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Introduction: The concept of affordance refers to the opportunities for action provided by the environment, often conveyed through visual information. It has been applied to explain visuomotor processing and movement planning. As emotion modulates both visual perception and the motor system, it is reasonable to ask whether emotion can influence affordance judgments. If present, this relationship can have important ontological implications for affordances. Thus, we investigated whether the emotional value of manipulable objects affected the judgment of the appropriate grasping that could be used to interact with them (i.e., their affordance). Methods: Volunteers were instructed to use a numerical scale to report their judgment on how an observed object should be grasped. We compared these judgments across emotional categories of objects (pleasant, unpleasant and neutral), while also considering the expected effect of object size. Results: We found that unpleasant objects were rated as more appropriately graspable by a precision grip than pleasant and neutral objects. Simultaneously, smaller object size also favored this judgment. This effect was seen in all emotional categories examined in equal magnitude. Discussion: Our findings suggest that the emotional value of objects modulates affordance judgments in a way that favors careful manipulation and minimal physical contact with aversive stimuli. Finally, we discuss how this affective aspect of our experience of objects overlaps with what affordances are conceptualized to be, calling for further reexamination of the relationship between affordances and emotions.

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Background: Traumatic brachial plexus injury (TBPI) causes a sensorimotor deficit in upper limb (UL) movements. Objective: Our aim was to investigate the arm-forearm coordination of both the injured and uninjured UL of TBPI subjects. Methods: TBPI participants (n = 13) and controls (n = 10) matched in age, gender, and anthropometric characteristics were recruited. Kinematics from the shoulder, elbow, wrist, and index finger markers were collected, while upstanding participants transported a cup to their mouth and returned the UL to a starting position. The UL coordination was measured through the relative phase (RP) between arm and forearm phase angles and analyzed as a function of the hand kinematics. Results: For all participants, the hand transport had a shorter time to peak velocity (p < 0.01) compared to the return. Also, for the control and the uninjured TBPI UL, the RP showed a coordination pattern that favored forearm movements in the peak velocity of the transport phase (p < 0.001). TBPI participants' injured UL showed a longer movement duration in comparison to controls (p < 0.05), but no differences in peak velocity, time to peak velocity, and trajectory length, indicating preserved hand kinematics. The RP of the injured UL revealed altered coordination in favor of arm movements compared to controls and the uninjured UL (p < 0.001). Finally, TBPI participants' uninjured UL showed altered control of arm and forearm phase angles during the deceleration of hand movements compared to controls (p < 0.05). Conclusion: These results suggest that UL coordination is reorganized after a TBPI so as to preserve hand kinematics.

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Background: Traumatic brachial plexus injury (TBPI) typically causes sensory, motor and autonomic deficits of the affected upper limb. Recent studies have suggested that a unilateral TBPI can also affect the cortical representations associated to the uninjured limb. Objective: To investigate the kinematic features of the uninjured upper limb in participants with TBPI. Methods: Eleven participants with unilateral TBPI and twelve healthy controls matched in gender, age and anthropometric characteristics were recruited. Kinematic parameters collected from the index finger marker were measured while participants performed a free-endpoint whole-body reaching task and a cup-to-mouth task with the uninjured upper limb in a standing position. Results: For the whole-body reaching task, lower time to peak velocity (p = 0.01), lower peak of velocity (p = 0.003), greater movement duration (p = 0.04) and shorter trajectory length (p = 0.01) were observed in the TBPI group compared to the control group. For the cup-to-mouth task, only a lower time to peak velocity was found for the TBPI group compared to the control group (p = 0.02). Interestingly, no differences between groups were observed for the finger endpoint height parameter in either of the tasks. Taken together, these results suggest that TBPI leads to a higher cost for motor planning when it comes to movements of the uninjured limb as compared to healthy participants. This cost is even higher in a task with a greater postural balance challenge. Conclusion: This study expands the current knowledge on bilateral sensorimotor alterations after unilateral TBPI and should guide rehabilitation after a peripheral injury.

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Individuals with stroke present several impairments in the ipsilesional arm reaching movements that can limit the execution of daily living activities. These impairments depend on the side of the brain lesion. The present study aimed to compare the arm reaching movements performed in sitting and standing positions and to examine whether the effects of the adopted posture configuration depend on the side of the brain lesion. Twenty right-handed individuals with stroke (half with right hemiparesis and a half with left hemiparesis) and twenty healthy adults (half used the left arm) reached toward a target displayed on a monitor screen placed in one of three heights (i.e., upper, central, or lower targets). Participants performed the reaches in sitting and standing positions under conditions where the target location was either well-known in advance (certainty condition) or unknown until the movement onset (uncertainty condition). The values of movement onset time, movement time, and constant error were compared across conditions (posture configuration and uncertainty) and groups for each target height. Individuals with stroke were slower and spent more time to start to move than healthy participants, mainly when they reached the superior target in the upright position and under the uncertainty condition. Individuals who have suffered a right stroke were more affected by the task conditions and those who suffered a left stroke showed less accurate reaches. Overall, these results were observed regardless of the adopted posture. The current findings suggested that ipsilesional arm reaching movements are not affected by the postural configuration adopted by individuals with stroke. The central nervous system modulates the reaching movements according to the target position, adopted posture, and the uncertainty in the final target position to be reached.

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BACKGROUND: The speculation that apraxia of speech (AOS) is not a unitary diagnosis, but consists of different subtypes instead, has been around for decades. However, attempts to empirically substantiate such a notion remain few and far between. AIMS: The primary objective of this article is to consider the different bases for identifying subtypes of AOS, review existing evidence regarding subtypes under each classification basis, and provide discussion and implications for future research. MAIN CONTRIBUTION: AOS subtypes have been proposed on the basis of clinical symptomatology, theoretical constructs, and an analogy to limb apraxia. Different possible subtypes of AOS are reviewed, along with their empirical support and limitations. Empirical evidence, particularly in the context of a progressive disease, supports the idea that AOS diagnosis may capture different underlying impairments of speech motor planning. Future research to advance our understanding of AOS should carefully consider the basis for subtype classification, and include large sample sizes to differentiate individual variability from possible subtypes. CONCLUSIONS: Several proposed AOS subtypes have found some support in the literature. Further research is needed to determine the validity, coherence and utility of possible AOS subtypes for theoretical and clinical purposes.

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ABSTRACT This study aimed to make a systematic review of scientific articles on the planning of manual motor actions of typical and atypical children. To do so, a search of articles published between 1996 and 2017 was done on PubMed, LILACS, Science Direct, and SciElo databases. Original articles in English and Portuguese evaluating the planning of motor actions in typical and atypical children performing manual tasks were selected. For the analysis, the population age, number of children, type of task, main results, site of study and impact of the journal were considered. From the eighteen articles found, twelve were about typical children (from nine months old to twenty years old) and six about atypical children (from three to fourteen years old) diagnosed with autism, hemiplegic cerebral palsy, and developmental coordination disorders. In nine- to ten-year-old typical children, the planning ability of manual motor actions develops over the time and is similar to that of an adult. The atypical children showed motor planning ability lower than that of the typical children, and determining the age when this planning ability is acquired was not possible.

RESUMO O objetivo desse estudo foi realizar uma revisão sistemática de artigos científicos sobre o planejamento de ações motoras manuais de crianças típicas e atípicas. Para isso, foi feita uma busca de artigos publicados entre 1996 e 2017 nas bases de dados PubMed, Lilacs, Science Direct e SciELO. Foram incluídos artigos originais em língua inglesa e portuguesa, que avaliaram o planejamento de ações motoras em crianças típicas e atípicas por meio de tarefas manuais. Para a análise dos artigos, considerou-se a população, a faixa etária, o número de crianças, o tipo de tarefa, os principais resultados, o local de realização do estudo e o fator de impacto da revista. Ao todo, foram encontrados 18 artigos, sendo 12 com crianças típicas (9 meses a 20 anos de idade), e 6 com crianças atípicas (3 a 14 anos) diagnosticadas com autismo, paralisia cerebral hemiplégica e transtornos de déficit de coordenação. Nas crianças típicas, observa-se que a capacidade de planejamento de ações motoras manuais se desenvolve ao longo do tempo e se assemelha a de um adulto entre os 9 e 10 anos de idade. As crianças atípicas apresentaram capacidade de planejamento motor inferior à das crianças típicas e não foi possível determinar a idade em que essa habilidade de planejamento é estabelecida.

RESUMEN El objetivo de este estudio fue realizar una revisión sistemática de artículos científicos sobre la planificación de acciones motoras manuales de niños típicos y atípicos. Para ello, se realizó una búsqueda de artículos publicados entre 1996 y 2017 en las bases de datos PubMed, Lilacs, Science Direct y SciELO. Se incluyeron artículos originales en inglés y portugués que evaluaron la planificación de acciones motoras en niños típicos y atípicos a través de tareas manuales. Para el análisis de los artículos, se consideró la población, el grupo de edad, el número de niños, el tipo de tarea, los principales resultados, el lugar de realización del estudio y el factor de impacto de la revista. En total, se encontraron 18 artículos, 12 con niños típicos (9 meses a 20 años) y 6 con niños atípicos (3 a 14 años) diagnosticados con autismo, parálisis cerebral hemipléjica y trastornos de déficit de coordinación. En los niños típicos, se observa que la capacidad de planificación de acciones motoras manuales se desarrolla a lo largo del tiempo y entre los 9 y 10 años se asemeja a la de un adulto. Los niños atípicos presentaron una capacidad de planificación de motores inferior a la de los niños típicos y no fue posible determinar la edad en que se estableció esta capacidad de planificación.

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People commonly use pre-cue information to advance and reduce the information processing time required for a motor task (e.g., motor planning). However, children with developmental coordination disorder (DCD) exhibit difficulties performing pre-cued goal-directed tasks. The purpose of the present study was to investigate the use of valid, neutral, and invalid pre-cue information for a goal-directed task. The participants were 11 children with DCD (mean age = 7.94 yrs.) and 11 typically developed (TD) age- and gender-matched children. The children with DCD exhibited delayed motor planning (e.g., reaction time) under the invalid condition compared to that of the TD children. The children with DCD used atypical strategies for motor execution and depended more on online corrections (e.g., increased deceleration time and movement units) to reach the target. These results suggest that children with DCD have difficulties handling unpredictable situations and that the use of atypical motor execution strategies did not affect movement time

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La utilización de observaciones que proporcionan información acerca del funcionamiento sensorio-motor relacionado a procesamiento sensorial es común en la práctica clínica. Un grupo de observaciones, llamadas observaciones clínicas por A.J. Ayres ayuda a diagnosticar disfunciones sensoriales aunque no existen normas desarrolladas en Chile, ni su validez o confiabilidad establecida estadísticamente para su utilización. Para normar estas pruebas en Chile se entrenaron 4 evaluadores quienes recolectaron datos de niños entre 5 y 7.11 años de edad: 90 típicos y 26 identificados con problemas de procesamiento sensorial. Este estudio proporciona datos preliminares sobre 5 pruebas relacionadas a control postural y planeamiento motor: equilibrio en un pie (ojos cerrados y ojos abiertos), extensión antigravitatoria, flexion antigravitatoria, secuenciación de dígitos, y diadochokinesis. Los resultados indican que estas pruebas se pueden utilizar para diagnosticar niños con disfunciones sensorio-motoras en la práctica clínica e investigación.

Clinical observations that provide information about sensory-motor performance related to sensory processing, are commonly used in clinical practice. A group of these observations, known as clinical observations by A. J. Ayres,help diagnose sensory related dysfunctions even when normative data and statistically established validity and reliability are not available for the Chilean children. In order to develop normative data, we trained 4 independent assessors who collected data on 90 typically developing children 5 to 7.11 years of age and 26 children identified as presenting with sensory processing problems. The present study provides preliminary data about 5 observations that relate to postural control and motor planning: Standing on one foot (eyes open and closed), extensión against gravity, flexion against gravity, sequential finger touching and diadochokinesis. The results of this study indicate that these observations can help diagnose children with sensory-motor dysfunctions and be utilized for clinical applications and research.

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It is assumed that social bonds in humans have consequences for virtually all aspects of behavior. Social touch-based contact, particularly hand caressing, plays an important role in social bonding. Pre-programmed neural circuits likely support actions (or predispositions to act) toward caressing contacts. We searched for pre-set motor substrates toward caressing by exposing volunteers to bonding cues and having them gently stroke a very soft cloth, a caress-like movement. The bonding cues were pictures with interacting dyads and the control pictures presented non-interacting dyads. We focused on the readiness potential, an electroencephalographic marker of motor preparation that precedes movement execution. The amplitude of the readiness potential preceding the grasping of pleasant emotional-laden stimuli was previously shown to be reduced compared with neutral ones. Fingers flexor electromyography measured action output. The rationale here is that stroking the soft cloth when previously exposed to bonding cues, a compatible context, would result in smaller amplitudes of readiness potentials, as compared to the context with no such cues. Exposure to the bonding pictures increased subjective feelings of sociability and decreased feelings of isolation. Participants who more frequently engage in mutual caress/groom a "significant other" in daily life initiated the motor preparation earlier, reinforcing the caress-like nature of the task. As hypothesized, readiness potentials preceding the caressing of the soft cloth were significantly reduced under exposure to bonding as compared to control pictures. Furthermore, an increased fingers flexor electromyographic activity was identified under exposure to the former as compared to the latter pictures. The facilitatory effects are likely due to the recruitment of pre-set cortical motor repertoires related to caress-like movements, emphasizing the distinctiveness of neural signatures for caress-like movements.

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The present study aimed to verify the relationship between working memory (WM) and apraxia of speech and explored which WM components were involved in the motor planning of speech. A total of 22 patients and 22 healthy adults were studied. These patients were selected according to the following inclusion criteria: a single brain lesion in the left hemisphere, presence of apraxia of speech and sufficient oral comprehension. This study involved assessment of apraxia of speech and evaluation of working memory capacity. The performance of apraxic patients was significantly poorer than that of controls, where this reached statistical significance. The study concluded that participants with apraxia of speech presented a working memory deficit and that this was probably related to the articulatory process of the phonoarticulatory loop. Furthermore, all apraxic patients presented a compromise in working memory.

O objetivo do presente estudo foi verificar a interrelação entre memória operacional e apraxia verbal e explorar quais os componentes desta memória estariam envolvidos na programação motora da fala. Foram avaliados 22 pacientes apráxicos e 22 controles. Todos os participantes foram submetidos a avaliação da apraxia de fala. Para investigar a memória operacional, foram aplicados o teste de span de dígitos na ordem direta e inversa, um teste de repetição de palavras longas e curtas e o Rey Auditory Verbal Learning Test, que investiga, além da alça articulatória, o buffer episódico. O desempenho dos apráxicos em todos os testes de memória foi estatisticamente significante mais baixo que o desempenho dos controles. Concluímos que indivíduos com apraxia apresentam um déficit na memória operacional e que este déficit está mais relacionado ao processo articulatório da alça fonoarticulatória.

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