<p><strong>Short answer</strong><br>
The retinal image cannot be refocused on an intermediate target during a saccade. </p>

<p><strong>Background</strong><br>
Psychophysical experiments have shown that during a saccade, attention is aimed at the target location. Instructing the subject to make a saccade from location A to C, while focusing on another point B proved impossible. </p>

<p>The authors conclude that: </p>

<blockquote>
  <p>[A] saccade executed to a peripheral location in the visual field
  involves the orienting of attention to that location, prior to the
  actual execution of the saccade. The inability to orient attention to
  one location and simultaneously execute a saccade to another location
  suggests that orienting of attention may be an essential component of
  preparing and/or executing saccades.</p>
</blockquote>

<p>In other words, a saccade is meant to shift the point of focus, and attention cannot be paid to another point during a saccade.</p>

<p><sub><strong>Reference</strong><br>
<strong>-</strong> <a href="http://link.springer.com/article/10.3758/BF03206794#page-1" rel="nofollow noreferrer">Hoffman &amp; Baskaran, <em>Perception &amp; Psychophysics</em> (1995); <strong>57</strong>(6), 787-95</a></sub></p>

CC BY-SA 3.0
2016-06-01T20:03:19.907Z
Well, I can clearly think about things in my peripheral vision while moving my eye about in a different region. I am probably too ignorant of the proper terms.
Emil
CC BY-SA 3.0
2016-06-01T20:07:47.023Z
@Emil - with focus I mean visual focus. Of course you can *think* about something else
AliceD
CC BY-SA 4.0
2016-06-01T10:54:41.883Z
2018-07-07T05:58:43.207Z
2018-07-07T05:58:43.207Z
AliceD
<p>Because of perisaccadic space compression effect, the focus lies inbetween from the saccade onset position to its future offset (target position), but only given the target is inside this region.<br />
In case the target changes its position during saccade; or was not inside it from the start (antisaccade task), there is no compression effect and, therefore, no objects are focused.</p>

CC BY-SA 4.0
2020-10-08T20:03:37.160Z
Welcome. Can you add sources to your material? That way people can background read on your material.
AliceD
CC BY-SA 4.0
2020-10-08T15:04:27.980Z
2020-10-08T15:04:27.980Z
ivan866
<p>Has anyone succeeded in measuring where the focus is between saccades? Through some kind of nonintrusive brainscan perhaps? I would like to be able to draw with my thought :) (Something similar would be okay, like the position or shape I am thinking of overlayed on what I see)</p>

CC BY-SA 3.0
2016-03-16T21:16:42.357Z
The definition of saccades implies that there is no focus between movements. Are you asking if it is possible to track eye movements during a saccade?
Seanny123
CC BY-SA 3.0
2016-03-17T06:46:41.307Z
No, I mean the spot it feels like I am looking at. To me it feels like I move my focus as a smooth curve. I think this could be measured with some kind of brainscan and clever machine learning (the human could draw the ground truth of how it felt it moved its eyes). I do not know if there is a term for this. Percieved focus perhaps?
Emil
CC BY-SA 3.0
2016-03-17T13:37:46.030Z
as @Seanny123 indicates, this question does not make sense. While you may "feel" that you move your "focus" as a smooth curve, this does not reflect the reality of (most) eye movements which are not smooth but jerky saccades. If by "focus" you mean the point at which people are looking and taking in information then this point changes too rapidly during saccades and information processing is suppressed. If you mean the fixations in between saccades (where the eye is mostly still), then yes we can measure them.
splint
CC BY-SA 3.0
2016-03-17T13:38:15.110Z
If you mean "covert" attention, then there are some studies showing brain correlates of this, although the resolution is likely to be very poor.
splint
CC BY-SA 3.0
2016-03-17T23:02:03.237Z
The description on wikipedia of covert attention seems similar to what I mean. Did they measure the brain in realtime using nonintrusive methods? If it can be done at home it would be a pretty awesome toy.
Emil
<neuroscience><vision><eye-movement>
Is there visual focus during a saccade?
Emil
# Is there visual focus during a saccade?

(Asked by: username_0 on 2016-03-16)

Has anyone succeeded in measuring where the focus is between saccades? Through some kind of nonintrusive brainscan perhaps? I would like to be able to draw with my thought :) (Something similar would be okay, like the position or shape I am thinking of overlayed on what I see)

**Tags:** neuroscience, vision, eye-movement

> **Comments:**
> **username_1**: The definition of saccades implies that there is no focus between movements. Are you asking if it is possible to track eye movements during a saccade?  
> **username_0**: No, I mean the spot it feels like I am looking at. To me it feels like I move my focus as a smooth curve. I think this could be measured with some kind of brainscan and clever machine learning (the human could draw the ground truth of how it felt it moved its eyes). I do not know if there is a term for this. Percieved focus perhaps?  
> **username_2**: as @username_1 indicates, this question does not make sense. While you may "feel" that you move your "focus" as a smooth curve, this does not reflect the reality of (most) eye movements which are not smooth but jerky saccades. If by "focus" you mean the point at which people are looking and taking in information then this point changes too rapidly during saccades and information processing is suppressed. If you mean the fixations in between saccades (where the eye is mostly still), then yes we can measure them.  
> **username_2**: If you mean "covert" attention, then there are some studies showing brain correlates of this, although the resolution is likely to be very poor.  
> **username_0**: The description on wikipedia of covert attention seems similar to what I mean. Did they measure the brain in realtime using nonintrusive methods? If it can be done at home it would be a pretty awesome toy.  

---

## 2 answers

### Answer by username_3 on 2016-06-01. Score: 2

**Short answer**  
The retinal image cannot be refocused on an intermediate target during a saccade.

**Background**  
Psychophysical experiments have shown that during a saccade, attention is aimed at the target location. Instructing the subject to make a saccade from location A to C, while focusing on another point B proved impossible.

The authors conclude that:

> [A] saccade executed to a peripheral location in the visual field
> involves the orienting of attention to that location, prior to the
> actual execution of the saccade. The inability to orient attention to
> one location and simultaneously execute a saccade to another location
> suggests that orienting of attention may be an essential component of
> preparing and/or executing saccades.

In other words, a saccade is meant to shift the point of focus, and attention cannot be paid to another point during a saccade.

**Reference**  
**-** [Hoffman & Baskaran, *Perception & Psychophysics* (1995); **57**(6), 787-95](http://link.springer.com/article/10.3758/BF03206794#page-1)

> **Comments:**
> **username_0**: Well, I can clearly think about things in my peripheral vision while moving my eye about in a different region. I am probably too ignorant of the proper terms.  
> **username_3**: @username_0 - with focus I mean visual focus. Of course you can *think* about something else  

---

### Answer by username_4 on 2020-10-08. Score: 0

Because of perisaccadic space compression effect, the focus lies inbetween from the saccade onset position to its future offset (target position), but only given the target is inside this region.  
In case the target changes its position during saccade; or was not inside it from the start (antisaccade task), there is no compression effect and, therefore, no objects are focused.

> **Comments:**
> **username_3**: Welcome. Can you add sources to your material? That way people can background read on your material.  

---

