and, of these, eight became worse at guessing as the effects of the pulses receded. The probability of as many as eight out of twelve people doing best just after rTMS and not after sham stimulation by chance alone is less than one in one thousand.


Assuntos
Cognição , Lobo Temporal , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Sensação , Percepção Visual
14.
J Integr Neurosci ; 5(2): 187-97, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16783868

RESUMO

The universality across cultures for recognizing the facial expression of anger suggests an evolved mechanism for dealing with threat. Using low frequency repetitive transcranial magnetic stimulation (rTMS) and a paradigm involving color-naming latencies for angry, fearful and neutral faces, and for emotional and neutral words respectively, we found evidence for a hemispheric specialization according to the sex and emotional content of faces in female subjects. Participants showed increased attention specifically to male angry faces after stimulation of the right superior temporal lobe, whereas they showed increased attention to angry female faces after left temporal stimulation. No effect was detected regarding the processing of fearful faces or emotional words. This result suggests differential processing of sex-specific threat-related stimuli specifically involving both hemispheres, i.e., that male and female faces are processed in opposite hemispheres, which might reflect the divergent adaptive significance of male and female threat for young females.


Assuntos
Ira/fisiologia , Encéfalo/fisiologia , Expressão Facial , Lateralidade Funcional/fisiologia , Caracteres Sexuais , Adolescente , Adulto , Análise de Variância , Atenção/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana/métodos
15.
Psychol Rep ; 94(3 Pt 2): 1325-30, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15362412

RESUMO

The recognition of the correct solution to a problem after a period when one is not actively searching for an answer is well documented. However, previous research has focused on problems an individual has not yet resolved. We presented a scenario in which 125 participants believed that they had completed a task and so had no reason to seek further solutions. To their surprise, after a period of distraction, we resumed the testing session. This novel method was combined with accurate recording of both response content and timing. The results from the second session a remarkable similarity n initial burst to those from the first, including a ideas, allowing the inference that, even in the absence of a reason to seek solutions, a process of nonconscious idea generation might be operating.


Assuntos
Atenção , Conscientização , Resolução de Problemas , Inconsciente Psicológico , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Motivação
16.
J Integr Neurosci ; 3(1): 31-46, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15139077

RESUMO

We advance a dominant neural strategy for facilitating conceptual thought. Concepts are groupings of "object" attributes. Once the brain learns such critical groupings, the "object" attributes are inhibited from conscious awareness. We see the whole, not the parts. The details are inhibited when the concept network is activated, ie. the inhibition is dynamic and can be switched on and off. Autism is suggested to be the state of retarded concept formation. Our model predicts the possibility of accessing nonconscious information by artificially disinhibiting (turning off) the inhibiting networks associated with concept formation, using transcranial magnetic brain stimulation (TMS). For example, this opens the door for the restoration of perfect pitch, for recalling detail, for acquiring accent-free second languages beyond puberty, and even for enhancing creativity. The model further shows how unusual autistic savant skills as well as certain psychopathologies can be due respectively to privileged or inadvertent access to information that is normally inhibited from conscious awareness.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Formação de Conceito/fisiologia , Estado de Consciência/fisiologia , Modelos Neurológicos , Adulto , Transtorno Autístico/fisiopatologia , Terapia por Estimulação Elétrica , Humanos , Lactente , Magnetismo , Inibição Neural/fisiologia
17.
J Integr Neurosci ; 2(2): 149-58, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15011267

RESUMO

The astonishing skills of savants have been suggested to be latent in everyone, but are not normally accessible without a rare form of brain impairment. We attempted to simulate such brain impairment in healthy people by directing low-frequency magnetic pulses into the left fronto-temporal lobe. Significant stylistic changes in drawing were facilitated by the magnetic pulses in four of our 11 participants. Some of these "facilitated" participants also displayed enhanced proofreading ability. Our conclusions are derived from 11 right-handed male university students, eight of whom underwent placebo stimulation. We examined performance before, during and after exposure to the stimulation.


Assuntos
Arte , Dominância Cerebral , Lobo Frontal/fisiologia , Lobo Temporal/fisiologia , Adulto , Estimulação Elétrica , Humanos , Magnetismo , Masculino , Destreza Motora/fisiologia , Percepção/fisiologia , Valores de Referência
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