Nicolas Carvalho | University of Lausanne (original) (raw)

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Research paper thumbnail of Eye Movement in Unipolar and Bipolar Depression: A Systematic Review of the Literature

Frontiers in psychology, 2015

The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to in... more The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to investigate mood regulation, emotional information processing, and psychomotor disturbances in depressive disorders. A systematic review of all English language PubMed articles using the terms "saccadic eye movements" OR "eye-tracking" AND "depression" OR "bipolar disorders" was conducted using PRISMA guidelines. The aim of this review was to characterize the specific alterations of EM in unipolar and bipolar depression. Findings regarding psychomotor disturbance showed an increase in reaction time in prosaccade and antisaccade tasks in both unipolar and bipolar disorders. In both disorders, patients have been reported to have an attraction for negative emotions, especially for negative pictures in unipolar and threatening images in bipolar disorder. However, the pattern could change with aging, elderly unipolar patients disengaging key features of s...

Research paper thumbnail of Motor Imagery in Unipolar Major Depression

Frontiers in Behavioral Neuroscience, 2014

Motor imagery is a potential tool to investigate action representation, as it can provide insight... more Motor imagery is a potential tool to investigate action representation, as it can provide insights into the processes of action planning and preparation. Recent studies suggest that depressed patients present specific impairment in mental rotation. The present study was designed to investigate the influence of unipolar depression on motor imagery ability. Fourteen right-handed patients meeting DSM-IV criteria for unipolar depression were compared to 14 matched healthy controls. Imagery ability was accessed by the timing correspondence between executed and imagined movements during a pointing task, involving strong spatiotemporal constraints (speed/accuracy trade-off paradigm). Compared to controls, depressed patients showed marked motor slowing on both actual and imagined movements. Furthermore, we observed greater temporal discrepancies between actual and mental movements in depressed patients than in healthy controls. Lastly, depressed patients modulated, to some extent, mental movement durations according to the difficulty of the task, but this modulation was not as strong as that of healthy subjects. These results suggest that unipolar depression significantly affects the higher stages of action planning and point out a selective decline of motor prediction.

Research paper thumbnail of 2182 – Inhibition in elderly depressed patients: An eye tracking study

European Psychiatry, 2013

ABSTRACT Background Depression in people aged 65 and more appears to be a major public health pro... more ABSTRACT Background Depression in people aged 65 and more appears to be a major public health problem. Efficient mechanisms of inhibition are important to communicate with other people and to interact with the environment but seem to be deficient in young depressed patients. This function needs to be evaluated in late life depression which has specific features. Method Twenty inpatients (mean age = 70.4) meeting DSM-IV criteria for major depressive disorder were compared to forty seven healthy controls. They performed a neuropsychological and psychiatric assessments and two eye movement tasks: a prosaccades task to obtain basic parameters of eye movements and an antisaccade task to evaluate the inhibition capacities. Results In comparison with healthy subjects, depressed patients showed impaired performances in both oculomotor tasks. Concerning the prosaccade trial, depressed patients had higher reaction times and error rates than healthy controls. In both populations, hypometric saccades are the main kind of error. In the antisaccade task, reaction times and error rates were also higher in depressed patients than healthy subjects. However, the two populations showed similar correction rates. Conclusion The results of this study offer new insight on the inhibition impairment of aged major depressive patients by two simple eye movement tasks. The findings indicate psychomotor retardation and inhibition impairment, consistent with the findings obtained in young depressed subjects.

Research paper thumbnail of Visual scanning behavior during processing of emotional faces in older adults with major depression

Aging & Mental Health, 2014

Although several reported studies have suggested that younger adults with depression display depr... more Although several reported studies have suggested that younger adults with depression display depressionrelated biases during the processing of emotional faces, there remains a lack of data concerning these biases in older adults. The aim of our study was to assess scanning behavior during the processing of emotional faces in depressed older adults. Method: Older adults with and without depression viewed happy, neutral or sad portraits during an eye movement recording. Results: Depressed older adults spent less time with fewer fixations on emotional features than healthy older adults, but only for sad and neutral portraits, with no significant difference for happy portraits. Conclusion: These results suggest disengagement from sad and neutral faces in depressed older adults, which is not consistent with standard theoretical proposals on congruence biases in depression. Also, aging and associated emotional regulation change may explain the expression of depression-related biases. Our preliminary results suggest that information processing in depression consists of a more complex phenomenon than merely a general searching for moodcongruent stimuli or general disengagement from all kinds of stimuli. These findings underline that care must be used when evaluating potential variables, such as aging, which interact with depression and selectively influence the choice of relevant stimulus dimensions.

Research paper thumbnail of Saccadic Eye Movements in Depressed Elderly Patients

PLoS ONE, 2014

The primary aim of this study was to characterize oculomotor performances in elderly depressed pa... more The primary aim of this study was to characterize oculomotor performances in elderly depressed patients. The second aim was to investigate whether cognitive inhibition measured by the antisaccade task was associated with a psychomotor retardation or rather with a more specific cognitive-motor inhibition deficit. Twenty patients with a major depressive disorder and forty-seven healthy subjects performed two eye movement tasks. Saccadic reaction time and error rates were analyzed in the prosaccade task to obtain basic parameters of eye movements. Saccade latency, error rates and correction rates were evaluated in the antisaccade task to investigate inhibition capacities. Performances were impaired in patients, who exhibited a higher reaction time and error rates compared to controls. The higher time cost of inhibition suggested that the reaction time was not related to global psychomotor retardation alone. The higher time cost of inhibition could be explained by a specific alteration of inhibition processes evaluated by the antisaccade task. These changes were associated with the severity of depression. These findings provide a new perspective on cognitive inhibition in elderly depressed patients and could have important clinical implications for our understanding of critical behaviors involving deficits in inhibitory processes in the elderly.

Research paper thumbnail of Eye Movement in Unipolar and Bipolar Depression: A Systematic Review of the Literature

Frontiers in psychology, 2015

The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to in... more The analysis of eye movements (EM) by eye-tracking has been carried out for several decades to investigate mood regulation, emotional information processing, and psychomotor disturbances in depressive disorders. A systematic review of all English language PubMed articles using the terms "saccadic eye movements" OR "eye-tracking" AND "depression" OR "bipolar disorders" was conducted using PRISMA guidelines. The aim of this review was to characterize the specific alterations of EM in unipolar and bipolar depression. Findings regarding psychomotor disturbance showed an increase in reaction time in prosaccade and antisaccade tasks in both unipolar and bipolar disorders. In both disorders, patients have been reported to have an attraction for negative emotions, especially for negative pictures in unipolar and threatening images in bipolar disorder. However, the pattern could change with aging, elderly unipolar patients disengaging key features of s...

Research paper thumbnail of Motor Imagery in Unipolar Major Depression

Frontiers in Behavioral Neuroscience, 2014

Motor imagery is a potential tool to investigate action representation, as it can provide insight... more Motor imagery is a potential tool to investigate action representation, as it can provide insights into the processes of action planning and preparation. Recent studies suggest that depressed patients present specific impairment in mental rotation. The present study was designed to investigate the influence of unipolar depression on motor imagery ability. Fourteen right-handed patients meeting DSM-IV criteria for unipolar depression were compared to 14 matched healthy controls. Imagery ability was accessed by the timing correspondence between executed and imagined movements during a pointing task, involving strong spatiotemporal constraints (speed/accuracy trade-off paradigm). Compared to controls, depressed patients showed marked motor slowing on both actual and imagined movements. Furthermore, we observed greater temporal discrepancies between actual and mental movements in depressed patients than in healthy controls. Lastly, depressed patients modulated, to some extent, mental movement durations according to the difficulty of the task, but this modulation was not as strong as that of healthy subjects. These results suggest that unipolar depression significantly affects the higher stages of action planning and point out a selective decline of motor prediction.

Research paper thumbnail of 2182 – Inhibition in elderly depressed patients: An eye tracking study

European Psychiatry, 2013

ABSTRACT Background Depression in people aged 65 and more appears to be a major public health pro... more ABSTRACT Background Depression in people aged 65 and more appears to be a major public health problem. Efficient mechanisms of inhibition are important to communicate with other people and to interact with the environment but seem to be deficient in young depressed patients. This function needs to be evaluated in late life depression which has specific features. Method Twenty inpatients (mean age = 70.4) meeting DSM-IV criteria for major depressive disorder were compared to forty seven healthy controls. They performed a neuropsychological and psychiatric assessments and two eye movement tasks: a prosaccades task to obtain basic parameters of eye movements and an antisaccade task to evaluate the inhibition capacities. Results In comparison with healthy subjects, depressed patients showed impaired performances in both oculomotor tasks. Concerning the prosaccade trial, depressed patients had higher reaction times and error rates than healthy controls. In both populations, hypometric saccades are the main kind of error. In the antisaccade task, reaction times and error rates were also higher in depressed patients than healthy subjects. However, the two populations showed similar correction rates. Conclusion The results of this study offer new insight on the inhibition impairment of aged major depressive patients by two simple eye movement tasks. The findings indicate psychomotor retardation and inhibition impairment, consistent with the findings obtained in young depressed subjects.

Research paper thumbnail of Visual scanning behavior during processing of emotional faces in older adults with major depression

Aging & Mental Health, 2014

Although several reported studies have suggested that younger adults with depression display depr... more Although several reported studies have suggested that younger adults with depression display depressionrelated biases during the processing of emotional faces, there remains a lack of data concerning these biases in older adults. The aim of our study was to assess scanning behavior during the processing of emotional faces in depressed older adults. Method: Older adults with and without depression viewed happy, neutral or sad portraits during an eye movement recording. Results: Depressed older adults spent less time with fewer fixations on emotional features than healthy older adults, but only for sad and neutral portraits, with no significant difference for happy portraits. Conclusion: These results suggest disengagement from sad and neutral faces in depressed older adults, which is not consistent with standard theoretical proposals on congruence biases in depression. Also, aging and associated emotional regulation change may explain the expression of depression-related biases. Our preliminary results suggest that information processing in depression consists of a more complex phenomenon than merely a general searching for moodcongruent stimuli or general disengagement from all kinds of stimuli. These findings underline that care must be used when evaluating potential variables, such as aging, which interact with depression and selectively influence the choice of relevant stimulus dimensions.

Research paper thumbnail of Saccadic Eye Movements in Depressed Elderly Patients

PLoS ONE, 2014

The primary aim of this study was to characterize oculomotor performances in elderly depressed pa... more The primary aim of this study was to characterize oculomotor performances in elderly depressed patients. The second aim was to investigate whether cognitive inhibition measured by the antisaccade task was associated with a psychomotor retardation or rather with a more specific cognitive-motor inhibition deficit. Twenty patients with a major depressive disorder and forty-seven healthy subjects performed two eye movement tasks. Saccadic reaction time and error rates were analyzed in the prosaccade task to obtain basic parameters of eye movements. Saccade latency, error rates and correction rates were evaluated in the antisaccade task to investigate inhibition capacities. Performances were impaired in patients, who exhibited a higher reaction time and error rates compared to controls. The higher time cost of inhibition suggested that the reaction time was not related to global psychomotor retardation alone. The higher time cost of inhibition could be explained by a specific alteration of inhibition processes evaluated by the antisaccade task. These changes were associated with the severity of depression. These findings provide a new perspective on cognitive inhibition in elderly depressed patients and could have important clinical implications for our understanding of critical behaviors involving deficits in inhibitory processes in the elderly.