Research Interests


  Professor Hsieh’s research fields include below topics.

 

  Professor Hsieh’s researches cover different experiment approaches.

Such as…

 

  Research topics:

I. The mechanism of attentional shifting of executive function.

 
Over the past five years, to understand the control theory of attention, Professor Hsieh has systematically manipulated the mechanism of attentional shifting and sorted out several variables that may affect the loss of job conversion.

 Based on the electrophysiological data, we found that two brain component waves, CNV and P300, are correlated with two cognitive function, preparation and interference. Recent research also reports conversion-related brain component wave, P300, is related to the suppression process in the task conflict as well. In addition, Professor Hsieh has successfully used lateralized readiness potentials (LRP) in series studies to identify different conversion task models. Furthermore, the research which our lab is in progress manipulats various variables one by one, to measure whether different types of task conversion involve multiple control mechanisms or not, and to clarify the task conversion process by electrophysiology technology. We are also interested in whether every attentional shifting can be prepared in advance, or only in certain types of conversion task. Related study results are published in succession. (See STUDY button below)

 
After cooperation with Israel Scholars, we discovered a brand-new suppression process. This suppression process is an original selective attention phenomenon, which was just published in the Journal of Experimental Psychology: Learning, Memory and Cognition, the phenomenon is named "Competitor Rule Suppression (CRS)". The CRS phenomenon is that when subjects encounter absolute switching task, to effectively improve the preparation of each task switching, they would start up a highly elaborative operation mechanism.That is, if a certain task dimension in one trial is interfered by the reaction, it would be suppressed immediately. So, if the suppressed task dimension becomes the current target after the task conversion, that would be an extra time required for the anti-suppression process in RTs. This inhibitory mechanism is different from the long-term inhibitory function found in the previous study, and the activity area of brain is also different. At present, the component wave has also been found (Accepts by Cognitive, Affective, and Behavioral Neuroscience). The recent paper try to examines whether CRS fades over time passively or whether is involved in the memory re- retrieval and memory elimination.

 

II. The source of function loss from multiple task

When subjects execute two tasks continuously, which factor would affect the psychological refractory period is also the issue in our lab in the past few years.

Psychological refractory period effect comes from Telford (1931). He found that when the subjects are asked to react two tasks continuously, the response to two tasks would be different. When time interval between two tasks is too short, subjects’ response to second task will be slower. But to the first task, they have no difference in different length of time.

Pashler (1994a) proposed a “response-selection bottleneck model” to this phenomenon. However, recent researches tend to argue that psychological refractory period is not caused by a single bottleneck, but the central stage of some second task can be processed with the first task in parallel. Therefore, Professor Hsieh's research focuses on clarifying whether psychological refractory period is a single bottleneck or partial bottleneck. At present, a paper has been published in Psychonomic Bulletin and Review, which is an important journal in the cognitive psychology.


III. Sleep deprivation and error monitoring

In recent years, to study the relationship between sleep and cognition, Professor Hsieh also cooperates with the Professor Tsai’s Sleep Laboratory in National Chung Cheng University. The results of the study show that sleep deprivation would affect the amplitudes of ERN and Pe, and would tend to make mistakes after mistakes. This study is the first one to propose and confirm that sleep deprivation all night would make the mechanism of avoid making mistakes after mistakes invalid. That is, the influence of sleep deprivation will not only increase the probability of making mistakes, but even increase the probability of mistakes occur after mistakes. Result also suggests that when people in an accident and under sleep deprivation, the chance to remedy mistakes is lower than in a general awake state. In other words, the severity of the accident may be higher.

One of the representative studies encourages subjects to correct their behaviors immediately after mistakes, to observe whether the corrective function would be affected by sleep deprivation or not. The results of the study observed that sleep deprivation will comprehensively improve behavioral performance, including RT, neglect rate, error rate and immediate correction rate. The other important study is to manipulate rewards and punishments in order to observe the changes in the error monitoring system after sleep deprivation. The results of the study found that the effects of external reward factors and internal active correction are different. In recent years, Professor Hsieh has also been invited by international scholars to write a chapter “Sleep deprivation and error negativity” in a special book published by Taylor & Francis Group in 2012.

 

IV. Electrophysiological study of attention control in aging brain

A. Aging in Attentional Blink

“Attentional blink” is, after correct identification of the first target, the wrong identification of second target which appear within 500 milliseconds would happen. Professor Hsieh use some instant attention paradigms to test whether encounter ventral task (number recognition) and dorsal task (click on the target) at the same time can surmount such limitation of the attention. And we also test the difference between elder and young. The result of the study shows that young people would not be disturbed by identification tasks when they are clicking static or moving objects. The result is in line with “dual system theory” proposed by Milner and Goodale (1995). 

The result also suggests the elder would be disturbed by identification tasks when the dual task’s target distance is 100 milliseconds. At this condition, old people need more time to complete the click, that is, the elder would be disturbed more severely. But when the target distance is 700 milliseconds, the difference between single task and dual task disappears gradually.

The behavior results of clicking disappear target show, both the elder and the young are affected by digital recognition when target distance is 100 milliseconds. This result is also consistent with the idea that the ventral system is responsible for objects of ​​grasping memory.

B. Aging and Task Switching

Professor Hsieh's lab also confirmed that aging has a specific rather than comprehensive effect on task switching. This study uses the "same-difference judgment “paradigm to examine the effect of aging on task switching. In this study, we manipulated two dimensions, perception and conceptual, when subjects made same or different judgments, and we also manipulated time interval of "cue-target" to check whether aging would affect the preparation process of task conversion. The results show that although the elder have a large conversion loss, their preparation for conversion has not been flawed, or even have more benefits than young people. 

In addition, the biggest innovation of we used the MMLM developed by Yantis et al. (1991), and this research also based on the formula proposed by de Jong ’s (2000). We used this formula to test what causes the conversion loss of the elder? Is it because the elder have difficulty in preparing for switching jobs to increase gradually? Or is it because of other external factors which operate preparation progress? 

We found that there are difference causes of vary conversion loss value when elder are doing difference judgement task. In the perception judgment, the elder have smaller ratio of absolutely prepare in advance than young people; In the conceptual judgment, the elder are obviously limited to the external waiting factors which induce preparation progress. The phenomenon of aging showing double dissociation in different types of conversion loss mechanisms is an innovative discovery in this study.

C. Aging and inhibitory function

Professor Hsieh recently found that there are significant differences in response of brain waves between old people and young people, although the performance of the elder is not necessarily worse than young people. The results have been accepted for publication in Clinical Neurophysiology.

The diversity of inhibitory functions and when the elder operate the compensatory responses simultaneously didn’t be discussed widely. So, Professor Hsieh systematically manipulated various types of inhibitory task models and the degree of task difficulty, and used the ERP technique at the same time, to gain an in-depth understanding of the aging inhibition function and the compensation mechanism. The results have been published in Biological Psychology.

 

V. Emotional Standard Stimulus and Response Norms: Emotional Films

This project intends to establish a database including various standard stimuli which arouses emotions and the norm of Chinese people's response to these stimuli.

We have three goals:

1. Build a database of standard stimuli which arouses emotions, and focus on eight dimensions such as facial expressions, pictures, words, metaphors, jokes, tones, short films, and music.

2. Based on above standard stimulus database, we establish normative data of Chinese people's emotional responses, including cognitive assessment, muscle response (eye movement), and peripheral autonomic response (heartbeat, blood pressure, breath and skin electrical response, etc.).

3. Explore the brain activity (EEG and ERP) of Chinese people to different emotional stimuli.

Whether the specific emotion has a specific autonomic nervous system (ANS) response has always been a topic of psychologists. The “emotional process theory” proposed by James (1884), pointed out that emotions have different patterns of autonomic nervous response. Although some scholars have already proved that there are empirical data show that some emotions can be distinguished in different autonomic nervous response pattern, there is still no specific integration result of the ANS response and emotion.

Our lab research projects use Ekman's (1984) basic emotion as independent variables to select stimulus materials, and use two-dimensional variable theory and autonomic neural response mode as dependent variables. We also do some quantitative analysis of emotional short film data. The study has been published in the Chinese Journal of Psychology.

 

VI. Neuropsychology

Our research issues including:

1. Cognitive and attentional function changes in patients with brain injury.

2. Discussion on the attention conversion function of basal nucleus and frontal striatum circuit.

3. Compilation of neuropsychological test and establishment of norms, etc.

Professor Hsieh's research in neuropsychology is mainly focused on the attention function of patients with Parkinson's disease. The motivation for this type of research is that the frontal lobe is mainly responsible for performing control functions, and there is an inseparable neural circuit connection between the basal nucleus and the frontal lobes. It is important to understand the role of the basal nucleus in cognitive function. However, most researchers have only observed that patients with impaired frontal lobe and patients with Parkinson's disease exhibit similar cognitive defects, but in fact the internal causes of their cognitive defects are likely to be different.

Through empirical research, Professor Hsieh found that attention deficits in patients with Parkinson's disease are specific, and only in the reverse conversion of the consistent stimulus-response connection. This result is likely to be the basis of future research to distinguish the difference between cognitive functions of frontal lobe and cognitive functions of basal nucleus.In addition, Professor Hsieh also discussed the attentional function of frontal epilepsy and found the function defect is different from that of patients with Parkinson's disease. This also shows that the frontal lobe and basal nucleus may play different roles in attention function.

In the children's cognitive function study, children with learning disabilities are unlike other special children have clear causes and diagnostic criteria. So, there is an urgent need to develop test tools to help understand the specific cognitive defects of these children, which hinder effective learning. This early project that Professor Hsieh participated in has had concrete results such as reliability and norms, and has been used in clinical.

 

VII. Clinical Psychology

In the field of clinical psychology, Professor Hsieh has directed master students of the Institute of Behavioral Medicine to conduct the following three studies: (1) & (2) have been published in the Chinese Journal of Mental Health.

(1) Discussion on Selective Attention in College Students with Obsessive-Compulsive Symptoms Facilities

The goal of the present study was to explore the function of selective attention in people with obsessive-compulsion symptoms. The visuospatial priming paradigm with non-verbal stimulus, e.g., location, was employed in this study. The paradigm was designed to examine the ability of facilitating the relevant information and/or inhibiting the irrelevant information. All participants completed the Health Personality Habits Inventory, and Maudsley Obsessional-Compulsive Inventory, and they were classified into three groups, non-anxious control group, general-anxious control group, and obsessional-compulsive group based on the screening score reflected on the two Inventories. They further performed the visuospatial priming paradigm. The result showed that the inhibition effect is significantly smaller in the obsessional-compulsive group than the other two groups. Contrary to the previous finding of no diminished inhibition, our results show that people with obsessive-compulsion symptoms suffered from inhibition deficit on the location-based priming task.

(2) Attention Inhibition and Memory Retrieval toward Emotional Faces on Patients of Obsessive-Compulsive Disorder and Other Anxiety Disorders: Using Negative Priming Paradigm

In this study we tried to confirm the defect inhibition hypothesis and assumed a vanished negative priming effect in anxious individuals. We also tried to see if there was a different threat-related negative priming that may differentiate between the inhibition and the retrieval process in these anxious individuals.

Study subjects included twenty two medication-free patients of obsessive-compulsive disorder (OCD) and twenty one medication-free patients of other anxiety disorders (OAD), as well as thirty matched healthy subjects without any psychiatric history. Each subject's anxiety level was evaluated by the use of the State-Trait Anxiety Inventory. The Flanker paradigm of the negative priming task was used. ANOVA reaction time analysis show that normal people have negative and threatening priming effects. Other patients with anxiety disorder do not have neutral negative priming effects, but they have negative threatening priming effects. However, the negative priming effects of patients with obsessive-compulsive disorder disappeared.The results of the study prove the hypothesis of suppressing defects and imply a possible cognitive avoidance effect. Patients with obsessive-compulsive disorder and other anxiety disorders have significantly different types of performance, suggesting that they have different pathological mechanisms. In the discussion, the possible effects of attention suppression and memory extraction are included, and try to explain relevant clinical performance of the patients.

(3) Selective Processing of Positive and Negative Information inClinical Depression: The Bias of Activation and Inhibition.

The present study was designed to examine selective attentional functioning in clinical depressive participants. Experimental variables were repetition (repeating and non-repeating) and stimulus valence (neutral, positive and negative contents). The participants included 22 major depressive patients and 30 matched healthy participants. A negative priming task included prime and probe pairs. The repeated condition differed from the non-repeated one in that the probe display target was the same words as the prime display distractor. Color cue, distractor and target were simultaneously presented for 500 msec, and then the participants quickly pressed an assigned key. The recorded key-press time was analyzed by the nonparametric statistical method. Results showed that depressive patients failed to exhibit negative priming at all conditions, and that healthy subjects revealed negative priming only at the neutral condition. Compared to the healthy subjects, the depressive patients are not capable of inhibiting neutral distractors. The findings can be explained by the attention inhibition and memory retrieval hypotheses, which suggest depressive patients disrupt attention inhibition and memory retrieval function and that processing differences in neutral distractors exist between the healthy participants and depressive patients.



   

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